Chapter 1 Administration

Chapter 2 Definitions

Chapter 3 General Regulations

Chapter 4 Ventilation Air

Chapter 5 Exhaust Systems

Chapter 6 Duct Systems

Chapter 7 Combustion Air

Chapter 8 Chimneys and Vents

Chapter 9 Installation of Specific Appliances

Chapter 10 Boilers and Pressure Vessels

Chapter 11 Refrigeration

Chapter 12 Hydronics

Chapter 13 Fuel Gas Piping

Chapter 14 Process Piping

Chapter 15 Solar Energy Systems

Chapter 16 Stationary Power Plants

Chapter 17 Referenced Standards

Appendices [PDF]

Appendix A Residential Plan Examiner Review Form for HVAC System Design

Appendix B Procedures to be Followed to Place Gas Equipment in Operation

Appendix C Installation and Testing of Oil (Liquid) Fuel-Fired Equipment

Appendix D Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks

Appendix E Sustainable Practices

Appendix F Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design

Appendix G Example Calculation of Outdoor Air Rate

The purpose of this appendix is to provide a comprehensive set of technically sound provisions that encourage sustainable practices and works towards enhancing the design and construction of mechanical systems that result in a positive long-term environmental impact. This appendix is not intended to circumvent the health, safety, and general welfare requirements of this code.
For the purposes of this code, the definitions shall apply to this appendix.

    No attempt is made to define ordinary words, which are used in accordance with their established dictionary meanings, except where a word has been used loosely and it is necessary to define its meaning as used in this appendix to avoid misunderstanding.

    The definitions of terms are arranged alphabetically according to the first word of the term.
Cycles of concentration equals the specific conductance of the water in the cooling tower basin divided by the combined flow weighted average specific conductance of the makeup water(s) to the cooling tower.
A joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. Energy Star is a voluntary program designed to identify and promote energy-efficient products and practices.
Renewable energy generated by deep-earth.
The total heating output of a heat pump during its normal annual usage period for heating in British thermal units (Btu) (kW•h) divided by the total electric energy input during the same period. [ASHRAE 90.1:3.2]
A single-number figure of merit expressing cooling part-load EER efficiency for commercial unitary air-conditioning and heat pump equipment on the basis of weighted operation at various load capacities for the equipment. [ASHRAE 90.1:3.2]
A single number figure of merit based on part-load EER, COp, or kW/ton expressing part-load efficiency for air-conditioning and heat pump equipment on the basis of weighted operation at various load capacities for the equipment. [ASHRAE 90.1:3.2]
The upkeep of property or equipment by the owner of the property in accordance with the requirements of this appendix.
Filter minimum efficiency reporting value, in accordance with ASHRAE 52.2.
Indoor spaces used for presentations and training, including classrooms and conference rooms.
A system of hot water supply and return piping with shutoff valves, balancing valves, circulating pumps, and a method of controlling the circulating system.
The total cooling output of an air conditioner during its normal annual usage period for cooling in Btu (kW•h) divided by the total electric energy input during the same period in Btu (kW•h). [ASHRAE 90.1:3.2]
Mechanical systems covered by this appendix shall be installed in accordance with this code, other applicable codes, and the manufacturer's installation and operating instructions.
Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer or service technician shall be licensed to perform such work.
It shall be unlawful for a person to cause, suffer, or permit the disposal of liquid wastes, in a place or manner, except through and by means of an approved drainage system, installed and maintained in accordance with the provisions of the plumbing code.
Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected to the drainage system of the building or premises in accordance with the requirements of the plumbing code and this appendix.
An abandoned system or part thereof covered under the scope of this appendix shall be disconnected from remaining systems, drained, plugged, and capped in an approved manner.
The provisions of this section establish the means of conserving potable and nonpotable water used in and around a building.
A water meter shall be required for buildings connected to a public water system, including municipally supplied reclaimed (recycled) water. In other than single-family houses, multi-family structures not exceeding three stories above grade, and modular houses, a separate meter or submeter shall be installed in the following locations:
  1. The makeup water supply to cooling towers, evaporative condensers, and fluid coolers.
  2. The makeup water supply to one or more boilers collectively exceeding 1000000 British thermal units per hour (Btu/h) (293 kW).
  3. The water supply to a water-using process where the consumption exceeds 1000 gallons per day (gal/d) (0.0438 L/s), except for manufacturing processes.
  4. The makeup water supply to an evaporative cooler having an air flow exceeding 30000 cubic feet per minute (ft3/min) (14.1584 m3/s).
A means of communicating water consumption data from submeters to the water consumer shall be provided.
Meters and submeters shall be accessible.
Once-through cooling using potable water is prohibited.
Cooling towers and evaporative coolers shall be equipped with makeup water and blow down meters, conductivity controllers, and overflow alarms. Cooling towers shall be equipped with efficiency drift eliminators that achieve drift reduction to 0.002 percent of the circulated water volume for counterflow towers and 0.005 percent for cross-flow towers.
Not less than 5 cycles of concentration is required for air-conditioning cooling tower makeup water having a total hardness of less than 11 grains per gallon (gr/gal) (188 mg/L) expressed as calcium carbonate. Not less than 3.5 cycles of concentration is required for air-conditioning cooling tower makeup water having a total hardness equal to or exceeding 11 gr/gal (188 mg/L) expressed as calcium carbonate.

Exception: Air-conditioning cooling tower makeup water having discharge conductivity range not less than 7 gr/gal (120 mg/L) to 9 gr/gal (154 mg/L) of silica measured as silicon dioxide.
Evaporative cooling systems shall use 3.5 gallons (13.2 L) or less of water per ton-hour (kW•h) of cooling where system controls are set to maximum water use. Water use, expressed in maximum water use per ton-hour (kW•h) of cooling, shall be marked on the device and included in the product user manual, product information literature, and manufacturer's installation instructions. Water use information shall be readily available at the time of code compliance inspection.
Cooling systems shall be equipped with an overflow alarm to alert building owners, tenants, or maintenance personnel where the water refill valve continues to allow water to flow into the reservoir where the reservoir is full. The alarm shall have a sound pressure level rating of not less than 85 dBa measured at a distance of 10 feet (3048 mm).
Cooling systems shall automatically cease pumping water to the evaporation pads where airflow across evaporation pads ceases.
A water quality management system (either timer or water quality sensor) shall be provided. Where timers are used, the time interval between discharge of reservoir water shall be set to 6 or more hours of cooler operation. Where water quality sensors are used, the discharge of reservoir water shall be set for 800 ppm or more of total dissolved solids (TDS). Continuous discharge or continuous bleed systems shall not be installed.
Discharge water shall be reused where applications exist on site. Where a nonpotable water source system exists on site, evaporative cooler discharge water shall be collected and discharged to the collection system.

Exception: Where the reservoir water affects the quality of the nonpotable water supply making the nonpotable water unusable for its intended purposes.
Where discharge water is not recovered for reuse, the sump overflow line shall not be directly connected to a drain. Where the discharge water is discharged into a sanitary drain, an air gap of not less than 6 inches (152 mm) shall be provided between the termination of the discharge line and the drain opening. The discharge line shall terminate in a location that is visible to the building owner, tenants, or maintenance personnel.
Where approved for use by the water or wastewater utility and the Authority Having Jurisdiction, reclaimed (recycled) or on-site treated nonpotable water shall be permitted to be used for industrial and commercial cooling or air-conditioning.
A drift eliminator shall be utilized in a cooling system, utilizing alternate sources of water, where the aerosolized water is capable of coming in contact with employees or members of the public.
A biocide shall be used to treat the cooling system recirculation water where the recycled water is capable of coming in contact with employees or members of the public.
The provisions of this section shall establish the means of enhancing energy efficiency associated with mechanical systems in a building.
The heating, ventilating, air-conditioning, for single-family houses, multi-family structures not exceeding three stories above grade, and modular houses shall be in accordance with Section E 502.2 through Section E 502.12. The heating, ventilation, and air-conditioning system of other buildings shall be in accordance with Section E 503.0.
This section shall regulate only equipment using single-phase electric power, air conditioners, and heat pumps with rated cooling capacities less than 65000 British thermal units per hour (Btu/h) (19 kW), warn1 air furnaces with rated heating capacities less than 225000 Btu/h (66 kW), boilers less than 300000 Btu/h (88 kW) input, and heating-only heat pumps with rated heating capacities less than 65000 Btulh (19 kW). [ASHRAE 90.2:6.2]
Heating, ventilating, and air-conditioning systems and equipment that do not fall under the requirements of Section E 502.0 shall be in accordance with the applicable requirements of Section E 503.0.
The air distribution system design, including outlet grilles, shall provide a means for balancing the air distribution system unless the design procedure provides a system intended to operate within plus or minus 10 percent of design air quantities. [ASHRAE 90.2:6.3]
Balancing dampers shall be installed in branch ducts and the axis of the damper shall be installed parallel to the direction of airflow in the main duct.
Ducts shall be sized, installed, and tested in accordance with Section E 502.4.1 through Section E 502.4.4.
Portions of the air distribution system installed in or on buildings for heating and cooling shall be R-8. Where the mean outdoor dew-point temperature in a month exceeds 60°F (16°C), vapor retarders shall be installed on conditioned-air supply ducts. Vapor retarders shall have a water vapor permeance not exceeding 0.5 perm [2.87 E-11 kg/(Pa•s•m2)] where tested in accordance with Procedure A in ASTM E96.

    Insulation shall not be required where the ducts are within the conditioned space. [ASHRAE 90.2:6.4]
Joints, seams, and penetrations of duct systems shall be made airtight by means of mastics, gasketing, or other means in accordance with this code. Register penetrations shall be sealed to the wall or floor assemblies. Where HVAC duct penetrates a conditioned space, the duct penetration shall be sealed to the wall or floor assembly to prevent leakage into an unconditioned space.
For systems with a duct or air handler outside of the conditioned space, a duct leakage test shall be performed in accordance with Section E 502.4.3.1.
Ductwork shall be tested to the maximum permitted leakage in 1 cubic foot per minute (ft3/min) per 100 square feet [0.0001 (m3/s)/m2] of duct surface area in accordance with SMACNA HVAC Air Duct Leakage Test Manual. Register penetrations shall be sealed during the test. The test shall be conducted with a pressure differential of 0.1 inch water gauge (0.02 kPa) across the tested system.
Duct systems shall be sized in accordance with ACCA Manual D or other methods approved by the Authority Having Jurisdiction with the velocity in the main duct not to exceed 1000 feet per minute (ft/min) (5.08 m/s) and the velocity in the secondary branch duct not to exceed 600 ft/min (3.048 m/s).
HVAC system piping installed to serve buildings and within buildings shall be thermally insulated in accordance with Table E 502.5. [ASHRAE 90.2:6.5]

TABLE E 502.5
MINIMUM PIPE INSULATIONTHICKNESS1,5
[ASHRAE 90.2: TABLE 6.5]
INSULATION CONDUCTIVITY NOMINAL PIPE DIAMETER (inches)
FLUID DESIGN
OPERATING
TEMPERATURE
RANGE (°F)
Btu•inch/(h•ft2•°F) MEAN RATING
TEMPERATURE
(°F)
<1 1 TO 114 112 TO 312 4 TO 6 EQUAL TO
OR GREATER
THAN 8
HEATING SYSTEMS (STEAM, STEAM CONDENSATE, AND HOT WATER)2, 3
201-250 0.27-0.30 150 1.5 1.5 2.0 2.0 2.0
141-200 0.25-0.29 125 1.0 1.0 1.0 1.5 1.5
105- 140 0.22- 0.28 100 0.5 0.5 1.0 1.0 1.0
COOLING SYSTEMS (CHILLED WATER, BRINE, AND REFRIGERANT)4
40-55 0.22- 0.28 100 0.5 0.5 1.0 1.0 1.0
Below 40 0.22- 0.28 100 0.5 1.0 1.0 1.0 1.5
For SI Units: °C= (°F-32)/1.8, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•K)], 1 inch = 25 mm

Notes:
1 For insulation outside the stated conductivity range, the minimum thickness (T) shall be determined as follows:

T = r{(1 + t/r)K/k - 1}

Where:
T = minimum insulation thickness (inches).
r = actual outside radius of pipe (inches) (mm).
t = insulation thickness listed in this table for applicable fluid temperature and pipe size.
K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft2•°F) [W/(m•K)].
k = the upper value of the conductivity range listed in this table for the applicable fluid temperature.

2   These thicknesses are based on energy efficiency considerations only. Additional insulation is sometimes required relative to safety issues/surface temperature.
3   Piping insulation is not required between the control valve and coil on run-outs where the control valve is located within 4 feet (1219 mm) of the coil and the pipe size is 1 inch (25 mm) or less.
4   These thicknesses are based on energy efficiency considerations only. Issues such as water vapor penneability or surface condensation sometimes require vapor retarders, additional insulation or both.
5   For piping exposed to outdoor air, increase insulation thickness by 12 of an inch (12.7 mm). The outdoor air is defined as any portion of insulation that is exposed to outdoor air. For example, attic spaces and crawlspaces are considered exposed to outdoor air.
The building shall be designed to have the capability to provide the ventilation air specified in Table E 502.6. Mechanical ventilation shall be calculated in accordance with Equation E 502.6. [ASHRAE 90.2:6.6.1]

Mechanical Ventilation = [(0.35 - Summer) x Volume] / 60 (Equation E 502.6)

Where:
Mechanical Ventilation = required mechanical ventilation
rate to supplement summer
infiltration, cfm (m3/s)
Summer = summer design infiltration rate, ACH
Volume = volume of conditioned space, ft3 (m3)


TABLE E 502.6
VENTILATION AIR
[ASHRAE 90.2: TABLE 6.6.1]
CATEGORY MINIMUM REQUIREMENT CONDITIONS
Mechanical ventilation1 50 ft3/min outdoor air Where summer design infiltration rate calculated in accordance with
reference standard (a) or (b) is less than 0.35 ACH2.
Kitchen exhaust 100 ft3/min intermittent All conditions
Bath exhaust intermittent All conditions
For SI units: 1 cubic foot per minute = 0.00047 m3/s

Notes:
1   Calculate in accordance with Equation E 502.6.
2   Reference standards:
  1. ACCA Manual J
  2. ASHRAE GRP-158
Combustion air for fossil fuel heating equipment shall comply with this code or with one of the following:
  1. Natural gas and propane heating equipment, NFPA 54
  2. Oil heating equipment, NFPA 31
  3. Solid fuel burning equipment, NFPA 211 [ASHRAE 90.2:6.6.2]
Electric heating systems shall be installed in accordance with the following requirements. [ASHRAE 90.2:6.7]
Where wall, floor, or ceiling electric-resistance heating units are used, the structure shall be zoned and heaters installed in each zone in accordance with the heat loss of that zone. Where living and sleeping zones are separate, the number of zones shall be not less than two. Where two or more heaters are installed in one room, they shall be controlled by one thermostat. [ASHRAE 90.2:6.7.1]
Where electric central warm air heating is to be installed, an electric heat pump or an off-peak electric heating system with thermal storage shall be used.

Exceptions:
  1. Electric resistance furnaces where the ducts are located inside the conditioned space, and not less than two zones are provided where the living and sleeping zones are separate.
  2. Packaged air-conditioning units with supplemental electric heat. [ASHRAE 90.2:6.7.2]
Bath ceiling units providing a combination of heat, light, or ventilation shall be provided with controls permitting separate operation of the heating function. [ASHRAE 90.2:6.8]
HVAC system equipment and system components shall be furnished with the input(s), the output(s), and the value of the appropriate performance descriptor of HVAC products in accordance with federal law or in accordance with Table E 502.9, as applicable. These shall be based on newly produced equipment or components. Manufacturer's instructions shall be furnished with and attached to the equipment. The manufacturer of electric-resistance heating equipment shall furnish full-load energy input over the range of voltages at which the equipment is intended to operate. [ASHRAE 90.2:6.9]

TABLE E 502.9
MINIMUM REQUiREMENTS FOR NON-FEDERALLY COVERED HVAC EQUIPMENT
[ASHRAE 90.2: TABLE 6.9]
EQUIPMENT TYPE SUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCY TEST PROCEDURE
Groundwater source heat pump* Cooling Mode 11.0 EER at 70°F Ent. Water ARI 325
11.5 EER at 50°F Ent. Water
Heating Mode 3.4 COP at 70°F Ent. Water
3.0 COP at 50°F Ent. Water
Unitary A/C Water cooled split system 9.3 EER at 85°F Ent. Water ARI 210/240
8.3 IPLV at 75°F Ent. Water
Evaporatively cooled split system 9.3 EER at 95°F Out. Amb.
8.5 IPLV at 80°F Out. Amb.
For SI units: °C = (°F-32)/1.8
*  Performance for electrically powered equipment with capacity less than 65000 Btu/h (19 kW) where rated in accordance with ARI 325.
Each system or each zone within a system shall be provided with not less than one thermostat capable of being set from 55°F (13°C) to 85°F (29°C) and capable of operating the system's heating and cooling. The thermostat or control system, or both, shall have an adjustable deadband, the range of which includes a setting of 10°F (6°C) between heating and cooling where automatic changeover is provided. Wall-mounted temperature controls shall be mounted on an inside wall. [ASHRAE 90.2:6.10.1]
The control shall initially be set for a maximum heating temperature of 70°F (21°C) and a cooling temperature of not less than 78°F (26°C).
Each mechanical ventilation system (supply, exhaust, or both) shall be equipped with a readily accessible switch or other means for shutoff. Manual or automatic dampers installed for the purpose of isolating outside air intakes and exhausts from the air distribution system shall be designed for tight shutoff. [ASHRAE 90.2:6.10.2]
Where additional energy-consuming equipment is provided for adding moisture to maintain specific selected relative humidities in spaces or zones, a humidistat shall be provided. This device shall be capable of being set to prevent energy from being used to produce relative humidity within the space above 30 percent. [ASHRAE 90.2:6.10.3.1]
Where additional energy-consuming equipment is provided for reducing humidity, it shall be equipped with controls capable of being set to prevent energy from being used to produce a relative humidity within the space below 50 percent during periods of human occupancy and below 60 percent during unoccupied periods. [ASHRAE 90.2:6.10.3.2]
Freeze protection systems, such as heat tracing of outdoor piping and heat exchangers, including self-regulating heat tracing, shall include automatic controls capable of shutting off the systems where outdoor air temperatures are above 40°F (4°C) or where the conditions of the protected fluid will prevent freezing. Snow- and ice-melting systems shall include automatic controls capable of shutting off the systems where the pavement temperature is above 50°F (10°C) and no precipitation is falling and an automatic or manual control that will allow shutoff where the outdoor temperature is above 40°F (4°C) so that the potential for snow or ice accumulation is negligible. [ASHRAE 90.1:6.4.3.7]
Where setback, zoned, humidity and cooling controls and equipment are provided, they shall be designed and installed in accordance with Section E 502.10 through Section E 502.10.3.1. [ASHRAE 90.2:6.10.3.3]
Whole house exhaust fans shall have insulated louvers or covers which close where the fan is off. Covers or louvers shall have an insulation value of not less than R-4.2, and shall be installed in accordance with the manufacturer's installation instructions. The attic openings shall be sufficient to accommodate the ventilation capacity of the whole house fan. The operation of the whole house fan shall be considered in determining the adequacy of providing combustion air in accordance with this code.
Dampers shall be installed to close off outdoor air inlets and exhaust outlets where the ventilation system is not operating.
The heating, ventilation, and air-conditioning in buildings, other than single-family houses, multifamily structures of not more than three stories above grade, and modular houses, shall be in accordance with Section E 503.0.
Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of new buildings shall be in accordance with the requirements of this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.1]
Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of additions to existing buildings shall be in accordance with the requirements of this section as described in Section E 503.2.

Exception: Where HVACR to an addition is provided by existing HVACR systems and equipment, such existing systems and equipment shall not be required to be in accordance with this appendix. A new system or equipment installed shall be in accordance with specific requirements applicable to those systems and equipment. [ASHRAE 90.1:6.1.1.2]
New HVACR equipment as a direct replacement of existing HVACR equipment shall be in accordance with the specific minimum efficiency requirements applicable to that equipment. [ASHRAE 90.1:6.1.1.3.1]
New cooling systems installed to serve previously uncooled spaces shall be in accordance with this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.3.2]
Alterations to existing cooling systems shall not decrease economizer capability unless the system is in accordance with Section E 503.5 through Section 503.5.4.1. [ASHRAE 90.1:6.1.1.3.3]
New and replacement ductwork shall comply with Section E 503.4.7.1 through Section E 503.4.7.2.1. [ASHRAE 90.1:6.1.1.3.4]
New and replacement piping shall comply with Section E 503.4.7.1.

Exceptions:
  1. For equipment that is being modified or repaired but not replaced, provided that such modifications or repairs will not result in an increase in the annual energy consumption of the equipment using the same energy type.
  2. Where a replacement or alteration of equipment requires extensive revisions to other systems, equipment, or elements of a building, and such replaced or altered equipment is a like-for-like replacement
  3. For a refrigerant change of existing equipment.
  4. For the relocation of existing equipment.
  5. For ducts and piping where there is insufficient space or access to comply with these requirements. [ASHRAE 90.1:6.1.1.3.5]
Section E 503.0 shall be achieved in accordance with the requirements of Section E 503.1.1 through Section E 503.1.3.4, Section E 503.6, Section E 503.7, and one of the following:
  1. Section E 503.3 and Section E 503.3.1
  2. Section E 503.4
  3. Section E 503.4 and Section E 503.8 [ASHRAE 90.1:6.2.1]
Projects using the energy cost budget method in accordance with ASHRAE 90.1 shall comply with Section E 503.4. the mandatory provisions of this section, as a portion of that compliance path. [ASHRAE 90.1:6.2.2]
The simplified approach shall be an optional path for compliance where the following conditions are met:
  1. The building is not more than two stories in height.
  2. Gross floor area is less than 25000 square feet (2322.6 m2).
  3. The HVAC system in the building is in accordance with the requirements listed in Section E 503.3.1. [ASHRAE 90.1:6.3.1]
The HVAC system shall comply with the following criteria:
  1. The system serves a single HVAC zone.
  2. Thc equipment shall comply with the variable flow requirements of Section E 503.5.6.2.
  3. Cooling (where any) shall be provided by a unitary packaged or split-system air conditioner that is either air-cooled or evaporatively cooled, with efficiency that is in accordance with the requirements shown in Table E 503.7.1(1), Table E 503.7.1(2), or Table E 503.7.1(4) for the applicable equipment category.
  4. The system shall have an air economizer in accordance with Section E 503.5 through Section E 503.5.4.1.
  5. Heating (where any) shall be provided by a unitary packaged or split-system heat pump that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(2) or Table E 503.7.1(4), a fuel-fired furnace that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(5), an electric resistance heater, or a baseboard system connected to a boiler that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(6).
  6. The system shall comply with the exhaust air energy requirements in accordance with Section E 503.5.10.
  7. The system shall be controlled by a manual changeover or dual setpoint thermostat.
  8. Where a heat pump equipped with auxiliary internal electric resistance heaters is installed, controls shall be provided that prevent supplemental heater operation where the heating load is capable of being met by the heat pump alone during both steady-state operation and setback recovery. Supplemental heater operation shall be permitted during outdoor coil defrost cycles. The heat pump shall be controlled in accordance with one of the following:

    1. A digital or electronic thermostat designed for heat pump use that energizes auxiliary heat where the heat pump has insufficient capacity to maintain setpoint or to warm up the space at a sufficient rate.
    2. A multistage space thermostat and an outdoor air thermostat wired to energize auxiliary heat on the last stage of the space thermostat and where outdoor air temperature is less than 40°F (4°C).
    Exceptions: Heat Pumps that comply with the following:

    1. Have minimum efficiency regulated by NAECA.
    2. In accordance with the requirements shown in Table E 503.7.1(2).
    3. Includes usage of internal electric resistance heating.
  9. The system controls shall not permit reheat or other form of simultaneous heating and cooling for humidity control.
  10. Systems serving spaces other than hotel or motel guest rooms, and other than those requiring continuous operation, which have both a cooling or heating capacity more than 15000 Btu/h (4.4 kW) and a supply fan motor power more than 0.75 horsepower (hp) (0.56 kW), shall be provided with a time clock that is in accordance with the following:

    1. Can start and stop the system under different schedules for seven different day-types per week.
    2. Capable of retaining programming and time setting during a loss of power for a period of not less than 10 hours.
    3. Includes an accessible manual override that allows temporary operation of the system for up to 2 hours.
    4. Capable of temperature setback down to 55°F (13°C) during off hours.
    5. Capable of temperature setup to 90°F (32°C) during off hours.
  11. Except for piping within manufacturer's units, HVAC piping shall be insulated in accordance with Table E 503.7.3(1) and Table E 503.7.3(2). Insulation exposed to weather shall be suitable for outdoor service (e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover). Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation.
  12. Ductwork and plenums shall be insulated in accordance with Table E 503.7.2(1) and Table E 503.7.2(2) and shall be sealed in accordance with Section E 503.4.7.2.
  13. Construction documents shall require a ducted system to be air balanced in accordance with industry-accepted procedures.
  14. Outdoor air intake and exhaust systems shall comply with Section E 503.4.6.4 through Section E 503.4.6.5.
  15. Where separate heating and cooling equipment serves the same temperature zone, thermostats shall be interlocked to prevent simultaneous heating and cooling.
  16. Systems with a design supply air capacity more than 10000 ft3/min (4.7195 m3/s) shall have optimum start controls.
  17. The system shall comply with the demand control ventilation requirements of Section E 503.4.6.9.
  18. The system shall comply with the door switch requirements of Section E 503.5.14. [ASHRAE 90.1:6.3.2]
Climate zones identified in this appendix shall be determined in accordance with ASHRAE 90.1.

Exception: Where recorded historical climatic data are available for a construction site, it is permitted to be used to determine compliance where approved by the Authority Having Jurisdiction. [ASHRAE 90.1:5.1.4.1]
Equipment shown in Table E 503.7.1(1) through Table E 503.7.1(13) shall have a minimum performance at the specified rating conditions where tested in accordance with the specified test procedure. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy the stated requirements, unless otherwise exempted by footnotes in the table. Equipment covered under the Federal Energy Policy Act of 1992 (EPACT) shall have no minimum efficiency requirements for operation at minimum capacity or other than standard rating conditions. Equipment used to provide water heating functions as part of a combination system shall satisfy the stated requirements for the appropriate space heating or cooling category.

Tables are as follows:
  1. Table E 503.7.1(1) - Electrically Operated Unitary Air Conditioners and Condensing Units
  2. Table E 503.7.1(2) - Electrically Operated Unitary and Applied Heat Pumps
  3. Table E 503.7.1(3) Water-Chilling (see Section E 503.4.1 for water-cooled centrifugal water-chilling packages that are designed to operate at nonstandard conditions)
  4. Table E 503.7.1 (4) - Electrically Operated Packaged Terminal Air Conditioners, Packaged Terminal Heat Pumps, Single Package Vertical Air Conditioners, Single-Package Vertical Heat Pumps, Room Air Conditioners and, Room Air Conditioner Heat Pumps
  5. Table E 503.7.1(5) - Warm-Air Furnaces, Warm-Air Furnaces/Air-Conditioning Units, Warm-Air Duct Furnaces, and Unit Heaters
  6. Table E 503.7.1(6) - Gas- and Oil-Fired Boilers
  7. Table E 503.7.1(7) - Perfonnance Requirements for Heat Rejection Equipment
  8. Table E 503.7.1(8) - Heat Transfer Equipment
  9. Table E 503.7.1(9) - Electrically Operated VariableRefrigerant-Flow Air Conditioners
  10. Table E 503.7.1(10) - Electrically Operated Variab1e-Refrigerant-Flow Air-to-Air and Applied Heat Pump
  11. Table E 503.7.1(11) - Air Conditioners and Condensing Units Serving Computer Rooms
  12. Table E 503.7.1(12) - Commercial Refrigerators and Freezers
  13. Table E 503.7.1(13) - Commercial Refrigeration
    Furnaces with input ratings of not less than 225000 Btu/h (66 kW), including electric furnaces, that are not located within the conditioned space shall have jacket losses not exceeding 0.75 percent of the input rating. Air conditioners primarily serving computer rooms under the scope of ASHRAE 127 shall be in accordance with Table E 503.7.1(11). Other air conditioners shall comply with Table E 503.7.1(1). [ASHRAE 90.1:6.4.1.1]
Equipment not designed for operation in accordance with AHRI 550/590 test conditions of 44°F (7°C) leaving chilled fluid temperature and 2.4 gallons per minute per ton (gpm/ton) (0.00015 L/s/kg) evaporator fluid flow and 85°F (29°C) entering condenser-fluid temperature with 3.0 gpm/ton (0.00018 L/s/kg) condenser-fluid flow shall have maximum full-load kW/ton (FL) and part-load rating requirements adjusted in accordance with Equation E 503.4.1(1) through Equation E 503.4.1(3):

FLadj = FL/Kadj       [Equation E 503.4.1(1)]
PLVadj = IPLV/Kadj [Equation E 503.4.1(2)]
Kadj = A x B             [Equation E 503.4.1(3)]
Where:
FL = full-load kW/ton value from Table E
503.7.1(3)
FLadj = maximum full-load kW/ton rating, adjusted
for nonstandard conditions
IPLV = IPLV value from Table E 503.7.1(3)
IPLVadj = maximum NPLV rating, adjusted for
nonstandard conditions

A = 0.000000014592 x (LIFT)4 - 0.0000346496 x (LIFT)3 + 0.00314196 x (LIFT)2 - 0.147199 x (LIFT) + 3.9302

B = 0.0015 x LvgEvap + 0.934

LIFT = LvgCond - LvgEvap

LvgCond = Full-load condenser leaving fluid temperature (°F)

LvgEvap = Full-load evaporator leaving temperature (°F)

    The FLadj and PLVadj values shall only be applicable for cenfrifugal chillers in accordance with the following full-load design ranges:
  1. Minimum Evaporator Leaving Temperature: 36°F (2°C)
  2. Maximum Condenser Leaving Temperature: 115°F (46°C)
  3. LIFT is not less than 20°F (-6°C) and not more than 80°F (27°C)
    Manufacturers shall calculate the FLadj and PLVadj before determining whether to label the chiller in accordance with Section E 503.4.4. Chillers that are in accordance with ASHRAE 90.1 shall be labeled on chillers in accordance with the scope of ASHRAE 90.1.

    Centrifugal chillers designed to operate outside of these ranges shall not be covered under this appendix.

Example: Path A, 600 ton (600000 kg) centrifugal chiller Table E 503.7.1(3) efficiencies.
F = 0.560 kW/ton
IPLV = 0.500 kW/ton
LvgCond = 91.16°F
LvgEvap = 42°F
LIFT = 91.16°F - 42°F = 49.16°F
Kadj = A x B
A = 0.00000014592 x (49.1.6)4 - 0.0000346496 x
(49.16)3 + 0.00314196 x (49.16)2 - 0.147199
x (49.16) + 3.9302 = 1.0228
B = 0.0015 x 42 + 0.934 = 0.9970
FLadj = 0.560/(1.0228 x 0.9970) = 0.549 kW/ton
PLVadj = 0.500/(1.0228 x 0.9970) = 0.490 kW/ton
[ASHRAE 90.1:6.4.1.2.1]
For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW, 1 gallon per minute = 0.06 L/s, °C = (°F-32)/1.8
Equipment with an evaporator leaving fluid temperature more than 32°F (0°C) and water-cooled positive displacement chilling packages with a condenser leaving fluid temperature less than 115°F (46°C) shall be in accordance with Table E 503.7.1(3) where tested or certified with water at standard rating conditions, in accordance with the referenced test procedure. [ASHRAE 90.1:6.4.1.2.2]
Equipment not listed in the tables referenced in Section E 503.4 and Section E 503.4.1 shall be permitted to be used. [ASHRAE 90.1:6.4.1.3]
Equipment efficiency information supplied by manufacturers shall be verified in accordance with one of the following:
  1. Equipment covered under EPACT shall be in accordance with U.S. Department of Energy certification requirements.
  2. Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, then the product shall be listed in the certification program.
  3. Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, but the product is not listed in the existing certification program, the ratings shall be verified by an independent laboratory test report.
  4. Where no certification program exists for a covered product, the equipment efficiency ratings shall be supported by data furnished by the manufacturer.
  5. Where components such as indoor or outdoor coils from different manufacturers are used, the system designer shall specify component efficiencies whose combined efficiency is in accordance with the minimum equipment efficiency requirements in Section E 503.4 through Section E 503.4.4.1.
  6. Requirements for plate-type liquid-to-liquid heat exchangers are listed in Table E 503.7.1(8). [ASHRAE 90.1:6.4.1.4]
Mechanical equipment that is not covered by the U.S. National Appliance Energy Conservation Act (NAECA) of 1987 shall carry a permanent label installed by the manufacturer stating that the equipment is in accordance with the requirements of ASHRAE 90.1. [ASHRAE 90.1:6.4.1.5.1]
Nonstandard-size packaged terminal air conditioners and heat pumps with existing sleeves having an external wall opening of less than 16 inches (406 mm) high or less than 42 inches (1067 mm) wide and having a cross-sectional area less than 670 square inches (0.432 m2) shall be factory labeled in accordance with the following:

"Manufactured for nonstandard-size applications only: not to be installed in new construction projects." [ASHRAE 90.1:6.4.1.5.2]
Heating and cooling system design loads for the purpose of sizing systems and equipment shall be determined in accordance with ASHRAE/ACCA 183. [ASHRAE 90.1:6.4.2.1]
Pump differential pressure (head) for the purpose of sizing pumps shall be determined in accordance with generally accepted engineering standards and handbooks acceptable to the Authority Having Jurisdiction. The pressure drop through a device and pipe segment in the critical circuit at design conditions shall be calculated. [ASHRAE 90.1:6.4.2.2]
The supply of heating and cooling energy to each zone shall be individually controlled by thermostatic controls responding to temperature within the zone. For the purposes of Section E 503.4.6, a dwelling unit shall be permitted to be considered a single zone.

Exceptions: Independent perimeter systems that are designed to offset only building envelope loads shall be permitted to serve one or more zones also served by an interior system provided:
  1. The perimeter system includes not less than one thermostatic control zone for each building exposure having exterior walls facing only one orientation for 50 contiguous feet (15240 mm) or more.
  2. The perimeter system heating and cooling supply is controlled by a thermostatic control(s) located within the zones(s) served by the system.
    Exterior walls are considered to have different orientations where the directions they face differ by more than 45 degrees (0.79 rad). [ASHRAE 90.1:6.4.3.1.1]
Where used to control both heating and cooling, zone thermostatic controls shall be capable of providing a temperature range or dead band of not less than 5°F (3°C) within which the supply of heating and cooling energy to the zone is shut off or reduced to a minimum.

Exceptions:
  1. Thermostats that require manual changeover between heating and cooling modes.
  2. Special occupancy or special applications where wide temperature ranges are not acceptable (such as retirement homes, process applications, museums, some areas of hospitals) and are approved by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.1.2]
Where the heating and cooling to a zone are controlled by separate zone thermostatic controls located within the zone, means (such as limit switches, mechanical stops, or, for DDC systems, software programming) shall be provided to prevent the heating setpoint from exceeding the cooling setpoint minus an applicable proportional band. [ASHRAE 90.1:6.4.3.2]
HVAC systems shall have the off-hour controls required by Section E 503.4.6.3.1 through Section E 503.4.6.3.4.

Exceptions:
  1. HVAC systems intended to operate continuously.
  2. HVAC systems having a design heating capacity and cooling capacity less than 15000 Btu/h (4.4 kW) that are equipped with readily accessible manual ON/OFF controls. [ASHRAE 90.1:6.4.3.3]
HVAC systems shall be equipped with not less than one of the following:
  1. Controls that can start and stop the system under different time schedules for seven different day-types per week, are capable of retaining programming and time setting during loss of power for a period of not less than 10 hours, and include an accessible manual override, or equivalent function, that allows temporary operation of the system for up to 2 hours.
  2. An occupant sensor that is capable of shutting the system off where no occupant is sensed for a period of up to 30 minutes.
  3. A manually operated timer capable of being adjusted to operate the system for up to 2 hours.
  4. An interlock to a security system that shuts the system off where the security system is activated.
Exception: Residential occupancies shall be permitted to use controls that can start and stop the system under two different time schedules per week. [ASHRAE 90.1:6.4.3.3.1]
Heating systems shall be equipped with controls configured to automatically restart and temporarily operate the system as required to maintain zone temperatures above an adjustable heating setpoint of not less than 10°F (6°C) below the occupied heating setpoint. Cooling systems shall be equipped with controls configured to automatically restart and temporarily operate the mechanical cooling system as required to maintain zone temperatures below an adjustable cooling setpoint of not less than 5°F (3°C) above the occupied cooling setpoint or to prevent high space humidity levels.

Exception: Radiant heating systems configured with a setback heating setpoint at not less than 4°F (2°C) below the occupied heating setpoint. [ASHRAE 90.1:6.4.3.3.2]
Individual heating and cooling systems with setback controls and DDC shall have optimum start controls. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied setpoint, the outdoor air temperature, and the amount of time prior to scheduled occupancy. Mass radiant floor slab systems shall incorporate floor temperature into the optimum start algorithm. [ASHRAE 90.1:6.4.3.3.3]
HVAC systems serving zones that are intended to operate or be occupied nonsimultaneously shall be divided into isolation areas. Zones shall be permitted to be grouped into a single isolation area provided it does not exceed 25000 square feet (2322.6 m2) of conditioned floor area and does not include more than one floor. Each isolation area shall be equipped with isolation devices capable of automatically shutting off the supply of conditioned air and outdoor air to and exhaust air from the area. Each isolation area shall be controlled independently by a device meeting the requirements of Section E 503.4.6.3.1. For central systems and plants, controls and devices shall be provided to allow stable system and equipment operation for a length of time while serving the smallest isolation area served by the system or plant.

Exceptions: Isolation devices and controls are not required for the following:
  1. Exhaust air and outdoor air connections to isolation zones where the fan system to which they connect is not more than 5000 ft3/min (2.3597 m3/s).
  2. Exhaust airflow from a single isolation zone of less than 10 percent of the design airflow of the exhaust system to which it connects.
  3. Zones intended to operate continuously or intended to be inoperative where other zones are inoperative. [ASHRAE 90.1:6.4.3.3.4]
Stair and elevator shaft vents shall be equipped with motorized dampers that are capable of being automatically closed during normal building operation and are interlocked to open in accordance with fire and smoke detection systems. [ASHRAE 90.1:6.4.3.4.1]
Outdoor air intake and exhaust systems shall be equipped with motorized dampers that will automatically shut where the systems or spaces served are not in use. Ventilation outdoor air, and exhaust or relief dampers shall be capable of automatically shutting off during preoccupancy building warm-up, cooldown, and setback, except where ventilation reduces energy costs or where ventilation shall be supplied to be in accordance with the requirements of this code.

Exceptions:
  1. Backdraft gravity (nonmotorized) dampers shall be permitted for exhaust and relief in buildings less than three stories in height, and for ventilation air intakes and exhaust and relief dampers in buildings of any height located in climate zones 1 through zone 3. Backdraft dampers for ventilation air intakes shall be protected from direct exposure to wind.
  2. Backdraft gravity (nonmotorized) dampers shall be permitted in systems with a design outdoor air intake or exhaust capacity of 300 ft3/min (0.142 m3/s) or less.
  3. Dampers shall not be required in ventilation or exhaust systems serving unconditioned spaces.
  4. Dampers shall not be required in exhaust systems serving Type 1 kitchen exhaust hoods. [ASHRAE 90.1:6.4.3.4.2]
Where outdoor air supply, and exhaust or relief dampers are required in Section E 503.4.6.4, they shall have a maximum leakage rate in accordance with Table E 503.4.6.4.2 where tested in accordance with AMCA 500. [ASHRAE 90.1:6.4.3.4.3]

TABLE E 503.4.6.4.2
MAXIMUM DAMPER LEAKAGE
(cubic foot per minute per square foot) at 1.0 in. w.g.
[ASHRAE 90.1: TABLE 6.4.3.4.3]
CLIMATE ZONE VENTILATION AIR INTAKE EXHAUST/RELIEF
NONMOTORIZED* MOTORIZED NONMOTORIZED* MOTORIZED
1, 2
any height
-
20
-
4
-
20
-
4
3
any height
-
20
-
10
-
20
-
10
4, 5b, 5c
less than 3 stories
3 or more stories
-
not allowed
not allowed
-
10
10
-
20
not allowed
-
10
10
5a, 6, 7, 8
less than 3 stories
3 or more stories
-
not allowed
not allowed
-
4
4
-
20
not allowed
-
4
4
For SI units: 1 cubic foot per minute = 0.00047 m3/s, 1 square foot = 0.0929 m2, 1 inch water gauge = 0.249 kPa

*  Dampers smaller than 24 inches (610 mm) in either dimension shall be permitted to have leakage of 40 ft3/min per square foot [0.203 (m3/s)/m2].
Fans with motors more than 0.75 hp (0.56 kW) shall have automatic controls in accordance with Section E 503.4.6.3.1 that are capable of shutting off fans where not required.

Exception: HVAC systems intended to operate continuously. [ASHRAE 90.1:6.4.3.4.4]
Enclosed parking garage ventilation systems shall automatically detect contaminant levels and stage fans or modulate fan airflow rates to 50 percent or less of design capacity, provided acceptable contaminant levels are maintained.

Exceptions:
  1. Garages not more than 30000 square feet (2787.09 m2) with ventilation systems that do not utilize mechanical cooling or mechanical heating.
  2. Garages that have a garage area to ventilation system motor nameplate hp ratio that exceeds 1500 square feet per horsepower (ft2/hp) (186.8 m2/kW) and do not utilize mechanical cooling or heating.
  3. Where not permitted by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.4.5]
Heat pumps equipped with internal electric resistance heaters shall have controls that prevent supplemental heater operation where the heating load is capable of being met by the heat pump alone during both steady-state operation and setback recovery. Supplemental heater operation shall be permitted during outdoor coil defrost cycles.

Exception: Heat pumps whose minimum efficiency is regulated by U.S. National Appliance Energy Conservation Act (NAECA) and whose ratings are in accordance with the requirements shown in Table E 503.7.1(2) and includes the use of an internal electric resistance heating. [ASHRAE 90.1:6.4.3.5]
Humidity control shall prevent the use of fossil fuel or electricity to produce relative humidity (RH) more than 30 percent in the wannest zone served by the humidification system and to reduce the RH valve to less than 60 percent in the coldest zone served by the dehumidification system. Where a zone is served by a system or systems with both humidification and dehumidification capability, means (such as limit switches, mechanical stops, or, for DDC systems, software programming) shall be provided capable of preventing simultaneous operation of humidification and dehumidification equipment.

Exceptions:
  1. Zones served by desiccant systems, used with direct evaporative cooling in series.
  2. Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards and humidity controls are configured to maintain a deadband of not less than 10 percent RH where no active humidification or dehumidification takes place.
  3. Systems serving zones where humidity levels are required to be maintained with precision of not more than ± 5 percent RH to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.6]
Freeze protection systems, such as heat tracing of outdoor piping and heat exchangers, including self-regulating heat tracing, shall include automatic controls capable of shutting off the systems where outdoor air temperatures are more than 40°F (4°C) or where the conditions of the protected fluid will prevent freezing. Snow- and ice-melting systems shall include automatic controls capable of shutting off the systems where the pavement temperature is more than 50°F (10°C) and no precipitation is falling, and an automatic or manual control that will allow shutoff where the outdoor temperature is more than 40°F (4°C) so that the potential for snow or ice accumulation is negligible. [ASHRAE 90.1:6.4.3.7]
Demand control ventilation (DCV) shall be required for spaces that are more than 500 square feet (46.45 m2) and with a design occupancy for ventilation of not less than 25 people per 1000 square feet (92.9 m2) of floor area and served by systems with one or more of the following:
  1. An air-side economizer.
  2. An automatic modulating control of the outdoor air damper.
  3. A design outdoor airflow more than 3000 ft3/min (1.4158 m3/s).
Exceptions:
  1. Systems with exhaust air energy recovery in accordance with Section E 503.5.10.
  2. Multiple-zone systems without DDC of individual zones communicating with a central control panel.
  3. Systems with a design outdoor airflow less than 750 ft3/min (0.3540 m3/s).
  4. Spaces where more than 75 percent of the space design outdoor airflow is required for makeup air that is exhausted from the space or transfer air that is required for makeup air that is exhausted from other space(s).
  5. Spaces with one of the following occupancy categories in accordance with Chapter 4 or ASHRAE 62.1: correctional cells; daycare sickrooms; science labs; barbers; beauty and nail salons; and bowling alley seating. [ASHRAE 90.1:6.4.3.8]
Radiant heat systems shall be used to provide heat outdoors. Outdoor radiant heating systems shall be provided with controls that sense the presence of occupants or other device that automatically shuts down the system where no occupants are in the heating area.
HVAC Ducts shall be constructed in accordance with provisions contained in the SMACNA HVAC Duct Construction Standard. HVAC system construction and insulation shall comply with Section E 503.4.7.1 and Section E 503.4.7.2.
Insulation required by this section shall be installed in accordance with industry-accepted standards. These requirements shall not apply to HVAC equipment. Insulation shall be protected from damage, including that due to sunlight, moisture, equipment maintenance, and wind, but not limited to the following:
  1. Insulation exposed to weather shall be suitable for outdoor service (e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover). Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation that is capable of causing degradation of the material.
  2. Insulation covering chilled-water piping, refrigerant suction piping, or cooling ducts located outside the conditioned space shall include a vapor retardant located outside the insulation (unless the insulation is inherently vapor retardant), penetrations and joints of which shall be sealed. [ASHRAE 90.1:6.4.4.1.1]
Supply and return ducts and plenums installed as part of an HVAC air distribution system shall be thermally insulated in accordance with Table E 503.7.2(1) and Table E 503.7.2(2).

Exceptions:
  1. Factory-installed plenums, casings, or ductwork fumished as a part of HVAC equipment tested and rated in accordance with Section E 503.4 through Section E 503.4.4.1.
  2. Ducts or plenums located in heated spaces, semi-heated spaces, or cooled spaces.
  3. For runouts less than 10 feet (3048 mm) in length to air terminals or air outlets, the rated R-value of insulation shall not he required to exceed R-3.5.
  4. Backs of air outlets and outlet plenums exposed to unconditioned or indirectly conditioned spaces with face areas exceeding 5 square feet (0.5 m2) shall not be required to exceed R-2; those not exceeding 5 square feet (0.5 m2) shall not be required to be insulated. [ASHRAE 90.1:6.4.4.1.2]
Piping shall be thermally insulated in accordance with Table E 503.7.3(1) and Table E 503.7.3(2).

Exceptions:
  1. Factory-installed piping within HVAC equipment tested and rated in accordance with Section E 503.4 through Section E 503.4.4.1.
  2. Piping that conveys fluids having a design operating temperature range between 60°F (16°C) and 105°F (41°C), inclusive.
  3. Piping that conveys fluids that have not been heated or cooled through the use of fossil fuels or electricity (such as roof and condensate drains, domestic cold water supply, or natural gas piping).
  4. Where heat gain or heat loss will not increase energy usage (such as liquid refrigerant piping).
  5. For piping 1 inch (25 mm) or less, insulation shall not be required for strainers, control valves, and balancing valves. [ASHRAE 90.1:6.4.4.1.3]
Thermally ineffective panel surfaces of sensible heating panels, including U-bends and headers, shall be insulated with not less than R-3.5. Adjacent building envelope insulation shall be applied to this insulation value. [ASHRAE 90.1:6.4.4.1.4]
The bottom surfaces of floor structures incorporating radiant heating shall be insulated not less than R-3.5. Adjacent building envelope insulation shall be applied to this insulated value.

Exception: Heated slab-on-grade floors incorporating radiant heating shall be in accordance with ASHRAE 90.1. [ASHRAE 90.1:6.4.4.1.5]
Ductwork and plenums with pressure class ratings shall be constructed to Seal Class A in accordance with Section E 503.4.7.2.1, and with standard industry practice. Openings for rotating shafts shall be sealed with bushings or devices that seal off air leakage. Pressure-sensitive tape shall not be used as the primary sealant, unless it has been certified in accordance with UL 181A or UL 181B by an independent testing laboratory and the tape is used in, accordance with that certification. All connections shall be sealed, including but not limited to spin-ins, taps, other branch connections, access doors, access panels, and duct connections to equipment. Scaling that is capable of voiding the product listings shall not be required. Spiral lock seams shall be permitted to not be sealed. Duct pressure class ratings shall be designated in the design documents. [ASHRAE 90.1:6.4.4.2.1]
Ductwork that is designed to operate at static pressures exceeding 3 inches water column (0.7 kPa) and ductwork located outdoors shall be leak-tested in accordance with industry-accepted test procedures. Representative sections totaling not less than 25 percent of the total installed duct area for the designated pressure class shall be tested. Sections to be tested shall be selected by the building owner or designated representative of the building owner. Positive pressure leakage testing shall be acceptable for negative pressure ductwork. The permitted duct leakage shall be not more than the following:

Lmax = CLP0.65 (Equation E 503.4.7.2.1)
Where:
Lmax = maximum permitted leakage,
( ft3/min)/100 square feet [0.0001
(m3/s)/m2] duct surface area.
CL = Six, duct leakage class, (ft3/min)/100
square feet [0.0001 (m3/s)/m2] duct
surface area at 1 inch water column
(0.2 kPa).
P = test pressure, which shall be equal
to the design duct pressure class
rating, inch water column (kPa).
[ASHRAE 90.1:6.4.4.2.2]
Cooling systems that have fans shall include either an air or water economizer in accordance with Section E 503.5.1 through Section E 503.5.4.1.

Exceptions: Economizers shall not be required for the following systems:
  1. Individual fan-cooling units with a supply capacity less than the minimum listed in Table E 503.5(1) for comfort cooling applications and Table E 503.5(2) for computer room applications.
  2. Systems that include nonparticulate air treatment in accordance with ASHRAE 62.1.
  3. In hospitals and ambulatory surgery centers, where more than 75 percent of the air designed to be supplied by the system is to spaces that are required to be humidified more than 35°F (2°C) dew-point temperature in accordance with applicable codes or standards. In other buildings, where more than 25 percent of the air designed to be supplied by the system is to spaces that are designed to be humidified more than 35°F (2°C) dew-point temperature to satisfy process needs. This exception shall not apply to computer rooms.
  4. Systems that include a condenser heat recovery system with a minimum capacity in accordance with Section E 503.5.10.1.2.
  5. Systems that serve residential spaces where the system capacity is less than five times the requirement listed in Table E 503.5(1).
  6. Systems that serve spaces whose sensible cooling load at design conditions, excluding transmission and infiltration loads, is less than or equal to transmission and infiltration losses at an outdoor temperature of 60°F (16°C).
  7. Systems expected to operate less than 20 hours per week.
  8. Where the use of outdoor air for cooling will affect supermarket open refrigerated casework systems.
  9. For comfort cooling where the cooling efficiency is not less than the efficiency improvement requirements in accordance with Table E 503.5(3).
  10. Systems primarily serving computer rooms where in accordance with the following:

    1. The total design cooling load of computer rooms in the building is less than 3000000 Btu/h (879 kW) and the building in which they are located is not served by a centralized chilled water plant.
    2. The room total design cooling load is less than 600000 Btu/h (176 kW) and the building in which they are located is served by a centralized chilled water plant.
    3. The local water authority does not permit cooling towers.
    4. Less than 600000 Btu/h (176 kW) of computer room cooling equipment capacity is being added to an existing building.
  11. Dedicated systems for computer rooms where a minimum of 75 percent of the design load serves the following:

    1. Spaces classified as an essential facility.
    2. Spaces having a mechanical cooling design of Tier IV in accordance with TIA 942.
    3. Spaces classified as critical operations power systems (COPS) in accordance with NFPA 70.
    4. Spaces where core clearing and settlement services are performed such that their failure to settle pending financial transactions is capable of systemic risk in accordance with "The Interagency Paper on Sound Practices to Strengthen the Resilience of the US Financial System, April 7, 2003." [ASHRAE 90.1:6.5.1]
TABLE E 503.5(1)
MINIMUM FAN-COOLING UNIT SIZE WHERE AN ECONOMIZER
IS REQUIRED FOR COMFORT COOLING
[ASH RAE 90.1:TABLE 6.5.1-1]
CLIMATE ZONES COOLING CAPACITY WHERE AN
ECONOMIZER IS REQUIRED
1a, 1b No economizer requirement
2a, 2b, 3a, 4a, 5a, 6a, 3b, 3c,
4b, 4c, 5b, 5c, 6b, 7, 8
≥ 54000 Btu/h
For SI units: 1000 British thermal units per hour = 0.293 kW

TABLE E 503.5(2)
MINIMUM FAN-COOLING UNIT SIZE WHERE AN
ECONOMIZER IS REQUIRED FOR COMPUTER ROOMS
[ASHRAE 90.1: TABLE 6.5.1-2]
CLIMATE ZONES COOLING CAPACITY WHERE AN
ECONOMIZER IS REQUIRED
1a, 1b, 2a, 3a, 4a No economizer requirement
2b, 5a, 6a, 7, 8 ≥ 135000 Btu/h
3b, 3c, 4b, 5b, 5c, 6b ≥ 65000 Btu/h
For SI units: 1000 British thermal units per hour = 0.293 kW

TABLE E 503.5(3)
ELIMINATE REQUIRED ECONOMIZER FOR COMFORT
COOLING BY INCREASING COOLING EFFICIENCY
[ASHRAE 90.1: TABLE 6.5.1-3]
CLIMATE ZONE EFFIENCY IMPROVEMENT *
2a 17%
2b 21%
3a 27%
3b 32%
3c 65%
4a 42%
4b 49%
4c 64%
5a 49%
5b 59%
5c 74%
6a 56%
6b 65%
7 72%
8 77%
*  Where a unit rated with an IPLV, IEER or SEER, to eliminate the required air or water economizer, the minimum cooling efficiency of the HVAC unit shall be increased by the percentage shown. Where the HVAC unit is rated with a full load metric like EER or COP cooling, these shall be increased by the percentage shown.
Air economizer systems shall be capable of modulating outdoor air and return air dampers to provide up to 100 percent of the design supply air quantity as outdoor air for cooling. [ASHRAE: 90.1:6.5.1.1.1]
Economizer dampers shall be capable of being sequenced with the mechanical cooling equipment and shall not be controlled by only mixed air temperature.

Exception: The use of mixed air temperature limit control shall be permitted for systems controlled from space temperature (such as single-zone systems). [ASHRAE 90.1:6.5.1.1.2]
Air economizers shall be capable of automatically reducing outdoor air intake to the design minimum outdoor air quantity where outdoor air intake will no longer reduce cooling energy usage. High-limit shutoff control types and associated setpoints for specific climate zones shall be chosen from Table E 503.5.1.2. [ASHRAE 90.1:6.5.1.1.3]

TABLE E 503.5.1.2
HIGH-LIMIT SHUTOFF CONTROL SETTINGS FOR AIR ECONOMIZERS2
[ASHRAE 90.1: TABLE 6.5.1.1.3]
CONTROL TYPE ALLOWED ONLY IN
CLIMATE ZONE AT LISTED
SETPOINT
REQUIRED HIGH LIMIT (ECONOMIZER OFF WHERE):
EQUATION DESCRIPTION
Fixed dry bulb
temperature
1b, 2b, 3b, 3c,4b, 4c, 5b, 5c, 6b,
7, 8
Toa > 75°F Outdoor air temperature exceeds 75°F
5a, 6a Toa > 70°F Outdoor air temperature exceeds 70°F
1a, 2a, 3a, 4a Toa > 65°F Outdoor air temperature exceeds 65°F
Differential dry bulb
temperature
1b, 2b, 3b, 3c, 4b, 4c, 5a, 5b, 5c, 6a, 6b,
7, 8
Toa > Tra Outdoor air temperature exceeds return air temperature
Fixed enthalpy with
fixed dry-bulb
temperature
All hoa > 28 Btu/lb1 or Toa > 75°F Outdoor air enthalpy exceeds 28 Btu/lb1 of dry
air1 or outdoor air temperature exceeds 75°F
Differential enthalpy
with fixed dry-bulb
temperature
All hoa > hra or Toa > 75°F Outdoor air enthalpy exceeds return air enthalpy or outdoor air temperature exceeds 75°F
For SI units: °C = (°F-32)/1.8, 1 British thermal umt per pound = 2326 J/kg

Notes:
1   At altitudes substantially different than sea level, the fixed enthalpy limit shall be set to the enthalpy value at 75°F (24°C) and 50 percent relative humidity. As an example, at approximately 6000 feet (1829 m) elevation, the fixed enthalpy limit shall be approximately 30.7 Btu/lb (71408 J/kg).
2   Devices with selectable rather than adjustable setpoints shall be capable of being set to within 2°F (1°C) and 2 Btu/lb (4649 J/kg) of the setpoint listed.
Return air, exhaust or relief, and outdoor air dampers shall comply with Section E 503.4.6.4.2. [ASHRAE 90.1:6.5.1.1.4]
Systems shall provide a means to relieve excess outdoor air during air economizer operation to prevent over-pressurizing the building. The relief air outlet shall be located to avoid recirculation into the building. [ASHRAE 90.1:6.5.1.1.5]
Water economizer systems shall be capable of cooling supply air by indirect evaporation and providing up to 100 percent of the expected system cooling load at outdoor air temperatures of not more than 50°F (10°C) dry bulb or 45°F (7°C) wet bulb.

Exceptions:
  1. Systems primarily serving computer rooms in which 100 percent of the expected system cooling load at the dry bulb and wet bulb in accordance with Table E 503.5.2 is achieved with evaporative water economizers.
  2. Systems primarily serving computer rooms in which 100 percent of the expected system cooling load at the dry bulb temperatures in accordance with Table E 503.5.2 is achieved with dry cooler water economizers.
  3. Systems where dehumidification requirements are not capable of being met using outdoor air temperatures of 50°F (10°C) dry bulb or 45°F (7°C) wet bulb, and where 100 percent of the expected system cooling load at 45°F (7°C) dry bulb or 40°F (4°C) wet bulb is achieved with evaporative water economizers. [ASHRAE 90.1:6.5.1.2.1]
TABLE E 503.5.2
WATER ECONOMIZER SIZING DRY-BULB AND WET-BULB REQUIREMENTS FOR COMPUTER ROOMS*
[ASHRAE 90.1:TABLE 6.5.1.2.1]
ZONE EVAPORATIVE WATER ECONOMIZER DRY COOLER WATER
ECONOMIZER
DRY BULB, °F WET BULB, °F DRY BULB, °F
1 A NR NR
1 B NR NR
2 A 40.0 35.0 30.0
2 B 35.0 30.0 30.0
3 A 40.0 35.0 25.0
3 B 30.0 25.0 25.0
3 C 30.0 25.0 30.0
4 A 40.0 35.0 25.0
4 B 30.0 25.0 25.0
4 C 30.0 25.0 25.0
5 A 40.0 35.0 20.0
5 B 30.0 25.0 20.0
5 C 30.0 25.0 25.0
6 A 35.0 30.0 20.0
6 B 30.0 25.0 20.0
7 - 30.0 25.0 20.0
8 - 30.0 25.0 20.0
For SI units: °C = (°F-32)/1.8
NR = Not Required
Precooling coils and water-to-water heat exchangers used as part of a water economizer system shall either have a water-side pressure drop of less than 15 feet of water (45 kPa), or a secondary loop shall be created so that the coil or heat exchanger pressure drop is not seen by the circulating pumps where the system is in the normal cooling (non-economizer) mode. [ASHRAE 90.1:6.5.1.2.2]
Economizer systems shall be integrated with the mechanical cooling system and be capable of providing partial cooling even where additional mechanical cooling is required to be in accordance with the remainder of the cooling load. Controls shall not false load the mechanical cooling systems by limiting or disabling the economizer or by other means, such as hot gas bypass, except at the lowest stage of mechanical cooling.

    Units that include an air economizer shall comply with the following:
  1. Unit controls shall have the mechanical cooling capacity control interlocked with the air economizer controls such that the outdoor air damper is at the 100 percent open position when mechanical cooling is on, and the outdoor air damper does not begin to close to prevent coil freezing due to minimum compressor run time until the leaving air temperature is less than 45°F (7°C).
  2. DX units that control the capacity of the mechanical cooling directly based on occupied space temperature shall have a minimum of two stages of mechanical cooling capacity per the following effective dates:

    1. Not less than 75000 Btu/h (22kW) Rated Capacity-Effective 1/1/2014
    2. Not less than 65000 Btu/h (18kW) Rated Capacity-Effective 1/1/2016 [ASHRAE 90.1:6.5.1.3]
HVAC system design and economizer controls shall be such that economizer operation does not increase the building heating energy use during normal operation.

Exception: Economizers on variable air valve (VAV) systems that cause zone level heating to increase due to a reduction in supply air temperature. [ASHRAE 90.1:6.5.1.5]
Systems with hydronic cooling and humidification systems designed to maintain inside humidity at a dew-point temperature more than 35°F (2°C) shall use a water economizer where an economizer is required in accordance with Section E 503.5 through Section 503.5.4.1. [ASHRAE 90.1:6.5.1.6]
Zone thermostatic controls shall prevent the following:
  1. Reheating.
  2. Recooling.
  3. Mixing or simultaneously supplying air that has been previously mechanically heated and air that has been previously cooled, either by mechanical cooling or by economizer systems.
  4. Other simultaneous operation of heating and cooling systems to the same zone.

    Exceptions:
    1. Zones without DDC for which the volume of air that is reheated, recooled, or mixed is less than the larger of the following:

      1. Thirty percent of the zone design peak supply rate.
      2. The outdoor airflow rate required to be in accordance with the ventilation requirements of Chapter 4 or ASHRAE 62.1 for the zone.
      3. A higher rate that is capable of demonstrating, to the satisfaction of the Authority Having Jurisdiction, to reduce overall system annual energy usage by offsetting reheat or recool energy losses through a reduction in outdoor air intake for the system.
      4. The airflow rate required to be in accordance with applicable codes or accreditation standards, such as pressure relationships or minimum air change rates.
    2. Zones with DDC that comply with the following:

      1. The airflow rate in dead band between heating and cooling does not exceed the larger ofthe following:

        1. Twenty percent of the zone design peak supply rate.
        2. The outdoor airflow rate required to be in accordance with the ventilation requirements of Chapter 4 or ASHRAE 62.1 for the zone.
        3. A higher rate that is capable of demonstrating, to the satisfaction of the Authority Having Jurisdiction, to reduce overall system annual energy usage by offsetting reheat or recool energy losses through a reduction in outdoor air intake.
        4. The airflow rate required in accordance with applicable codes or accreditation standards, such as pressure relationships or minimum air change rates.
      2. The airflow rate that is reheated, recooled, or mixed shall be less than 50 percent of the zone design peak supply rate.
      3. The first stage of heating consists of modulating the zone supply air temperature setpoint up to a maximum setpoint while the airflow is maintained at the dead band flow rate.
      4. The second stage of heating consists of modulating the airflow rate from the dead band flow rate up to the heating maximum flow rate.
    3. Laboratory exhaust systems in accordance with Section E 503.5.11.3.
    4. Zones where not less than 75 percent of the energy for reheating or for providing warm air in mixing systems is provided from a site-recovered (including condenser heat) or site-solar energy source. [ASHRAE 90.1:6.5.2.1]
Where reheating is permitted in accordance with this appendix, zones that have both supply and return or exhaust air openings more than 6 feet (1829 mm) above the floor shall not supply heating air more than 20°F (11°C) above the space temperature setpoint.

Exceptions:
  1. Laboratory exhaust systems in accordance with Section E 503.5.11.3.
  2. During preoccupancy building warm-up and setback. [ASHRAE 90.1:6.5.2.1.1]
The heating of fluids in hydronic systems that have been previously mechanically cooled and the cooling of fluids that have been previously mechanically heated shall be limited in accordance with Section E 503.5.5.2.1 through Section E 503.5.5.2.3. [ASHRAE 90.1:6.5.2.2]
Hydronic systems that use a common return system for both hot water and chilled water shall not be used. [ASHRAE 90.1:6.5.2.2.1]
Systems that use a common distribution system to supply both heated and chilled water are acceptable where in accordance with the following:
  1. The system is designed to allow a dead band between changeover from one mode to the other of not less than 15°F (8°C) outdoor air temperature.
  2. The system is designed to operate and is provided with controls that will allow operation in one mode for not less than 4 hours before changing over to the other mode.
  3. Reset controls arc provided that allow heating and cooling supply temperatures at the changeover point to be not more than 30°F (17°C) apart. [ASHRAE 90.1:6.5.2.2.2]
Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection (e.g., cooling tower) and heat addition (e.g., boiler) shall have the following:
  1. Controls that are capable of providing a heat pump water supply temperature dead band of not less than 20°F (11°C) between initiation of heat rejection and heat addition by the central devices (e.g., tower and boiler).
  2. For climate zone 3 through zone 8, where a closed-circuit tower (fluid cooler) is used, either an automatic valve shall be installed to bypass all but a minimal flow of water around the tower (for freeze protection) or low-leakage positive closure dampers shall be provided. Where an open-circuit tower is used directly in the heat pump loop, an automatic valve shall be installed to bypass heat pump water flow around the tower. Where an open-circuit tower is used in conjunction with a separate heat exchanger to isolate the tower from the heat pump loop, then heat loss shall be controlled by shutting down the circulation pump on the cooling tower loop.

    Exception: Where a system loop temperature optimization controller is used to determine the most efficient operating temperature based on real-time conditions of demand and capacity, dead bands of less than 20°F (11°C) shall be permitted. [ASHRAE 90.1:6.5.2.2.3]
Where humidity controls are provided, such controls shall prevent reheating, mixing of hot and cold airstreams, or other means of simultaneous heating and cooling of the same airstream.

Exceptions:
  1. The system is configured to reduce supply air volume to 50 percent or less of the design airflow rate or the minimum outdoor air ventilation rate in accordance with ASHRAE 62.1 or other applicable federal, state, or local code or recognized standard, whichever is larger, before simultaneous heating and cooling takes place.
  2. The individual fan cooling unit has a design cooling capacity of not more than 65000 Btu/h (19 kW) and is capable of unloading to 50 percent capacity before simultaneous heating and cooling takes place.
  3. The individual mechanical cooling unit has a design cooling capacity of not more than 40000 Btu/h (11.7 kW). An individual mechanical cooling unit is a single system composed of a fan or fans and a cooling coil capable of providing mechanical cooling.
  4. Systems serving spaces where specific humidity levels are required to satisfy process needs, such as vivariums, museums, surgical suites, pharmacies, and buildings with refrigerating systems, such as supermarkets, refrigerated warehouses, and ice arenas, and the building includes site-recovered or site solar energy source that provide energy to 75 percent or more of the annual energy for reheating or for providing warm air in mixing systems. This exception shall not apply to computer rooms.
  5. Not less than 90 percent of the annual energy for reheating or for providing warm air in mixing systems is provided from a site-recovered (including condenser heat) or site-solar energy source.
  6. Systems where the heat added to the airstream is the result of the use of a desiccant system and 75 percent of the heat added by the desiccant system is removed by a heat exchanger, either before or after the desiccant system with energy recovery. [ASHRAE 90.1:6.5.2.3]
Humidifier with preheating jackets mounted in the airstream shall be provided with an automatic valve to shut off preheat where humidification is not required. [ASHRAE 90.1:6.5.2.4.1]
HVAC systems having a total fan system motor nameplate horsepower (hp) exceeding 5 hp (3.7 kW) shall be in accordance with the provisions of Section E 503.5.6.1 through Section E 503.5.6.5. [ASHRAE 90.1:6.5.3]
HVAC systems at fan system design conditions shall not exceed the allowable fan system motor nameplate horsepower (kW) (Option 1) or fan system brake horsepower (kW) (Option 2) as shown in Table E 503.5.6.1(1). This shall include supply fans, return or relief fans, exhaust fans, and fan powered terminal units associated with systems providing heating or cooling capability. Single-zone variable-air-volume systems shall comply with the constant-volume fan power limitation.

Exceptions:
  1. Hospital, vivarium, and laboratory systems that utilize flow control devices on exhaust, return, or both to maintain space pressure relationships necessary for occupant health and safety, or environmental control shall be permitted to use variable-volume fan power limitation.
  2. Individual exhaust fans with motor nameplate horsepower of 1 hp (0.7 kW) or less. [ASHRAE 90.1:6.5.3.1.1]
TABLE E 503.5.6.1(1)
FAN POWER LIMITATION*
[ASHRAE 90.1:TABLE 6.5.3.1
LIMIT CONSTANT VOLUME VARIABLE VOLUME
Option 1: Fan System
motor nameplate (hp)
Allowable nameplate
motor (hp)
hpCFMS • 0.0011 hpCFMS • 0.0015
Option 2: Fan system (bhp) Allowable fan system (bhp) bhpCFMS • 0.00094 + A bhpCFMS • 0.0013 + A
For SI units: 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m3/s

* Where:
CFMS = the maximum design supply airflow rate to conditioned spaces served by the system in cubic feet per minute (m3/s)
hp = the maximum combined motor nameplate horsepower (kW)
bhp = the maximum combined fan brake horsepower (kW)
A = sum of (PD x CFMD/4131)
PD = each applicable pressure drop adjustment from Table E 503.5.6.1(2) in inch water column (kPa)
CFMD = the design airflow through each applicable device from Table E 503.5.6.1(2) in cubic feet per minute (m3/s)


TABLE E 503.5.6.1(2)
FAN POWER LIMITATION PRESSURE DROP ADJUSTMENT
[ASHRAE 90.1:TABLE 6.5.3.1-2]
DEVICE ADJUSTMENT
CREDITS
Fully ducted return, exhaust, or both air systems 0.5 in. w.c. (2.15 in w.c. for laboratory and vivarium systems)
Return, exhaust, or both airflow control devices 0.5 in. w.c.
Exhaust filters, scrubbers, or other exhaust treatment The pressure drop of device calculated at fan system design condition
Particulate Filtration Credit: MERV 9 through 12 0.5 in. w.c.
Particulate Filtration Credit: MERV 13 through 15 0.9 in. w.c.
Particulate Filtration Credit: MERV 16 and greater, and electronically
enhanced filters
Pressure drop calculated at 2x clean fiIter pressure drop at fan
system design condition
Carbon and other gas-phase air cleaners Clean filter pressure drop at fan system design condition
Boisafety cabinet Pressure drop of device at fan system design condition
Energy recovery device, other than coil runaround loop (2.2 x energy recovery effectiveness) - 0.5 in w.c. for each airstream
Coil runaround loop 0.6 in. w.c. for each airstream
Evaporative humidifier or cooler in series with another cooling coil Pressure drop of device at fan system design condition
Sound attenuation section (fans serving spaces with design background
noise goals below (NC35)
0.15 in. w.c.
Exhaust system serving fume hoods 0.35 in. w.c.
Laboratory and vivarium exhaust systems in high-rise buildings 0.25 in. w.c. per 100 feet of vertical duct exceeding 75 ft
DEDUCTIONS
Systems without central cooling device -0.6 in. wc
Systems without central heating device -0.3 in. wc
Systems with central electric resistance heat -0.2 in. wc
For SI units: 1 inch water column = 0.249 kPa, 1 foot = 304.8 mm
For a fan, the selected fan motor shall be not larger than the first available motor size more than the brake horsepower (bhp) (kW). The fan brake horsepower shall be indicated on the design documents to allow for compliance verification by the Authority Having Jurisdiction.

Exceptions:
  1. For fans less than 6 bhp (4.5 kW), where the first available motor larger than the bhp (kW) has a nameplate rating within 50 percent of the bhp (kW), the next larger nameplate motor size shall be selected.
  2. For fans 6 bhp (4.5 kW) and larger, where the first available motor larger than the bhp (kW) has a nameplate rating with 30 percent of the bhp (kW), the next larger nameplate motor size shall be selected.
  3. Systems that are in accordance with Section E 503.5.6.1, Option 1. [ASHRAE 90.1:6.5.3.1.2]
Cooling systems listed in Table E 503.5.6.2 shall be designed to vary the indoor fan airflow as a function of load and shall be in accordance with the following:
  1. DX and chilled-water cooling units that control the capacity of the mechanical cooling directly based on space temperature shall have a minimum of two stages of fan control. Low or minimum speed shall not exceed 66 percent of full speed. At low or minimum speed, the fan system shall draw not more than 40 percent of the fan power at full fan speed. Low or minimum speed shall be used during periods of low cooling load and ventilation-only operation.
  2. Other units, including DX cooling units and chilled water units that control the space temperature by modulating the airflow to the space, shall have modulating fan control. Minimum speed shall not exceed 50 percent of full speed. At minimum speed, the fan system shall draw not more than 30 percent of the power at full fan speed. Low or minimum speed shall be used during periods of low cooling load and ventilation-only operation.
  3. Units that include an air-side economizer to comply with Section E 503.5 througb Section E 503.5.4.1 shall have not less than of two speeds of fan control during economizer operation.
Exceptions:
  1. Modulating fan control shall not be required for chilled-water and evaporative cooling units with less than 1 hp (0.7 kW) fan motors where the units are not used to provide ventilation air and the indoor fan cycles with the load.
  2. Where the volume of outdoor air required to comply with the ventilation requirements of Chapter 4 or ASHRAE 62.1 at low speed exceeds the air that would be delivered at the speed defined in Section E 503.5.6.2(1), or Section E 503.5.6.2(2), then the minimum speed shall be selected to provide the required ventilation air. [ASHRAE 90.1:6.5.3.2.1]

TABLE E 503.5.6.2
EFFECTIVE DATES FOR FAN CONTROL
[ASHRAE 90.1:TABLE 6.5.3.2.1]
COOLING SYSTEM TYPE FAN MOTOR SIZE, (hp) MECHANICAL COOLING
CAPACITY, (Btu/h)
EFFECTIVE DATE
DX cooling Any ≥ 110000
≥ 75000 1/1/2014
≥ 65000 1/1/2016
Chilled-water and evaporative
cooling
≥ 5 Any
14 Any 1/1/2014
For SI units: 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m3/s
Static pressure sensors used to control VAV fans shall be located such that the controller setpoint is not more than 1.2 inches water column (0.30 kPa). Where this results in the sensor being located downstream of major duct splits, sensors shall be installed in each major branch to ensure that static pressure is maintained in each.

Exception: Systems that are in accordance with Section E 503.5.6.2.2. [ASHRAE 90.1:6.5.3.2.2]
For systems with DDC of individual zone reporting to the central control panel static pressure setpoint shall be reset based on the zone requiring the most pressure, such as the setpoint is reset lower until one zone damper is nearly wide open. Controls shall provide the following:
  1. Monitor zone damper positions or other indicator of need for static pressure.
  2. Automatically detect those zones that are capable of excessively driving the reset logic and generate an alarm to the system operator.
  3. Readily allow operator removal of zone(s) from the reset algorithm. [ASHRAE 90.1:6.5.3.2.3]
Multiple-zone VAV systems with DDC individual zone boxes reporting to a central control panel shall include a means to automatically reduce outdoor air intake flow below design rates in response to changes in system ventilation efficiency in accordance with ASHRAE 62.1.

Exceptions:
  1. VAV systems with zonal transfer fans that recirculate air from other zones without directly mixing it with outdoor air, dual-duct dual-fan VAV systems, and VAV systems with fan-powered terminal units.
  2. Systems required to have the exhaust air energy recovery in accordance with Section E 503.5.10.
  3. Systems where total design exhaust airflow is more than 70 percent of total design outdoor air intake flow requirements. [ASHRAE 90.1:6.5.3.3]
Multiple zone HVAC systems shall include controls that automatically reset the supply air temperature in response to representative building loads, or to outdoor air temperature. The controls shall reset the supply air temperature to not less than 25 percent of the difference between the design supply air temperature and the design room air temperature. Controls that adjust the reset based on zone humidity shall be permitted. Zones that are expected to experience relatively constant loads, such as electronic equipment rooms, shall be designed for the fully reset supply temperature.

Exceptions:
  1. Climate zones 1a, 2a, and 3a.
  2. Systems that prevent reheating, recooling, or mixing of heated and cooled supply air.
  3. Systems where not less than 75 percent of the energy for reheating, on an annual basis, is from site recovered or site solar energy sources. [ASHRAE 90.1:6.5.3.4]
Motors for fans that are 112 hp (62.1 W) or more and less than 1 hp (0.7 kW) shall be electronically-commutated motors or shall have a motor efficiency of not less than 70 percent where rated in accordance with DOE 10 CFR 431. These motors shall also have the means to adjust motor speed for either balancing or remote control. Belt-driven fans shall be permitted to use sheave adjustments for airflow balancing in lieu of a varying motor speed.

Exceptions:
  1. Motors in the airstream within fan coils and terminal units that operate when providing heating to the space served.
  2. Motors installed in space conditioning equipment certified in accordance with Section E 503.4 through Section E 503.4.4.l.
  3. Motors shown in Table E 503.5.6.5(1) or Table E 503.5.6.5(2). [ASHRAE 90.1:6.5.3.5]
TABLE E 503.5.6.5(1)
MINIMUM AVERAGE FULL-LOAD EFFICIENCY FOR POLYPHASE SMALL ELECTRIC MOTORS*
[ASHRAE 90.1:TABLE 10.8-4]
FULL-LOAD EFFICIENCY FOR MOTORS MANUFACTURED ON OR AFTER MARCH 9, 2015, %
NUMBER OF POLES OPEN MOTORS
2 4 6
SYNCHRONOUS SPEED (RPM) 3600 1800 1200
MOTOR HORSEPOWER EFFICIENCY, %
0.25 65.6 69.5 67.5
0.33 69.5 73.4 71.4
0.50 73.4 78.2 75.3
0.75 76.8 81.1 81.7
1 77.0 83.5 82.5
1.5 84.0 86.5 83.8
2 85.5 86.5 N/A
3 85.5 86.9 N/A
*  Average full-load effic iencies shall be established in accordance with 10 CFR 431.


TABLE E 503.5.6.5(2)
MINIMUM AVERAGE FULL-LOAD EFFICIENCY FOR CAPACITOR-START CAPACITOR-RUN AND CAPACITOR-START INDUCTION-RUN SMALL ELECTRIC MOTORS*
[ASHRAE 90.1:TABLE 10.8-5]
FULL-LOAD EFFICIENCY FOR MOTORS MANUFACTURED ON OR AFTER MARCH 9, 2015, %
NUMBER OF POLES OPEN MOTORS
2 4 6
SYNCHRONOUS SPEED (RPM) 3600 1800 1200
MOTOR HORSEPOWER EFFICIENCY, %
0.25 66.6 68.5 62.2
0.33 70.5 72.4 66.6
0.50 72.4 76.2 76.2
0.75 76.2 81.8 80.2
1 80.4 82.6 81.1
1.5 81.5 83.8 N/A
2 82.9 84.5 N/A
3 84.1 N/A N/A
*  Average full-load efficiencies shall be established in accordance with 10 CFR 431.
Boiler systems with design input of 1000000 Btu/h (293 kW) or more shall comply with the turndown ratio in accordance with Table E 503.5.7.

    The system turndown requirement shall use multiple single-input boilers, one or more modulating boilers, or a combination of single-input and modulating boilers.

    Boilers shall comply with the minimum efficiency requirements in Table E 503.7.1(6). [ASHRAE 90.1:6.5.4.1]

TABLE E 503.5.7
BOILER TURNDOWN
[ASHRAE 90.1:TABLE 6.5.4.1]
BOILER SYSTEM DESIGN INPUT, Btu/h MINIMUM TURNDOWN RATIO
≥ 1000000 and ≥ 5000000 3 to 1
> 5000000 and ≤ 10000000 4 to 1
> 10000000 5 to 1
For SI units: 1000 British thermal units per hour = 0.293 kW
HVAC pumping systems having a total pump system power exceeding 10 hp (7.5 kW) that include control valves designed to modulate or step open and close as a function of load shall be designed for variable fluid flow and shall be capable of reducing pump flow rates to 50 percent or less of the design flow rate. Individual chilled-water pumps serving variable-flow systems having motors exceeding 5 hp (3.7 kW) shall have controls, devices, or both (such as variable-speed control) that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. The controls or devices shall be controlled as a function of desired flow or to maintain a minimum required differential pressure. Differential pressure shall be measured at or near the most remote heat exchanger or the heat exchanger requiring the greatest differential pressure. The differential pressure setpoint shall not exceed 110 percent of that required to achieve design flow through the heat exchanger. Where differential pressure control is used to be in accordance with this section, and DDC controls are used, the setpoint shall be reset downward based on valve positions until one valve is nearly wide open.

Exceptions:
  1. Systems where the minimum flow is less than the minimum flow required by the equipment manufacturcr for thc proper operation of equipment served by the system, such as chillers, and wherc total pump system power is 75 hp (55.9 kW) or less.
  2. Systems that include not more than three control valves. [ASHRAE 90.1:6.5.4.2]
Where a chilled-water plant includes more than one chiller, provisions shall be made so that the fluid flow through the chiller is automatically shut off where the chiller is shut down. Chillers piped in series for the purpose of increased temperature differential, shall be considered as one chiller. Where constant speed chilled-water or condenser water pumps are used to serve multiple chillers, the number of pumps shall be not less than the number of chillers and staged on and off with the chillers. [ASHRAE 90.1:6.5.4.3.1]
Where a boiler plant includes more than one boiler, provisions shall be made so that the flow through the boiler is automatically shut off where the boiler is shut down. Where constant-speed hot-water pumps are used to serve multiple boilers, the number of pumps shall be not less than the number of boilers and staged on and off with the boilers. [ASHRAE 90.1:6.5.4.3.2]
Chilled- and hot-water systems with a design capacity exceeding 300000 Btu/h (88 kW) supplying chilled or heated water (or both) to comfort conditioning systems shall include controls that automatically reset supply water temperatures by representative building loads (including return water temperature) or by outdoor air temperature.

Exceptions:
  1. Where the supply temperature reset controls are not capable of being implemented without causing improper operation of heating, cooling, humidifying, or dehumidifying systems.
  2. Hydronic systems, such as those required in Section E 503.5.7 that use variable flow to reduce pumping energy. [ASHRAE 90.1:6.5.4.4]
Hydronic heat pumps and water-cooled unitary air-conditioners shall have a two-position automatic valve interlocked to shut off water flow when the compressor is off.

Exception: Units employing water economizers. [ASHRAE 90.1:6.5.4.5.1]
Hydronic heat pumps and water-cooled unitary air-conditioners having a total pump system power exceeding 5 hp (3.7 kW) shall have controls, devices, or both (such as variable speed control) that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. [ASHRAE 90.1:6.5.4.5.2]
Chilled-water and condenser-water piping shall be designed such that the design flow rate in a pipe segment does not exceed the values listed in Table E 503.5.7.5 for the appropriate total annual hours of operation. Pipe size selections for systems that operate under variable flow conditions, such as modulating two-way control valves at coils, and that contain variable speed pump motors shall be permitted to be made from the "Variable Flow/Variable Speed" columns. All others shall be made from the "Other" columns.

Exceptions:
  1. Design flow rates exceeding the values in Table E 503.5.7.5 shall be permitted in specific sections of pipe where the pipe is not in the critical circuit at design conditions and is not predicted to be in the critical circuit during 30 percent or more of operating hours.
  2. Piping systems that have not more than the total pressure drop than the same system constructed with standard weight steel pipe with piping and fittings sized in accordance with Table E 503.5.7.5. [ASHRAE 90.1:6.5.4.6]


TABLE E 503.5.7.5
PIPING SYSTEM DESIGN MAXIMUM FLOW RATE (gallons per minute)
[ASHRAE 90.1: TABLE 6.5.4.6]
OPERATING HOURS/YEAR ≤ 2000 HOURS/YEAR > 2000 AND ≤ 4400 HOURS/YEAR > 44000 HOURS/YEAR
NOMINAL PIPE SIZE,
(inches)
OTHER VARIABLE FLOW/
VARIABLE SPEED
OTHER VARIABLE FLOW/
VARIABLE SPEED
OTHER VARIABLE FLOW/
VARIABLE SPEED
212 120 180 85 130 68 110
3 180 270 140 210 110 170
4 350 530 260 400 210 320
5 410 620 310 470 250 370
6 740 1100 570 860 440 680
8 1200 1800 900 1400 700 1100
10 1800 2700 1300 2000 1000 1600
12 2500 3800 1900 2900 1500 23000
Maximum
velocity for pipes over
14-24 inches in size
8.5 ft/s ft/s 6.5 ft/s 9.5 ft/s 5.0 ft/s 7.5 ft/s
For SI units: 1 gallon per minute = 0.06 L/s, 1 foot per second = 0.3048 m/s, 1 inch = 25.4 mm
Section E 503.5.8 through Section E 503.5.9 apply to heat rejection equipment used in comfort cooling systems such as air-cooled condensers, dry coolers, open-circuit cooling towers, closed-circuit cooling towers, and evaporative condensers.

Exception: Heat rejection devices whose energy usage is included in the equipment efficiency ratings listed in Table E 503.7.1(1) through Table E 503.7.1(4). [ASHRAE 90.1:6.5.5.1]
Fans powered by a motor of 7.5 hp (5.59 kW) or larger shall have the capability to operate at two-thirds full speed or less, and shall have controls that automatically change the fan speed to control the leaving fluid temperature or condensing temperature or pressure of the heat rejection device.

Exceptions:
  1. Condenser fans serving multiple refrigerant circuits.
  2. Condenser fans serving flooded condensers.
  3. Installations located in climate zone 1 and zone 2. [ASHRAE 90.1:6.5.5.2.1]
Centrifugal fan open-circuit cooling towers with a combined rated capacity of 1100 gallons per minute (gpm) (69.39 L/s) or greater at 95°F (35°C) condenser water return, 85°F (29°C) condenser water supply, and 75°F (24°C) outdoor air wet-bulb temperature shall comply with the energy efficiency requirement for axial fan open-circuit cooling towers in accordance with Table E 503.7.1(7).

Exception: Centrifugal open-circuit cooling towers that are ducted (inlet or discharge) or require external sound attenuation. [ASHRAE 90.1:6.5.5.3]
A fan system shall have an energy recovery system where the system's supply airflow rate exceeds the value listed in Table E 503.5.10(1) and Table E 503.5.10(2), based on the climate zone and percentage of outdoor airflow rate at design conditions. Table E 503.5.10(1) shall be used for all ventilation systems that operate less than 8000 hours per year and Table E 503.5.10(2) shall be used for all ventilation systems that operate 8000 or more hours per year.

     Energy recovery systems required by this section shall have 50 percent or more energy recovery effectiveness. Fifty percent energy recovery effectiveness shall be the change in the enthalpy of the outdoor air supply equal to 50 percent of the difference between the outdoor air and return air enthalpies at design conditions. Provision shall be provided to bypass or control the energy recovery system to permit air economizer operation in accordance with Section E 503.5.1.

Exceptions:
  1. Laboratory systems that are in accordance with Section E 503.5.11.3.
  2. Systems serving spaces that are not cooled and that are heated to less than 60°F (16°C).
  3. Systems exhausting toxic, flammable, paint, corrosive fumes, or dust.
  4. Commercial kitchen hoods used for collecting and removing grease vapors and smoke.
  5. Where more than 60 percent of the outdoor air heating energy is provided from site-recovered or site-solar energy.
  6. Heating energy recovery in climate zones 1 and 2.
  7. Cooling energy recovery in climate zones 3c, 4c, 5b, 5c, 6b, 7, and 8.
  8. Where the largest exhaust source of air exhausted at a single location at the building exterior is less than 75 percent of the design outdoor airflow rate.
  9. Systems requiring dehumidification that employ energy recovery in series with the cooling coil.
  10. Systems expected to operate less than 20 hours per week at the outdoor air percentage in accordance with Table E 503.5.10(1). [ASHRAE 90.1:6.5.6.1]
TABLE E 503.5.10(1)
EXHAUST AIR ENERGY RECOVERY REQUIREMENTS FOR VENTILATION
SYSTEMS OPERATING LESS THAN 8000 HOURS PER YEAR*
[ASHRAE 90.1:TABLE 6.5.6.1-1]
ZONE PERCENT OUTDOOR AIR AT FULL DESIGN AIRFLOW RATE
≥ 10% and
< 20%
≥ 20% and
< 30%
≥ 30% and
< 40%
≥ 40% and
< 50%
≥ 50% and
< 60%
≥ 60% and
< 70%
≥ 70% and
< 80%
≥ 80%
DESIGN SUPPLY FAN AIRFLOW RATE (cubic feet per minute)
3B, 3C, 4B, 4C,
5B
NR NR NR NR NR NR NR NR
1B, 2B, 5C NR NR NR NR ≥26000 ≥12000 ≥5000 ≥4000
6B ≥28000 ≥26500 ≥11000 ≥5500 ≥4500 ≥3500 ≥2500 ≥1500
1A, 2A, 3A,
4A, 5A, 6A
≥26000 ≥16000 ≥5500 ≥4500 ≥3500 ≥2000 ≥1000 >0
7, 8 ≥4500 ≥4000 ≥2500 ≥1000 >0 >0 >0 >0
For SI units: 1 cubic foot per minute = 0.00047 m3/s
* NR = Not Required



TABLE E 503.5.10(2)
EXHAUST AIR ENERGY RECOVERY REQUIREMENTS FOR VENTILATION SYSTEMS OPERATING NOT LESS THAN 8000 HOURS PER YEAR*
[ASHRAE 90.1:TABLE 6.5.6.1-2]
ZONE PERCENT OUTDOOR AIR AT FULL DESIGN AIRFLOW RATE
≥ 10% and
< 20%
≥ 20% and
< 30%
≥ 30% and
< 40%
≥ 40% and
< 50%
≥ 50% and
< 60%
≥ 60% and
< 70%
≥ 70% and
< 80%
≥ 80%
DESIGN SUPPLY FAN AIRFLOW RATE (cubic feet per minute)
3C NR NR NR NR NR NR NR NR
1B, 2B, 3B, 4C,
5C
NR ≥19500 ≥9000 ≥5000 ≥4000 ≥3000 ≥1500 >0
1A, 2A, 3A,
4B, 5B
≥2500 ≥2000 ≥1000 ≥500 >0 >0 >0 >0
4A, 5A, 6A,
6B, 7
>0 >0 >0 >0 >0 >0 >0 >0
For SI units: 1 cubic foot per minute = 0.00047 m3/s
* NR = Not Required
Heat recovery shall comply with Section E 503.5.10.1.1 and Section E 503.5.10.1.2.
Condenser heat recovery systems shall be installed for the heating or preheating of service hot water where the following conditions exist:
  1. The facility operates 24 hours a day.
  2. The total installed heat rejection capacity of the water-cooled system is more than 6000000 Btu/h (1757 kW) ofhcat rejection.
  3. The design service water heating load is more than 1000000 Btu/h (293 kW). [ASHRAE 90.1:6.5.6.2.1]
The required heat recovery system shall have the capacity to provide the smaller of:
  1. Sixty percent of the peak heat rejection load at design conditions.
  2. Preheat of the peak service hot water draw to 85°F (29°C).
Exceptions:
  1. Facilities that employ condenser heat recovery for space heating with a heat recovery design of more than 30 percent of the peak water-cooled condenser load at design conditions.
  2. Facilities that provide 60 percent of their service water heating from site-solar, site-recovered energy, or from other sources. [ASHRAE 90.1:6.5.6.2.2]
Exhaust systems shall comply with Section E 503.5.11.1 through Section E 503.5.11.3.
Replacement air introduced directly into the hood cavity of kitchen exhaust hoods shall not exceed 10 percent of the hood exhaust airflow rate. [ASHRAE 90.1:6.5.7.1.1]
Conditioned supply air delivered to a space with a kitchen hood shall not exceed the greater of the following:
  1. The supply flow required to be in accordance with the space heating or cooling load.
  2. The hood exhaust flow minus the available transfer air from adjacent spaces. Available transfer air is that portion of outdoor ventilation air not required to satisfy other exhaust needs, such as restrooms, and not required to maintain pressurization of adjacent spaces. [ASHRAE 90.1:6.5.7.1.2]
Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate exceeding 5000 ft3/min (2.3597 m3/s), each hood shall have an exhaust rate in accordance with Table E 503.5.11.2. Where a single hood, or hood section, is installed over appliances with different duty ratings, the maximum allowable flow rate for the hood or hood section shall not exceed the values in Table E 503.5.11.2 for the highest appliance duty rating under the hood or hood section. Refer to ASHRAE 154 for definitions of hood type, appliance duty, and net exhaust flow rate.

Exception: Seventy-five percent or more of the total replacement air is transfer air that would otherwise be exhausted. [ASHRAE 90.1:6.5.7.1.3]

TABLE E 503.5.11.2
MAXIMUM NET EXHAUST FLOW RATE, CFM PER LINEAR FOOT OF HOOD LENGTH
[ASHRAE 90.1:TABLE 6.5.7.1.3]
TYPE OF HOOD LIGHT DUTY
EQUIPMENT
MEDIUM DUTY
EQUIPMENT
HEAVY DUTY
EQUIPMENT
EXTRA HEAVY DUTY
EQUIPMENT
Wall-mounted canopy 140 210 280 385
Single island 280 350 420 490
Double island (per side) 175 210 280 385
Eyebrow 175 175 Not allowed Not allowed
Backshelf/Pass-over 210 210 280 Not allowed
For SI units: 1 foot = 304.8 mm, 1 cubic foot per minute = 0.00047 m3/s
Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate more than 5000 ft3/min (2.3597 m3/s), then one of the following shall be provided:
  1. Fifty percent or more of replacement air is transfer air that would otherwise be exhausted.
  2. Demand ventilation system(s) provide 75 percent or more of the exhaust air. Such systems shall be capable of providing 50 percent or more reduction in exhaust and replacement air system airflow rates, including controls necessary to modulate airflow in response to appliance operation and to maintain full capture and containment of smoke, effluent, and combustion products during cooking and idle.
  3. Listed energy recovery devices with a sensible heat recovery effectiveness of 40 percent or more on 50 percent or more of the total exhaust airflow. [ASHRAE 90.1:6.5.7.1.4]
An approved field test method shall be used to evaluate design air flow rates and demonstrate proper capture and containment performance of installed commercial kitchen exhaust systems. Where demand ventilation systems are utilized to be in accordance with Section E 503.5.11.2.1, additional performance testing shall be provided to demonstrate proper capture and containment at minimum airflow. [ASHRAE 90.1:6.5.7.1.5]
Buildings with laboratory exhaust systems having a total exhaust rate of more than 5000 W/min (2.3597 m3/s) shall include not less than one of the following features:
  1. VAV laboratory exhaust and room supply systems capable of reducing exhaust airflow rates, makeup airflow rates, or both incorporate a heat recovery system to precondition makeup air from laboratory exhaust and shall be in accordance with the following:

    A+B•(E/M) ≥ 50% (Equation E 503.5.11.3)
    Where:
    A = Percentage that the exhaust and
    makeup airflow rates are capable of
    being reduced from design conditions.
    B = Percentage sensible recovery
    effectiveness.
    E = Exhaust airflow rate through the heat
    recovery device at design conditions.
    M = Makeup airflow rate of the system at
    design conditions.
  2. VAV laboratory exhaust and room supply systems required to have minimum circulation rates to be in accordance with the codes or standards shall be capable of reducing zone exhaust and makeup airflow rates to the regulated minimum circulation values, or the minimum required to maintain pressurization relationship requirements. Nonregulated zones shall be capable of reducing exhaust and makeup airflow rates to 50 percent of the zone design values, or the minimum required to maintain pressurization relationship requirements.
  3. Direct makeup (auxiliary) air supply of 75 percent or more of the exhaust airflow rate, heated not more than 2°F (1°C) below room setpoint, cooled to not less than 3°F (2°C) above room setpoint, no humidification is added, and no simultaneous heating and cooling are used for dehumidification control. [ASHRAE 90.1:6.5.7.2]
Radiant heating shall be used when heating is required for unenclosed spaces.

Exception: Loading docks equipped with air curtains. [ASHRAE 90.1:6.5.8.1]
Radiant heating systems that are used as primary or supplemental enclosed space heating shall be in accordance with this appendix, including, but not limited to, the following:
  1. Radiant hydronic ceiling or floor panels (used for heating or cooling).
  2. Combination or hybrid systems incorporating radiant heating (or cooling) panels.
  3. Radiant heating (or cooling) panels used in conjunction with other systems such as VAV or thermal storage systems. [ASHRAE 90.1:6.5.8.2]
Cooling systems shall not use hot gas bypass or other evaporator pressure control systems unless the system is designed with multiple steps of unloading or continuous capacity modulation. The capacity of the hot gas bypass shall be limited as indicated in Table E 503.5.13 for VAV units and single-zone VAV units. Hot-gas bypass shall not be used on constant-volume units. [ASHRAE 90.1:6.5.9]

TABLE E 503.5.13
HOT GAS BYPASS LIMITATION
[ASHRAE 90.1:TABLE 6.5.9]
RATED CAPACITY MAXIMUM HOT GAS BYPASS
(percent of total capacity)
≤ 240000 Btu/h 15%
> 240000 Btu/h 10%
For SI units: 1000 British thermal units per hour = 0.293 kW
Conditioned spaces with doors, including doors with more than one-half glass, opening to the outdoors shall be provided with controls that when any such door is open, the following shall occur:
  1. Disable mechanical heating or reset the heating setpoint to 55°F (13°C) or lower within five minutes of the door opening.
  2. Disable mechanical cooling or reset the cooling setpoint to 90°F (32°C) or more within five minutes of the door opening. Mechanical cooling shall be permitted to remain enabled where outdoor air temperature is less than the space temperature.
Exceptions:
  1. Building entries with automatic closing devices.
  2. Any space without a thermostat.
  3. Alterations to existing buildings.
  4. Loading docks. [ASHRAE 90.1:6.5.10]
The Authority Having Jurisdiction shall require submittal of compliance documentation and supplemental information in accordance with Section E 503.6.1 through Section E 503.6.3.
Compliance documents shall show the pertinent data and features of the building, equipment, and systems in sufficient detail to permit a determination of compliance by the building official and to indicate compliance with the requirements of this appendix. [ASHRAE 90.1:4.2.2.1]
Supplemental information necessary to verify compliance with this appendix, such as calculations, worksheets, compliance forms, vendor literature, or other data, shall be made available where required by the Authority Having Jurisdiction. [ASHRAE 90.1:4.2.2.2]
Operating and maintenance information shall be provided to the building owner. This information shall include, but not be limited to, the information specified in Section E 503.6.3.1, Section E 503.6.3.2, and Section E 503.6.5.2. [ASHRAE 90.1:4.2.2.3]
Construction documents shall require that an operating manual and maintenance manual be provided to the building owner. The manuals shall include, at a minimum, the following:
  1. Submittal data stating equipment rating and selected options for each piece of equipment requiring maintenance.
  2. Operation manuals and maintenance manuals for each piece of equipment requiring maintenance. Required routine maintenance actions shall be clearly identified.
  3. Names and addresses of not less than one qualified service agency.
  4. A complete narrative of how each system is intended to operate.
    The Authority Having Jurisdiction shall only check to ensure that the construction documents required are provided to the owner, and shall not expect copies of any of the materials. [ASHRAE 90.1:8.7.2]
Construction documents shall include an operating and maintenance manual for that all lighting equipment and lighting controls, and a copy shall be provided to the building owner or the designated representative of the building owner within 90 days after the date of system acceptance. These manuals shall include, at a minimum, the following:
  1. Submittal data indicating all selected options for each piece of lighting equipment, including but not limited to lamps, ballasts, drivers, and lighting controls.
  2. Operation and maintenance manuals for each piece of lighting equipment and lighting controls with routine maintenance clearly identified including, as a minimum, a recommended relamping or cleaning program and a schedule for inspecting and recalibrating all lighting controls.
  3. A complete narrative of how each lighting control system is intended to operate including recommended settings. [ASHRAE 90.1:9.7.2.2]
Materials and equipment shall be labeled in a manner that will allow for determination of their compliance with the applicable provisions of this appendix. [ASHRAE 90.1:4.2.3]
Section E 503.6.5.1 through Section E 503.6.5.4.1 are mandatory provisions and are necessary to comply with this appendix. [ASHRAE 90.1:6.7.2]
Construction documents shall require that, within 90 days after the date of system acceptance, record drawings of the actual installation be provided to the building owner or the designated representative of the building owner. Record drawings shall include, as a minimum, the location and performance data on each piece of equipment, general configuration of duct and pipe distribution system including sizes, and the terminal air or water design flow rates. [ASHRAE 90.1:6.7.2.1]
Construction documents shall require that an operating manual and a maintenance manual be provided to the building owner or the designated representative of the building owner within 90 days after the date of system acceptance. These manuals shall be in accordance with industry-accepted standards and shall include, at a minimum, the following:
  1. Submittal data stating equipment size and selected options for each piece of equipment requiring maintenance.
  2. Operation manuals and maintenance manuals for each piece of equipment and system requiring maintenance, except equipment not furnished as part of the project. Required routine maintenance actions shall be clearly identified.
  3. Names and addresses of not less than one service agency.
  4. HVAC controls system maintenance and calibration infom1ation, including wiring diagrams, schematics, and control sequence descriptions. Desired or field-determined setpoints shall be permanently recorded on control drawings at control devices or, for digital control systems, in programming comments.
  5. A complete narrative of how each system is intended to operate, including suggested setpoints. [ASHRAE 90.1:6.7.2.2]
Construction documents shall require that HVAC systems be balanced in accordance with generally accepted engineering standards. Construction documents shall require that a written balance report be provided to the building owner or the designated representative of the building owner for HVAC systems serving zones with a total conditioned area exceeding 5000 square feet (464.52 m2). [ASHRAE 90.1:6.7.2.3.1]
Air systems shall be balanced in a manner to first minimize throttling losses. Then, for fans with fan system power greater than 1 hp (0.7 kW), fan speed shall be adjusted to meet design flow conditions. [ASHRAE 90.1:6.7.2.3.2]
Hydronic systems shall be proportionately balanced in a manner to first minimize throttling losses; then the pump impeller shall be trimmed or pump speed shall be adjusted to meet design flow conditions.

Exceptions: Impellers need not be trimmed nor pump speed adjusted.
  1. For pumps with pump motors of 10 hp (7.5 kW) or less.
  2. Where throttling results is not greater than 5 percent of the nameplate horsepower draw, or 3 hp (2.2 kW), whichever is greater, above that required where the impeller was trimmed. [ASHRAE 90.1:6.7.2.3.3]
HVAC control systems shall be tested to ensure that control elements are calibrated, adjusted, and in proper working condition. For projects larger than 50000 square feet (4645.15 m2) conditioned area, except warehouses and semiheated spaces, detailed instructions for commissioning HVAC systems shall be provided by the designer in plans and specifications. [ASHRAE 90.1:6.7.2.4]
Commissioning shall be performed for HVAC systems in accordance with Level 1, Basic Commissioning of the SMACNA HVAC Systems Commissioning Manual. (See Section E 801.0 for additional information on HVAC system commissioning)
The minimum efficiency requirements for equipment shall comply with Section E 503.7.1, duct insulation shall comply with Section E 503.7.2, and pipe insulation shall comply with Section E 503.7.3.
The minimum efficiency requirements for equipment shall comply with Table E 503.7.1(1) through Table E 503.7.1(13).

TABLE E 503.7.1(1)
ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS MINIMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1:TABLE 6.8.1-1]
For SI units: 1000 British thermal units per hour = 0.293 kW

Notes:
1   ASHRAE 90.1 contains a complete specification of the referenced test procedure including the referenced year version of the test procedure.
2   Single-phase, air-cooled air conditioners less than 65000 Btu/h (19 kW) are regulated by NAECA. SEER values shall be those set by NAECA.



TABLE E 503.7.1(2)
ELECTRICAllY OPERATED UNITARY AND APPLIED HEAT PUMPS MINiMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1:TABLE 6.8.1-2]
For SI units: 1000 British thermal units per hour = 0.293 kW, °C - (°F-32)/1.8

Notes:
1   ASHRAE 90.1 contains a complete specification of the referenced test procedure including the referenced year version of the test procedure.
2   Single-phase, air-cooled air conditioners less than 65000 Btu/h (19 kW) are regulated by NAECA. SEER values shall be those set by NAECA.



TABLE E 503.7.1(3)
WATER CHILLING PACKAGES - EFFICIENCY REQUIREIVIENTS1,2,5
[ASHRAE 90.1:TABLE 6.8.1-3]
For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW

Notes:
1   The requirement for centrifugal chiller, shall be adjusted for nonstandard rating conditions in accordance with Section E 503.4.1 and are only applicable for the range of conditions listed there. The requirements for air-cooled, water-cooled positive displacement and absorption chillers are at standard rating conditions defined in the reference test procedure.
2   Both the full-load and IPLV requirements shall be met or exceeded to comply with this appendix. When there is a Path B, compliance shall be permitted to be either Path A or Path B for any application.
3   ASHRAE 90.1 contains a complete specification of the referenced test procedure including the referenced year version of the test procedure.
4   NA means the requirements are not applicable for Path B, and only Path A shall be permitted to be used.
5   FL shall be the full-load performance requirements, and IPLV shall be for the part-load performance requirements.



TABLE E 503.7.1(4)
ELECTRICALLY OPERATED PACKAGED TERMINAL AIR CONDITIONERS, PACKAGED TERMINAL, HEAT PUMPS, SINGLE-PACKED VERTICAL AIR CONDITIONERS, SINGLE-PACKAGE VERTICAL HEAT PUMPS, ROOM AIR CONDITIONERS, AND ROOM AIR CONDITIONER HEAT PUMPS - MINIMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1:TABLE 6.8.1-4]
For SI units: 1000 British thermal units per hour = 0.293 kW, °C = (°F-32)/1.8

Notes:
1   ASHRAE 90.1 contains a complete specification of the referenced test procedure including the referenced year version of the test procedure.
2   Nonstandard size units shall be factory labeled as follows: "MANUFACTURED FOR NONSTANDARD SIZE APPLICATIONS ONLY; NOT TO BE INSTALLED IN NEW STANDARD PROJECTS." Nonstandard size efficiencies apply only to units being installed in existing sleeves having an external wall opening of less than 16 inch (406 mm) high or less than 42 inch (1067 mm) wide and having a cross-sectional area less than 670 square inches (0.432 m2).
3   "Cap" shall mean the rated cooling capacity of the product in Btu/h (kW). Where the unit's capacity is less than 7000 Btu/h 12.05 kW), use 7000 Btu/h (2.05 kW) in the calculation. Where the unit's capacity is more than 15000 Btu/h (4.4 kW), use 15000 Btu/h 14.4 kW) in the calculation.



TABLE E 503.7.1(5)
WARM AIR FURNACES AND COMBINATION WARM AIR FURNACES/AIR-CONDITIONING UNITS, WARM AIR DUCT FURNACES AND UNIT HEATERS
[ASHRAE 90.1: TABLE 6.8.1-5]
For SI units: 1000 British thermal units per hour = 0.293 kW

Notes:
1   ASHRAE 90.1 contains a complete specification of the referenced test procedure including the referenced year version of the test procedure.
2   Combination units not covered by NAECA [three-phase power or cooling capacity of 65000 Btu/h (19 kW)] or more shall be permitted to comply with either rating.
3   Multiple firing rate units shall be at the maximum firing rate.
4   Et = thermal efficiency. Units shall include an interrupted or intermittent ignition device (IID), have jacket losses not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.
5   Ec= combustion efficiency (100 percent less flue losses). See test procedure for detailed discussion.
6   As of August 8, 2008, in accordance with the Energy Policy Act of 2005, units shall also include an interrupted or intermittent ignition device (IID) and have either power venting or an auTomatic flue damper.



TABLE E 503.7.1(6)
GAS AND OIL-FIRED BOILERS, MINIMUM EFFICIENCY REQUIREMENTS2, 3
[ASHRAE 90.1: TABLE 6.8.1-6]
For SI units: 1000 British thermal units per hour = 0.293 kW

Notes:
1   These requirements apply to boilers with rated input of 8000000 Btu/h (2343 kW) or less that are not packaged boilers and to all packaged boilers. Minimum efficiency requirements for boilers cover all capacities of packaged boilers.
2   Ec= combustion efficiency (100 percent less flue losses). See reference document for detailed information.
3   Et = thermal efficiency. See reference document for detailed information.  
4   Maximum capacity - minimum and maximum ratings as provided for and allowed by the unit's controls.
5   Includes oil-tired (residual).
6   Boilers shall not be equipped with a constant burning pilot light.
7   A boiler not equipped with a tankless domestic water heating coil shall be equipped with an automatic means for adjusting the temperature of the water such that an incremental change in inferred heat load produces a corresponding incremental change in the temperature of the water supplied.



TABLE E 503.7.1(7)
PERFORMANCE REQUIREMENTS FOR HEAT REJECTION EQUIPMENTB
[ASHRAE 90.1: TABLE 6.8.1-7]
For SI units: °C = (°F-32)/1.8, 1 gallon per minute per horsepower = 0.085 [(L/s)/kW], 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW

Notes:
1   For purposes of this table, open-circuit cooling tower performance shall be defined as the water flow rating ofthe tower at the thermal rating condition listed in Table E 503.7.1(7) divided by the fan motor nameplate rating.
2   For purposes of this table, closed-circuit cooling tower performance shall be defined as the process water flow rating of the tower at the thermal rating condition listed in Table E 503.7.1(7) divided by the sum of the fan motor nameplate power and the integral spray pump motor nameplate power.
3   For purposes of this table, air-cooled condenser performance shall be defined as the heat rejected from the refrigerant divided by the fan motor nameplate power.
4   ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
5   The efficiencies and test procedures for both open- and closed-circuit cooling towers shall not be applicable to hybrid cooling towers that contain a combination of separate wet and dry heat exchange sections. The certification requirements shall not apply to field-erected cooling towers.
6   Cooling towers shall comply with the minimum efficiency listed in the table for that specific type of tower with the capacity effect of project-specific accessories, options, or both included in the capacity of the cooling tower.
7   For purposes of this table, evaporative condenser performance shall be defined as the heat rejected at the specified rating condition in the table, divided by the sum of the fan motor nameplate power and the integral spray pump nameplate power.
8   Requirements for evaporative condensers are listed with ammonia (R-717) and R-507A as test f1uids in the table. Evaporative condensers intended for use with halocarbon refrigerants other than R-507A shall be in accordance with the minimum efficiency requirements listed above with R-507 A as the test fluid.



TABLE E 503.7.1(8)
HEAT TRANSFER EQUIPMENT
[ASHRAE 90.1:TABLE 6.8.1-8]
Notes:
1   NR = No Requirement
2   ASHRAE 90.1 contains complete specification of the referenced test procedure, including the referenced year version of the test procedure.



TABLE E 503.7.1(9)
ELECTRICALLY OPERATED VARIABLE-REFRIGERANT-FlOW AIR CONDITIONERS-MINIMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1:TABLE 6.8.1-9]
For SI units: 1000 British thermal units per hour = 0.293 kW.



TABLE E 503.7.1(10)
ELECTRICALLY OPERATED VARIABLE REFRIGERANT-FLOW AIR-TO-AIR AND APPLIED HEAT PUMPS MINIMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1: TABLE 6.8.1-10]
For SI units: 1000 British thermal units per hour = 0.293 kW, °C=(°F-32)/1.8



TABLE E 503.7.1(11)
AIR CONDITIONERS AND CONDENSING UNITS SERVING COMPUTER ROOMS
[ASHRAE 90.1:TABLE 6.8.1-11]
For SI units: 1000 British thermal units per hour = 0.293 kW

Notes:
1   Net sensible cooling capacity: The total gross cooling capacity minus the latent cooling, minus the energy to the air movement system (total gross - latent - fan power).
2   Sensible coefficient of performance (SCOP-127): A ratio calculated by dividing the net sensible cooling capacity in watts by the total power input in watts (excluding reheaters and humidifiers) at conditions in accordance with ASHRAE 127. The net sensible cooling capacity shall be the gross sensible capacity minus the energy dissipated into the cooled space by the fan system.



TABLE E 503.7.1(12)
COMMERCIAL REFRIGERATOR AND FREEZER
[ASHRAE 90.1: TABLE 6.8.1-12]
For SI units: 1000 British thermal Units per hour per day = 0.293 kW/day
*   V = the chiller or frozen compartment volume (ft3) in accordance with the home appliance manufacturers standard.



TABLE E 503.7.1(13)
COMMERCIAL REFRIGERATION-MINIMUM EFFICIENCY REQUIREMENTS
[ASHRAE 90.1: TABLE 6.8.1-13]
For SI units: 1000 British thermal units per hour per day = 0.293 kW /day, °C = (°F-32)/1.8

Notes:
1   Equipment class designations consist of a combination [in sequential order separated by periods (AAA).(BB).(C)] of the following:
  1. (AAA)- An equipment family code (VOP = vertical open, SVO = semivertical open, HZO = horizontal open, VCT = vertical transparent doors, VCS = vertical solid doors, HCT = horizontal transparent doors, HCS = horizontal solid doors, and SOC = service over counter).
  2. (BB)- An operating mode code (RC = remote condensing and SC = self contained).
  3. (C)- A rating temperature code (M = medium temperature [38°F], L = low temperature [0°F], or I = ice cream temperature [15°F]). For example, "VOP.RC.M" refers to the "vertical open, remote condensing, medium temperature" equipment class.
2   V is the volume of the case (ft) as measured in accordance with AHRI 1200.
3   TDA is the total display area of the case (ft) as measured in accordance with AHRI 1200.
Duct insulation shall comply with Table E 503.7.2(1) through Table E 503.7.2(2).


TABLE E 503.7.2(1)
MINIMUM DUCT INSULATION R-VALUE1 FOR COOLING AND HEATING ONLY SUPPLY DUCTS AND RETURN DUCTS
[ASHRAE 90.1: TABLE 6.8.2-1]
CLIMATE ZONE DUCT LOCATION
EXTERIOR VENTILATED
ATTIC
UNVENTED
ATTIC ABOVE
INSULATED
CEILING
UNVENTED
ATTIC WITH
ROOF
INSULATION1
UNCONDITIONED
SPACE2
INDIRECTLY
CONDITIONED
SPACE3
BURIED
HEATING ONLY DUCTS
1, 2 none none none none none none none
3 R-3.5 none none none none none none
4 R-3.5 none none none none none R-3.5
5 R-6 R-3.5 none none none none R-3.5
6 R-6 R-6 R-3.5 none none none R-3.5
7 R-8 R-6 R-6 none R-3.5 none R-6
8 R-8 R-6 R-6 none R-6 none R-3.5
COOLING ONLY DUCTS
1 R-6 R-6 R-8 R-3.5 R-3.5 none R-3.5
2 R-6 R-6 R-6 R-3.5 R-3.5 none R-3.5
3 R-6 R-6 R-6 R-3.5 R-1.9 none none
4 R-3.5 R-3.5 R-6 R-1.9 R-1.9 none none
5, 6 R-3.5 R-1.9 R-3.5 R-1.9 R-1.9 none none
7, 8 R-1.9 R-1.9 R-1.9 R-1.9 R-1.9 none none
RETURN DUCTS
1 to 8 R-3.5 R-3.5 R-3.5 none none none none
Notes:
1   Insulation R-values, measured in [°F•h•ft2/(Btu•in)] [(m•K)/W], are for the insulation as installed and do not include film resistance. The required minimum thicknesses do not consider water vapor transmission and possible surface condensation. Where exterior walls are used as plenum walls, wall insulation shall be in accordance with the most restrictive condition of Section E 503.4.7.2 or ASHRAE 90.1. Insulation resistance measured on a horizontal plane in accordance with ASTM C518 at a mean temperature of 75°F (24°C) at the installed thickness.
2   Includes crawlspaces, both ventilated and nonventilated.
3   Includes return air plenum, with or without exposed roofs above.


TABLE E 503.7.2(2)
MINIMUM DUCT INSULATION R-VALUE1 FOR COMBINED HEATING AND COOLING SUPPLY DUCTS AND RETURN DUCTS
[ASHRAE 90.1: TABLE 6.8.2-2]
CLIMATE ZONE DUCT LOCATION
EXTERIOR VENTILATED
ATTIC
UNVENTED
ATTIC ABOVE
INSULATED
CEILING
UNVENTED
ATTIC WITH
ROOF
INSULATION1
UNCONDITIONED
SPACE2
INDIRECTLY
CONDITIONED
SPACE3
BURIED
SUPPLY DUCTS
1 R-6 R-6 R-8 R-3.5 R-3.5 none R-3.5
2 R-6 R-6 R-6 R-3.5 R-3.5 none R-3.5
3 R-6 R-6 R-6 R-3.5 R-3.5 none R-3.5
4 R-6 R-6 R-6 R-3.5 R-3.5 none R-3.5
5 R-6 R-6 R-6 R-1.9 R-3.5 none R-3.5
6 R-8 R-6 R-6 R-1.9 R-3.5 none R-3.5
7 R-8 R-6 R-6 R-1.9 R-3.5 none R-3.5
8 R-8 R-8 R-8 R-1.9 R-6 none R-6
RETURN DUCTS
1 to 8 R-3.5 R-3.5 R-3.5 none none none none
Notes:
1   Insulation R-values, measured in [°F•h•ft2/(Btu•in)] [(m•K)/W], are for the insulation as installed and do not include film resistance. The required minimum thicknesses do not consider water vapor transmission and possible surface condensation. Where exterior walls are used as plenum walls, wall insulation shall be in accordance with the most restrictive condition of Section E 503.4.7.2 or ASHRAE 90.1. Insulation resistance measured on a horizontal plane in accordance with ASTM C518 at a mean temperature of 75°F (24°C) at the installed thickness.
2   Includes crawlspaces, both ventilated and nonventilated.
3   Includes return air plenum, with or without exposed roofs above.
Pipe insulation shall comply with Table E 503.7.3(1) through Table E 503.7.3(2).

TABLE E 503.7.3(1)
MINIMUM PIPE INSULATION THICKNESS FOR HEATING AND HOT WATER SYSTEMS1 2, 3, 4, 5 (STEAM, STEAM CONDENSATE, HOT WATER HEATING, AND DOMESTIC WATER SYSTEMS)
[ASHRAE 90.1: TABLE 6.8.3-1]
FLUID OPERATING
TEMPERATURE RANGE
(°F) AND USAGE
INSULATION CONDUCTIVITY NOMINAL PIPE SIZE OR TUBE SIZE (inches)
CONDUCTIVITY
Btu•inch/(h•ft2•°F)
MEAN RATING
TEMPERATURE
°F
<1 1 to < 1-1/2 1-1/2 to < 4 4 to < 8 ≥ 8
INSULATI0N THICKNESS (inches)
> 350 0.32 - 0.34 250 4.5 5.0 5.0 5.0 5.0
251 - 350 0.29 - 0.32 200 3.0 4.0 4.5 4.5 4.5
201 -250 0.27 - 0.30 150 2.5 2.5 2.5 3.0 3.0
141 - 200 0.25 -0.29 125 1.5 1.5 2.0 2.0 2.0
105-140 0.22 - 0.28 100 1.0 1.0 1.5 1.5 1.5
For SI units: °C = (F-32)/1.8, 1 inch = 25 mm, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/m•K )]

Notes:
1   For insulation outside the stated conductivity range, the minimum thickness (T) shall be determined as follows:
T = r{(1 + t/r)K/k - 1}

Where:
T = minimum insulation thickness (inches).
r = actual outside radius of pipe (inches). t = insulation thickness listed in this table for applicable fluid temperature and pipe size.
K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft2•°F)] [W/(m•K)].
k = the upper value of the conductivity range listed in this table for the applicable fluid temperature.

2   These thicknesses shall be based on energy efficiency considerations only. Additional insulation shall be permitted to required relative to safety issues/surface temperature.
3   Piping 112 inches (40 mm) or less and located in partitions within conditioned spaces, reduction of insulation thickness by 1 inch (25.4 mm) shall be permitted before thickness adjustment required in footnote 1, but not a thickness less than 1 inch (25.4 mm).
4   For direct-buried heating and hot water system piping, reduction of insulation thickness by 112 inch (40 mm) shall be permitted before thickness adjustment required in footnote 1, but not a thickness less than 1 inch (25.4 mm).
5   Table E 503.7.3(1) is based on steel pipe. Non-metallic pipes, less than schedule 80 thickness shall use the table values. For other non-metallic pipes having a thermal resistance more than that of steel pipe, reduced insulation thicknesses shall be permitted where documentation is provided showing that the pipe with the proposed insulation has less heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table E 503.7.3(1).


TABLE E 503.7.3(2)
MINIMUM PIPE INSULATION THICKNESS FOR COOLING SYSTEMS (CHILLED WATER, BRINE, AND REFRIGERANT)1, 2, 3, 4
[ASHRAE 90.1: TABLE 6.8.3-2]
FLUID OPERATING
TEMPERATURE RANGE
(°F) AND USAGE
INSULATION CONDUCTIVITY NOMINAL PIPE SIZE OR TUBE SIZE (inches)
CONDUCTIVITY
Btu•inch/(h•ft2•°F)
MEAN RATING
TEMPERATURE
°F
<1 1 to < 1-1/2 1-1/2 to < 4 4 to < 8 > 8
INSULATI0N THICKNESS (inches)
40°F - 60°F 021 - 0.27 75 0.5 0.5 1.0 1.0 1.0
< 40°F 0.20 - 0.26 50 0.5 1.0 1.0 1.0 1.5
For SI units: °C = (F-32)/1.8, 1 inch = 25 mm, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/m•K )]

Notes:
1   For insulation outside the stated conductivity range, the minimum thickness (T) shall be determined as follows:
T = r{(1 + t/r)K/k - 1}

Where:
T = minimum insulation thickness (inches).
r = actual outside radius of pipe (inches).
t = insulation thickness listed in this table for applicable fluid temperature and pipe size.
K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft2•°F)] [W/(m•K)].
k = the upper value of the conductivity range listed in this table for the applicable fluid temperature.
2   These thicknesses shall be based on energy efficiency considerations only. Issues such as water, vapor permeability, or surface condensation require vapor retarders or additional insulation.
3   Insulation shall not be required for direct-buried cooling system piping.
4   Table E 503.7.3(2) is based on steel pipe. Non-metallic pipes less than schedule 80 thickness shall use the table values. For other non-metallic pipes having thermal resistance more than that of steel pipe, reduced insulation thicknesses shall be permitted where documentation is provided showing that the pipe with the proposed insulation has less heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table E 503.7.3(2).
HVAC systems serving heating, cooling, or ventilation needs of a computer room shall be in accordance with Section E 503.1, Section E 1503.4, Section E 503.8.1 or Section E 503.8.2, Section E 503.8.3, Section E 503.6 through Section E 503.6.5.4, and Section E 503.7. [ASHRAE 90.1:6.6.1]
The computer room PUE1 shall be not more than the values listed in Table E 503.8.1. Hourly simulation of the proposed design, for purposes of calculating PUE1, shall be in accordance with ASHRAE 90.1.

Exception: The compliance path shall not be permitted for a proposed computer room design utilizing a combined heat and power system. [ASHRAE 90.1:6.6.1.1]

TABLE E 503.8.1
POWER USAGE EFFECTIVENESS (PUE) MAXIMUM
[ASHRAE 90.1:TABLE 6.6.1]
CLIMATE ZONE PUE*
1A 1.61
2A 1.49
3A 1.41
4A 1.36
5A 1.36
6A 1.34
1B 1.53
2B 1.45
3B 1.42
4B 1.38
5B 1.33
6B 1.33
3C 1.39
4C 1.38
5C 1.36
7 1.32
8 1.30
* PUE0 and PUE1 shall not include energy for battery charging.
The computer room PUE0 shall be not more than the values listed in Table E 503.8.1. The PUE0 shall be the highest value determined at outdoor cooling design temperatures, and shall be limited to systems utilizing electricity for an energy source. The PUE0 shall be calculated for the following conditions:
  1. One hundred percent design IT equipment energy.
  2. Fifty percent design IT equipment energy. [ASHRAE 90.1:6.6.1.2]
Documentation on the following components shall be provided, including a breakdown of energy consumption or demand:
  1. IT equipment
  2. Power distribution losses external to the IT equipment
  3. HVAC systems
  4. Lighting [ASHRAE 90.1:6.6.1.3]
Solar energy systems shall be installed in accordance with the Uniform Solar Energy and Hydronics Code (USEHC).
Geothermal systems that use the earth or body of water as a heat source or sink for heating or cooling shall be in accordance with Section E 505.1.1 through Section E 509.2.
Geothermal systems shall be designed by a registered design professional. The geothermal system design, installation and testing shall be in accordance with CSA C448.
Water source heat pumps used in conjunction with geothermal heat exchangers shall be listed and labeled for use in such systems and shall be designed for the minimum and maximum design water temperature.
Ground source heat pump ground-loop piping and tubing material for water-based systems shall comply with the standards cited in this appendix.
Piping shall be rated for the operating temperature and pressure of the ground source heat pump-loop system. Fittings shall be rated for the temperature and pressure applications and recommended by the manufacturer for installation with the piping material installed. Where used underground, materials shall be approved for burial.
The installation of used pipe, fittings, valves, and other materials shall not be permitted.
Ground source heat pump ground-loop pipe and tubing shall comply with the standards listed in Table E 505.5.

TABLE E 505.5
PLASTIC GROUND SOURCE LOOP PIPING
MATERIAL STANDARD
Chlorinated polyvinyl chloride
(CPVC)
ASTM D2846; ASTM F441;
ASTM F442
Cross-linked polyethylene
(PEX)
ASTM F876; ASTM F877;
CSA 8137.5
Polyethylene/aluminum/poly
ethylene(PE-AL-PE) pressure
pipe
ASTM F1282; CSA B137.9
High Density Polyethylene
(HDPE)
ASTM D2737; ASTM D3035;
ASTM F174; AWWA C901;
CSA B 137.1; CSA C448;
NSF 358-1
Polypropylene (PP) ASTM F2389; CSA B137.11,
NSF 358-2
Polyvinyl chloride (PVC) ASTM D1785; ASTM D2241
Polyethylene Raised Temperature
(PE-RT)
ASTM F2623; ASTM F2769
Fittings for ground source heat pump systems shall be approved for installation with the piping materials to be installed, and shall comply with the standards listed in Table E 505.6.

TABLE E 505.6
GROUND SOURCE LOOP PIPE FITTINGS
MATERIAL STANDARD
Chlorinated polyvinyl chloride (CPVC) ASTM D2846; ASTM F437; ASTM F438; ASTM F439; ASTM F1970; CSA B137.6
Cross-linked polyethylene (PEX) ASTM F877; ASTM F1807; ASTM F1960; ASTM F2080;
ASTM F2159; ASTM F2434; CSA B137.5
Polyethylene/aluminum/poly ethylene
(PE-AL-PE)
ASTM F1282; ASTM F2434; CSA B137.9
High Density Polyethylene (HDPE) ASTM D2683; ASTM D3261; ASTM F1055; CSA B137.1; CSA C448, NSF 358-1
Polypropylene (PP) ASTM F2389; CSA B137.11, NFA 358-2
Polyvinyl chloride (PVC) ASTM D2464; ASTM D2466; ASTM D2467; ASTM F1970; CSA B137.2; CSA B137.3
Polyethylene Raised Temperature (PE-RT) ASTM D3261; ASTM F1807; ASTM F2159; ASTM F2769; CSA B137.1
Joints and connections shall be of an approved type. Joints and connections shall be tight for the pressure of the ground source-loop system. Joints and fittings used underground shall be approved for buried applications.
Joints between various piping materials shall be made with approved transition fittings.
Pipe shall be cut square, reamed, and free of burrs and obstructions. Pipe ends shall have full-bore openings and shall not be undercut. CPVC, PE, and PVC pipe shall be chamfered.
Where required by Section E 506.6 through Section E 506.12.2, the preparation and installation of mechanical and thermoplastic-welded joints shall be in accordance with Section E 506.4 and Section E 506.5.
Mechanical joints shall be installed in accordance with the manufacturer's installation instructions.
Joint surfaces for thermoplastic welded joints shall be cleaned by an approved procedure. Joints shall be welded in accordance with the manufacturer's installation instructions.
Joints between CPVC plastic piping and fittings shall comply with Section E 506.7.1 and Section E 506.7.2.
Threads shall comply with ASME B1.20.1. Schedule 80 or heavier plastic pipe shall be threaded with dies specifically designed for plastic pipe. Thread lubricant, pipe-joint compound or tape shall be applied on the male threads only and shall be approved for application on the piping material.
Solvent cement joints for CPVC pipe and fittings shall be clean from dirt and moisture. Solvent cements in accordance with ASTM F493, requiring the use of a primer, shall be orange in color. The primer shall be colored and be in accordance with ASTM F656. Listed solvent cement in accordance with ASTM F493 that does not require the use of primers, yellow or red in color shall be permitted for pipe and fittings manufactured in accordance with ASTM D2846, 12 of an inch (15 mm) through 2 inches (50 mm) in diameter.
Compression or plastic to metal transition joints between cross-linked polyethylene plastic tubing and fittings shall comply with Section E 506.8.1 and Section E 506.8.2. Mechanical joints shall comply with Section E 506.5.
Where compression-type fittings include inserts and ferrules or o-rings, the fittings shall be installed with the inserts and ferrules or o-rings.
Soldering on the metal portion of the system shall be performed not less than 18 inches (457 mm) from a plastic-to-metal adapter in the same water line.
Joints between polyethylene plastic piping shall comply with Section E 506.9.1 through Section E 506.9.3.
Joints shall be of the socket-fusion, saddle-fusion, or butt-fusion type and joined in accordance with ASTM D2657. Joint surfaces shall be clean and free of moisture. Joint surfaces shall be heated to melt temperatures and joined. The joint shall be undisturbed until cool. Fittings shall be manufactured in accordance with ASTM D2683 or ASTM D3261.
Joints shall be of the electrofusion type. Joint surfaces shall be clean and free of moisture, and scoured to expose virgin resin. Joint surfaces shall be heated to melt temperatures for the period of time specified by the manufacturer. The joint shall be undisturbed until cool. Fittings shall be manufactured in accordance with ASTM F1055.
Joint surfaces shall be clean and free of moisture. Pipe ends shall be chamfered and inserted into the fittings to full depth. Fittings shall be manufactured in accordance with ASTM F1924.
Joints between PP plastic pipe and fittings shall comply with Section E 506.10.1 and Section E 506.10.2.
Heat-fusion joints for polypropylene (PP) pipe and tubing joints shall be installed with socket-type heat-fused polypropylene fittings, electrofusion polypropylene fittings, or by butt fusion. Joint surfaces shall be clean and free from moisture. The joint shall be undisturbed until cool. Joints shall be made in accordance with ASTM F2389.
Mechanical and compression sleeve joints shall be installed in accordance with the manufacturer's installation instructions.
Joints between raised temperature polyethylene tubing and fittings shall comply with Section E 506.11.1 and Section E 506.11.2. Mechanical joints shall comply with Section E 506.5.
Where compression-type fittings include inserts and ferrules or o-rings, the fittings shall be installed without omitting the inserts and ferrules or o-rings.
Solder joints in a metal pipe shall not occur within 18 inches (457 mm) of a transition from such metal pipe to PE-RT pipe.
Joints between PVC plastic pipe and fittings shall comply with Section E 506.12.1 and Section E 506.12.2.
Solvent cement joints for PVC pipe and fittings shall be clean from dirt and moisture. Purple primer in accordance with ASTM F656 shall be applied until the surface of the pipe and fitting is softened. Solvent cement in accordance with ASTM D2564 shall be applied to joint surfaces.
Threads shall comply with ASME B1.20.1. Schedule 80 or heavier plastic pipe shall be threaded with dies specifically designed for plastic pipe. Thread lubricant, pipe-joint compound or tape shall be applied on the male threads only and shall be approved for application on the piping material.
Shutoff valves shall be installed in ground source-loop piping systems in the locations indicated in Section E 507.2 through Section E 507.8.
Shutoff valves shall be installed on the supply and return side of a heat exchanger, except where the heat exchanger is integral with a boiler or is a component of a manufacturer's boiler and heat exchanger packaged unit, and is capable of being isolated from the hydronic system by the supply and return valves.
Shutoff valves shall be installed on the building supply and return of a central utility system.
Shutoff valves shall be installed on the connection to a pressure vessel.
Shutoff valves shall be installed on both sides of a pressure-reducing valve.
Shutoff valves shall be installed on connections to mechanical equipment and appliances. This requirement does not apply to components of a ground source loop system such as pumps, air separators, metering devices, and similar equipment.
Shutoff valves shall be installed at connections to nondiaphragm-type expansion tanks.
A pressure relief valve shall be installed on the low-pressure side of a hydronic piping system that has been reduced in pressure. The relief valve shall be set at the maximum pressure of the system design.
Piping, valves, fittings, and connections shall be installed in accordance with the manufacturer's installation instructions.
Where ground source heat pump ground loop systems have a connection to a potable water supply, the potable water system shall be protected.
Openings for pipe penetrations in walls, floors, and ceilings shall be larger than the penetrating pipe. Openings through concrete or masonry building elements shall be sleeved. The annular space surrounding pipe penetrations shall be protected in accordance with the building code.
A pipe in a ground source heat pump piping system, having an exterior surface temperature exceeding 250°F (121°C), shall have a clearance of not less than 1 inch (25.4 mm) from combustible materials.
A ground source heat pump ground-loop piping system shall not be in direct contact with building materials that cause the piping or fitting material to degrade or corrode, or that interferes with the operation of the system.
Piping shall be installed so as to prevent detrimental strains and stresses in the pipe. Provisions shall be made to protect piping from damage resulting from expansion, contraction, and structural settlement. Piping shall be installed so as to avoid structural stresses or strains within building components.
Piping located in a flood hazard area shall be capable of resisting hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding to the design flood elevation.
Pipe shall be supported in accordance with Section 313.1.
Ground source heat pump ground-loop systems shall be designed so that the flow velocities do not exceed the maximum flow velocity recommended by the pipe and fittings manufacturer. Flow velocities shall be controlled to reduce the possibility of water hammer.
Ground source heat pump ground-loop system piping shall be marked with tape, metal tags, or other methods where it enters a building. The marking shall indicate the following words: "GROUND SOURCE HEAT PUMP-LOOP SYSTEM." The marking shall indicate antifreeze used in the system by name and concentration.
Antifreeze and other materials used in the system shall be chemically compatible with the pipe, tubing, fittings, and mechanical systems.
The transfer fluid shall be compatible with the makeup water supplied to the system.
Before connection header trenches are backfilled, the assembled loop system shall be pressure tested with water at 100 psi (689 kPa) for 15 minutes with no observed leaks. Flow and pressure loss testing shall be performed, and the actual flow rates and pressure drops shall be compared to the calculated design values. Where actual flow rate or pressure drop values differ from calculated design values by more than 10 percent, the cause shall be identified and corrective action taken.
Ground source heat pump ground loop piping to be embedded in concrete shall be pressure tested prior to pouring concrete. During pouring, the pipe shall be maintained at the proposed operating pressure.
The provisions of this section shall establish the means of reducing the quantity of air contaminants that are odorous, irritating, or harmful to the comfort and well-being of a building's installers, occupants, and neighbors.
A direct-vent sealed-combustion gas or sealed wood-burning fireplace, or a sealed wood stove shall be installed. The fireplace shall comply with Section E 602.1.1 and Section E 602.1.2.
Masonry and factory-built fireplaces located in conditioned spaces shall be in accordance with Section E 602.1.1.1 through Section E 602.1.1.3.
Closeable metal or glass doors covering the entire opening of the firebox shall be installed.
A combustion air intake to draw air from the outside of the building directly into the firebox, which is an area of not less than 6 square inches (0.004 m2) and is equipped with a readily accessible, operable, and tight-fitting damper or combustion-air control device.
The flue damper shall have a readily accessible control.

Exception: Where a gas log, log lighter, or decorative gas appliance is installed in a fireplace, the flue damper shall be blocked open where required by this code or the manufacturer's installation instructions.
Continuous burning pilot lights and the use of indoor air for cooling a firebox jacket, where the indoor air is vented to the outside of the building, are prohibited.
Indoor air quality of a building shall be maintained in accordance with Section E 603.1.1 through Section E 603.1.3.
Temporary ventilation during construction shall be provided in accordance with the following:
  1. Ventilation during construction shall be achieved through openings in the building shell using fans to produce not less than three air changes per hour.
  2. During dust-producing operations, the supply and return HVAC system openings shall be protected from dust in accordance with Section E 603.1.3.
  3. Where the building is occupied during demolition or construction, ventilation shall be provided in accordance with the Control Measures of the SMACNA IAQ Guidelines for Occupied Buildings Under Construction.
  4. The permanent HVAC system shall not be used during construction to condition and ventilate the building within the required temperature range for material and equipment installation. Where required, a supplemental HVAC system shall be used during construction, return air shall be equipped with filters with a minimum efficiency reporting value (MERV) of 8, in accordance with ASHRAE 52.2, or an average efficiency of 30 percent in accordance with ASHRAE 52.2. Before occupancy, filters shall be replaced with filters having a MERV 13 rating in accordance with Section E 603.3.

    Exception: Embedded hydronics system shall be permitted to be used to condition the building during construction.
After construction ends and interior finishes are installed, flush-out the building to reduce contaminant concentrations by supplying a total outdoor air volume of 14000 cubic feet per square foot (ft3/ft2) (4267.2 m3/m2) of occupiable building area. An internal temperature of not less than 60°F (16°C) and relative humidity not higher than 60 percent shall be maintained during the flush-out process. Occupancy shall begin on condition of 3500 ft3/ft2 (1066.8 m3/m2) of building area, with the remaining 10500 ft3/ft2 (3200.4 m3/m2) being accomplished as soon as possible.

Exception: Other means of reducing the contaminant concentration levels shall be permitted where approved by the Authority Having Jurisdiction.
At the time of rough installation, or during storage on the construction site and until final startup of the heating and cooling equipment, duct and other related air distribution component openings shall be covered with tape, plastic, sheet metal, or other methods acceptable to the enforcing agency to reduce the amount of dust or debris that collects in the system.
Rooms where activities produce hazardous fumes or chemicals, including commercial kitchens, garages, janitorial or laundry rooms, and copy or printing rooms, shall be exhausted and isolated from adjacent spaces in accordance with this code.
In mechanically ventilated buildings, particle filters, or air-cleaning devices shall be provided to clean outdoor and return air prior to its delivery to occupied spaces. The particle or air cleaner shall have a MERV of 13.

Exception: A filter or air cleaning device with a lower MERV value shall be permitted provided it is the highest value commercially available for the specific equipment that is installed.
Installations of HVAC and refrigeration shall not contain CFCs and shall be in accordance with this code.
Roof drainage systems shall discharge to a place of disposal in accordance with the plumbing code. Storm water shall be directed away from the building.
Rooms or occupied spaces within single-family homes and multifamily structures of three stories or less above grade shall be designed to have ventilation (outdoor) air for occupants in accordance with Section E 605.1.1 through Section E 605.1.3.2, or the applicable local code.
Naturally ventilated spaces shall be permanently open to and within 20 feet (6096 mm) of operable wall or roof openings to the outdoors, the openable area of which is not less than 5 percent of the conditioned floor area of the naturally ventilated space. Where openings are covered with louvers or otherwise obstructed, openable area shall be based on the free unobstructed area through the opening.
The means to open required operable openings shall be readily accessible to building occupants where the space is occupied.
Each space that is not naturally ventilated in accordance with Section E 605.1.1 shall be ventilated with a mechanical system capable of providing an outdoor air rate not less than 15 ft3/min (0.007 m3/s) per person times the expected number of occupants. Mechanical ventilation shall comply with this code.
A Mechanical exhaust system, supply system, or combination thereof shall be installed to operate for each dwelling unit to provide continuous whole-building ventilation with outdoor air rate not less than the rate specified in Section E 605.1.3.1.

Exception. An intermittently operating whole-building mechanical ventilation system shall be permitted where the ventilation rate is in accordance with Section E 605.1.7. The system shall be designed for automatic operation. [ASHRAE 62.2:4.1]
The total required ventilation, rate (Qtot) shall be as specified in Table E 605.1.3.1 or, alternatively, calculated in accordance with Equation E 605.1.3.1.

Qtot = 0.03Afloor + 7.5(Nbr + 1) (Equation E 605.1.3.1)
Where:
Qtot = total required ventilation rate, cubic feet
per minute (ft3/min)
Afloor = floor area of residence, square foot (ft2)
Nbr = number of bedrooms; not to be less than
one
For SI units: 1 cubic foot per minute = 0.00047 m3/s, 1 square foot = 0.0929 m2

TABLE E 605.1.3.1
VENTILATION AIR REQUIREMENTS, (cubic foot per minute)
[ASHRAE 62.2:TABLE 4.1a]
FLOOR AREA (ft2) BEDROOMS
1 2 3 4 5
< 500 30 38 45 53 60
501-1000 45 53 60 68 75
1001-1500 60 68 75 83 90
1501-2000 75 83 90 98 105
2001-2500 90 98 105 113 120
2501-3000 105 113 120 128 135
3001-3500 120 128 135 143 150
3501-4000 135 143 150 158 165
4001-4500 150 158 165 173 180
4501-5000 165 173 180 188 195
For SI units: 1 square foot = 0.0929 m2, 1 cubic fool per minute = 0.00047 m3/s

Exception: Whole-building mechanical systems shall not be required where the Authority Having Jurisdiction determines that window operation is a locally permissible method of providing ventilation and provided one or more of the following conditions is met:
  1. The building has no mechanical cooling and is located in zone 1 or 2.
  2. The building is thermally conditioned for human occupancy for less than 876 hours per year. [ASHRAE 62.2:4.1.1]
Table E 605.1.3.1 and Equation E 605.1.3.1 assume two persons in a studio or one-bedroom dwelling unit and an additional person for each additional bedroom. Where higher occupant densities are known, the rate shall be increased by 7.5 ft3/min (0.003 m3/s) for each additional person. Where approved by the Authority Having Jurisdiction, lower occupant densities shall be permitted to be used. [ASHRAE 62.2:4.1.3]
The whole-house ventilation system shall consist of one or more supply or exhaust fans and associated ducts and controls. Local exhaust fans shall be permitted to be part of a mechanical exhaust system. Where local exhaust fans are used to provide whole-building ventilation, the local exhaust airflow shall be permitted to be credited towards the whole-building ventilation airflow requirement. Outdoor air ducts connected to the return side of an air handler shall be permitted as supply ventilation where manufacturer's requirements for return air temperature are met. See ASHRAE 62.2 for guidance on selection of methods. [ASHRAE 62.2:4.2]
The airflow required by this section shall be the quantity of outdoor ventilation air supply, indoor air, or both exhausted by the mechanical ventilation system as installed and shall be measured using a flow hood, flow grid, or other airflow measuring device. Ventilation airflow of systems with multiple operating modes shall be tested in all modes designed to be in accordance with this section. [ASHRAE 62.2:4.3]
The "fan on" switch on a heating or air-conditioning system shall be permitted as an operational control for systems introducing ventilation air through a duct to the return side of an HVAC system. Readily accessible override control shall be provided to the occupant. Local exhaust fan switches and "fan-on" switches shall be permitted as override controls. Controls, including the "fan-on" switch of a conditioning system, shall be appropriately labeled. [ASHRAE 62.2:4.4]
Whole-building mechanical systems designed to provide intermittent ventilation shall be in accordance with Section E 605.1.7.1 and Section E 605.1.7.2. [ASHRAE 62.2:4.5]
Where mechanical ventilation is provided at least once every three hours by a system of one or more fans, the intermittent mechanical ventilation rate shall be calculated as the larger of the time average supply or exhaust airflow rate and shall be not less than specified in Section E 605.1.3. [ASHRAE 62.2:4.5.1]
Where mechanical ventilation is not provided at least once every three hours by a single fan system, the intermittent fan airflow rate (Qon) shall be calculated in accordance with Equation E 605.1.7.2(1). Fan cycle time (Tcyc) shall not exceed 24 hours. Where the fan airflow rate during the on-cycle varies with time, the time average airflow rate during each hour shall meet or exceed the intermittent mechanical ventilation requirement in accordance with Equation E 605.1.7.2(1).

QonQfan/(ε•f) [Equation E 605.1.7.2(1)]
Where:
Qon = intermittent fan airflow rate during the
on-cycle
Qfan = continuous mechanical ventilation air
requirement (from Table E 605.1.3.1
or Equation E 605.1.3.1)
ε = mechanical ventilation effectiveness
(from Table E 605.1.7.2)
f = fractional on-time. defined as the on
time for one cycle divided by the cycle
time.

Table E 605.1.7.2 also requires the calculation of the required turnover, N, in accordance with the following:

N = 12.8•QfanTcyc/Afloor [Equation E 605.1.7.2(2)]
Where:
Qfan = mechanical ventilation air requirement
(from Table E 605.1.3.1 or Equation E
605.1.3.1), ft3/min
Tcyc = fan cycle time, defined as the total
time for one off-cycle and one on
cycle, hours
Afloor = floor area of residence, ft2

For SI units: 1 cubic foot per minute = 0.00047 m3/s, 1 square foot =0.0929 m2

    For values not listed in Table 605.1.7.2, use the next higher value for N or the next lower value for f. Linear interpolation shall be permitted. [ASHRAE 62.2:4.5.2]

TABLE E 605.1.7.2
MECHANICAL VENTILATION EFFECTIVENESS (ε) FOR INTERMITTENNT FANS
[ASHRAE 62.2:TABLE 4.2]
A whole-building ventilation system shall be designed and operated in such a way as to provide the same or lower annual exposure as would be provided in accordance with Section E 605.1.3. The calculations shall be based on a single zone with a constant contaminant emission rate. The manufacturer, specifier, or designer of the equivalent ventilation system shall certify that the system is in accordance with this intent and provide supporting documentation. [ASHRAE 62.2:4.6]
Except where a whole house energy recovery system is used, a mechanical exhaust fan vented to the outdoors shall be provided in each room containing a bathtub, shower or tub/shower combination. The ventilation rate shall be not less than 50 ft3/min (0.02 m3/s) for intermittent operation and 20 ft3/min (0.009 m3/s) for continuous operation. Fans shall comply with the Energy Star Program.
Heating and air conditioning filters shall have a MERV rating of 6 or higher. The air distribution system shall be designed for the pressure drop across the filter.
The building shall comply with this code and ASHRAE 62.1 for ventilation air supply.
The mechanical systems and controls of building shall be designed to provide and maintain indoor comfort conditions in accordance with ASHRAE 55.
Heating and air-conditioning systems shall be sized, designed, and have their equipment selected in accordance with the following:
  1. Heat loss and heat gain are established in accordance with ACCA Manual J, ASHRAE handbooks, or other equivalent methods.
  2. Duct systems shall be sized in accordance with ACCA Manual D, ASHRAE handbooks, or other equivalent methods.
  3. Heating and cooling equipment in accordance with ACCA Manual S or other equivalent methods.
Primers and solvent cements used to join plastic pipe and fittings shall be in accordance with Section E 608.1.1 and Section E 608.1.2.
Solvent cement, including one-step solvent cement, shall have a volatile organic compound (VOC) content of less than or equal to 65 ounces per gallon (oz/gal) (487 g/L) for CPVC cement, 68 oz/gal (509 g/L) for PVC cement, and 43 oz/gal (322 g/L) for ABS cement, as determined by the South Coast Air Quality Management District's Laboratory Methods of Analysis for Enforcement Samples, Method 316A.
Primer shall have a volatile organic compound (VOC) content of less than or equal to 73 oz/gal (546 g/l), as determined by the South Coast Air Quality Management District's Laboratory Methods of Analysis for Enforcement Samples, Method 316A.
The provisions of this section address minimum qualifications of installers of mechanical systems covered within the scope of this appendix.
Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer, or service technician shall be licensed to perform such work.
The provisions of this section apply to the commissioning of commercial and institutional HVAC systems.
HVAC commissioning shall be included in the design and construction processes of the project to verify that the HVAC systems and components meet the owner's project requirements and in accordance with this appendix. Commissioning shall be performed in accordance with this appendix by personnel trained and certified in commissioning by a nationally recognized organization. Commissioning requirements shall include the following:
  1. Owner's project requirements
  2. Basis of design
  3. Commissioning measures shown in the construction documents
  4. Commissioning plan
  5. Functional performance
  6. Testing
  7. Post construction documentation and training
  8. Commissioning report
    HVAC systems and components covered by this appendix as well as process equipment and controls, and renewable energy systems shall be included in the scope of the commissioning requirements.
The performance goals and requirements of the HVAC system shall be documented before the design phase of the project begins. This documentation shall include not less than the following:
  1. Environmental and sustainability goals
  2. Energy efficiency goals
  3. Indoor environmental quality requirements
  4. Equipment and systems performance goals
  5. Building occupant and O&M personnel expectations
A written explanation of how the design of the HVAC system meets the owner's project requirements shall be completed at the design phase of the building project, and updated as necessary during the design and construction phases. The basis of design document shall cover not less than the following systems:
  1. Heating, ventilation, air conditioning (HVAC) systems and controls
  2. Water heating systems
  3. Renewable energy systems
A commissioning plan shall be completed to document the approach to how the project will be commissioned, and shall be started during the design phase of the building project. The commissioning plan shall include not less than the following:
  1. General project information
  2. Commissioning goals
  3. Systems to be commissioned. Plans to test systems and components shall include not less than the following:

    1. A detailed explanation of the original design intent.
    2. Equipment and systems to be tested, including the extent of tests.
    3. Functions to be tested.
    4. Conditions under which the test shall be performed.
    5. Measurable criteria for acceptable performance.
  4. Commissioning team information.
  5. Commissioning process activities, schedules, and responsibilities. Plans for the completion of commissioning requirements listed in Section E 802.5 through Section E 802.7 shall be included.
Functional performance tests shall demonstrate the correct installation and operation of each component, system, and system-to-system interface in accordance with the approved plans and specifications. Functional performance testing reports shall contain information addressing each of the building components tested, the testing methods utilized, and readings and adjustments made.
A system manual and systems operations training are required.
Documentation of the operational aspects of the HVAC system shall be completed within the systems manual and delivered to the building owner and facilities operator. The systems manual shall include not less than the following:
  1. Site information, including facility description, history, and current requirements.
  2. Site contact information.
  3. Basic O&M, including general site operating procedures, basic troubleshooting, recommended maintenance requirements, and site events log.
  4. Major systems.
  5. Site equipment inventory and maintenance notes.
  6. Equipment/system warranty documentation and information.
  7. "As-Built" design drawings.
  8. Other resources and documentation.
The training of the appropriate maintenance staff for each equipment type or system shall include not less than the following:
  1. System/Equipment overview (what it is, what it does, and what other systems or equipment it interfaces with).
  2. Review of the information in the systems manual.
  3. Review of the record drawings on the system/equipment
A complete report of commissioning process activities undertaken through the design, construction, and post-construction phases of the building project shall be completed and provided to the owner.
Part II of this appendix provides a means of verifying the commissioning requirements of Section E 802.1. The activities specified in Part II of this appendix includes three aspects, as described as follows:
  1. Visual inspection of the equipment and installation.
  2. Review of the certification requirements.
  3. Functional tests of the systems and controls.
Details of commissioning acceptance requirements shall be incorporated into the construction documents, including information that describes the details of the functional tests to be performed. This information shall be permitted to be integrated into the specifications for testing and air balancing, energy management and control system, equipment startup procedures or commissioning. It is possible that the work will be performed by a combination of the test and balance (TAB) contractor, mechanical/electrical contractor, and the energy management control system (EMCS) contractor, so applicable roles and responsibilities shall be clearly called out.
The roles and responsibilities of the persons involved in commissioning acceptance are included in Section E 803.2.1.1 through Section E 803.2.1.3.
The field technician shall be responsible for performing and documenting the results of the acceptance procedures on the certificate of acceptance forms. The field technician shall sign the certificate of acceptance to certify that the information he provides on the certificate of acceptance is true and correct.
The responsible person shall be the contractor or registered design professional of record. A certificate of acceptance shall be signed by a responsible person to take responsibility for the scope of work specified by the certificate of acceptance document. The responsible person shall perform the field testing and verification work, and where this is the case, the responsible person shall complete and sign both the field technician's signature block and the responsible person's signature block on the certificate of acceptance form. The responsible person assumes responsibility for the acceptance testing work performed by the field technician agent or employee.
The certificate of acceptance shall be submitted to the Authority Having Jurisdiction in order to receive the final certificate of occupancy. The Authority Having Jurisdiction shall not release a final certificate of occupancy unless the submitted certificate or acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.
Functional tests shall be performed on new equipment and systems installed in either new construction or retrofit applications in accordance with this section. The appropriate certificate of acceptance form along with each specific test shall be completed and submitted to the Authority Having Jurisdiction before a final occupancy permit can be granted.
Functional testing shall be performed on the devices and systems listed in this section. The functional test results are documented using the applicable certificate of acceptance forms shown in parenthesis and located in Section E 806.0. The functional tests shall be performed in accordance with Section E 805.0 using the following forms:
  1. Minimum ventilation controls for constant and variable air volume systems (Form MECH-2A)
  2. Zone temperature and scheduling controls for constant volume, single-zone, unitary air conditioner and heat pump systems (Form MECH-3A)
  3. Duct leakage on a subset of small single-zone systems depending on the ductwork location (Form MECH-4A)
  4. Air economizer controls for economizers that are not factory installed and tested (Form MECH-5A).
  5. Demand-controlled ventilation control systems (Form MECH-6A)
  6. Supply fan variable flow controls (Form MECH-7A)
  7. Valve leakage for hydronic variable flow systems and isolation valves on chillers and boilers in plants with more than one chiller or boiler being served by the same primary pumps through a common header (Form MECH-8A)
  8. Supply water temperature reset control strategies programmed into the building automation system for water systems (e.g., chilled, hot, or condenser water) (Form MECH-9A).
  9. Hydronic variable flow controls on a water system where the pumps are controlled by variable frequency drives (e.g., chilled and hot water systems; water-loop heat pump systems) (Form MECH-10A)
  10. Automatic demand shed control (Form MECH-11A)
  11. Fault detection and diagnostic for DX units (Form MECH-12A)
  12. Automatic fault detection and diagnostic systems (AFDD) (Form MECH-13A)
  13. Distributed energy storage DEC/DX AC systems (Form MECH-14A)
  14. Thermal energy storage (TES) systems (Form MECH-15A)
The functional testing process shall comply with Section E 804.3.1 through Section E 804.3.4.
The installing contractor, registered design professional of record, owner's agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall review the plans and specifications to ensure that they are in accordance with the acceptance requirements. This is typically done prior to signing a certificate of compliance.
The installing contractor, registered design professional of record, owner's agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall perform a construction inspection prior to testing to ensure that the equipment that is installed is capable of complying with the requirements of this appendix and is calibrated. The installation of associated systems and equipment necessary for proper system operation is required to be completed prior to the testing.
One or more field technicians shall perform the acceptance testing; identify performance deficiencies; ensure that they are corrected; and where necessary, repeat the acceptance procedures until the specified systems and equipment are performing in accordance with the acceptance requirements. The field technician who performs the testing shall sign the certificate of acceptance to certify the information has been provided to document the results of the acceptance procedures is true and correct.

    The responsible person shall review the test results from the acceptance requirement procedures provided by the field technician and sign the certificate of acceptance to certify compliance with the acceptance requirements. The responsible person shall be permitted to perform the field technician's responsibilities, and shall then sign the field technician declaration on the certificate of acceptance to certify that the information on the form is true and correct.
The Authority Having Jurisdiction shall not issue the final certificate of occupancy until required certificates of acceptance are submitted. Copies of completed, signed certificates of acceptance are required to be posted, or made available with the permit(s), and shall be made available to the Authority Having Jurisdiction.
This test ensures that adequate outdoor air ventilation is provided through the variable air volume air handling unit at two representative operating conditions. The test consists of measuring outdoor air values at maximum flow and at or near minimum flow. The test verifies that the minimum volume of outdoor air is introduced to the air handling unit where the system is in occupied mode at these two conditions of supply airflow. This test shall be performed in conjunction with supply fan variable flow controls test procedures to reduce the overall system testing time as both tests use the same two conditions of airflow for their measurements.
The procedure for performing a functional test for variable air volume systems shall be in accordance with Section E 805.1.1.1 and Section E 805.1.1.2.
Prior to functional testing, verify and document that the system controlling outside airflow is calibrated either in the field or factory.
The functional testing shall be in accordance with the following steps:

Step 1: Where the system has an outdoor air economizer, force the economizer high limit to disable economizer control (e.g., for a fixed drybulb high limit, lower the setpoint below the current outdoor air temperature).

Step 2: Adjust supply airflow to either the sum of the minimum zone airflows or 30 percent of the total design airflow. Verify and document the following:
  1. Measured outside airflow reading is within 10 percent of the total ventilation air called for in the certificate of compliance.
  2. OSA controls stabilize within 5 minutes.
Step 3: Adjust supply airflow to achieve design airflow. Verify and document the following:
  1. Measured outside airflow reading is within 10 percent of the total ventilation air called for in the certificate of compliance.
  2. OSA controls stabilize within 5 minutes.
Step 4: Restore system to "as-found" operating conditions.
System controlling outdoor air flow shall be calibrated in the field or at the factory.

    Measured outdoor airflow reading shall be within 10 percent of the total value found on the certificate of compliance under the following conditions:
  1. Minimum system airflow.
  2. Thirty percent of total design flow design supply airflow.
The purpose of this test is to ensure that adequate outdoor air ventilation is provided through the constant volume air handling unit to the spaces served under operating conditions. The intent of this test is to verify that the minimum volume of outdoor air is introduced to the air handling unit during typical space occupancy.
The procedure for performing a functional test for constant air volume systems shall be in accordance with Section E 805.2.1.1 and Section E 805.2.1.2.
Prior to functional testing, verify and document the following:
  1. Minimum position is marked on the outside air damper.
  2. The system has means of maintaining the minimum outdoor air damper position.
Where the system , has an outdoor air economizer, force the economizer to the minimum position and stop outside air damper modulation (e.g., for a fixed drybulb high limit, lower the setpoint below the current outdoor air temperature).
The system has a means of maintaining the minimum outdoor air damper position. The minimum damper position is marked on the outdoor air damper. The measured outside airflow reading shall be within 10 percent of the total ventilation air called for in the certificate of compliance.
The purpose of this test is to verify the individual components of a constant volume, single-zone, unitary air conditioner and heat pump system function correctly; including: thermostat installation and programming, supply fan, heating, cooling, and damper operation.
The procedure for performing a functional test for constant volume, single-zone, unitary air conditioner and heat pump systems shall be in accordance with Section E 805.3.1.1 and Section E 805.3.1.2.
Prior to functional testing, verify and document the following:
  1. Thermostat is located within the space-conditioning zone that is served by the HVAC system.
  2. Thermostat shall he in accordance with tempcrature adjustment and dead band requirements.
  3. Occupied, unoccupied, and holiday schedules shall be programmed per the facility's schedule.
  4. Preoccupancy purge is programmed.
The functional testing shall be in accordance with the following steps:

Stcp 1: Disable economizer and demand control ventilation systems (where applicable).

Step 2: Simulate a heating demand during the occupied condition. Verify and document the following:
  1. Supply fan operates continually.
  2. The unit provides heating.
  3. No cooling is provided by the unit.
  4. Outside air damper is at minimum position.
Step 3: Simulate operation in the dead band during occupied condition. Verify and document the following:
  1. Supply fan operates continually.
  2. Neither heating nor cooling is provided by the unit.
  3. Outside air damper is at minimum position.
Step 4: Simulate cooling demand during occupied condition. Lock out economizer (where applicable). Verify and document the following:
  1. Supply fan operates continually.
  2. The unit provides cooling.
  3. No heating is provided by the unit.
  4. Outside air damper is at minimum position.
Step 5: Simulate operation in the dead band during unoccupied mode. Verity and document the following:
  1. Supply fan is off.
  2. Outside air damper is fully closed.
  3. Neither heating nor cooling is provided by the unit.
Step 6: Simulate heating demand during unoccupied conditions. Verify and document the following:
  1. Supply fan is on (cither continuously or cycling).
  2. Heating is provided by the unit.
  3. No cooling is provided by the unit.
  4. Outside air damper is either closed or at minimum position.
Step 7: Simulate cooling demand during unoccupied condition. Lock out economizer (where applicable). Verify and document the following:
  1. Supply fan is on (either continuously or cycling).
  2. Cooling is provided by thc unit.
  3. No heating is providcd by the unit.
  4. Outside air damper is either closed or