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

This chapter shall apply to hydronic piping systems that are part of heating, cooling, ventilation, and air conditioning systems. Such piping systems include steam, hot water, chilled water, steam condensate, and ground source heat pump systems. The regulations of this chapter shall govern the construction, location, and installation of hydronic piping systems.
The temperature of surfaces within reach of building occupants shall not exceed 140°F (60°C) unless they are protected by insulation. Where sleeves are installed, the insulation shall continue full size through them.

    Coverings and insulation used for piping shall be of material approved for the operating temperature of the system and the installation environment. Where installed in a plenum, the insulation, jackets, and lap-seal adhesives, including pipe coverings and linings, shall have a flame-spread index not to exceed 25 and a smoke developed index not to exceed 50 where tested in accordance with ASTM E84 or UL 723.
The flow of the hydronic piping system shall be controlled to prevent water hammer.
Manifolds shall be equipped with a full-way isolation valve that is fully sealed on the supply and return lines. Manifolds shall be capable of withstanding the pressure and temperature of the system. The material of the manifold shall be compatible with the system fluid and shall be installed in accordance with the manufacturer's installation instructions.
Heat emitters shall be installed in accordance with the manufacturer's installation instructions.
Hydronic systems or parts thereof, shall be constructed in such a manner that polluted, contaminated water, or substances shall not enter a portion of the potable water system either during normal use or where the system is subject to pressure that exceeds the operating pressure in the potable water system. Piping, components, and devices in contact with the potable water shall be approved for such use and where an additive is used it shall not affect the performance of the system.
Where systems include an additive, chemical injection or provisions for such injection, the potable water supply shall be protected by a reduced-pressure principle backflow prevention assembly listed or labeled in accordance with ASSE 1013. Such additive or chemical shall be compatible with system components.
Where materials in the hydronic system are not suitable for use in a potable water system, such potable water shall not be used. Where a heat exchanger is installed with a dual purpose water heater, such application shall comply with the requirements for a single wall heat exchanger in Section 1218.1.
The heat source shall be sized to the design load.
Water heaters utilized for combined space-heating and water-heating applications shall be listed or labeled in accordance with the standards referenced in Table 1203.2, and shall be installed in accordance with the manufacturer 's installation instructions. The total heating capacity of a dual purpose water heater shall be based on the sum of the potable hot water requirements and the space heating design requirements corrected for hot water first hour draw recovery.

TABLE 1203.2
WATER HEATERS
TYPE STANDARDS
Gas, 75000 Btu/h or less CSA Z21.10.1
Gas, Above 75000 Btu/h CSA Z21.10.3
Electric, Space Heating UL 834
Solid Fuel UL 2523
For SI units: 1000 British thermal units per hour = 0.293kW
The output performance on tankless water heaters shall be determined by the temperature rise and flow rate of water through the unit. The ratings shall be expressed by the water temperature rise at a given flow rate. Manufacturers flow rates shall not be exceeded.
In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 1204.2 through Section 1204.5.
Each system shall be identified with a colored pipe or band and coded with paint, wraps, and materials compatible with the piping.
Potable water systems shall be identified with a green background with white lettering. The minimum size of letters and length of the color field shall be in accordance with Table 1204.3.

TABLE 1204.3
MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS
OUTSIDE DIAMETER OF
PIPE OR COVERING
(inches)
MINIMUM LENGTH OF
COLOR FIELD
(inches)
MINIMUM SIZE OF
LETTERS
(inches)
12 to 114 8 12
112 to 2 8 34
212 to 6 12 114
8 to 10 24 212
Over 10 32 312
For SI units: 1 inch = 25.4 mm
Nonpotable water systems shall have a yellow background with black uppercase lettering, with the words "CAUTION: NONPOTABLE WATER, DO NOT DRINK." Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 1204.3.
The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.
Flow directions shall be indicated on the system.
Operating and maintenance information shall be provided to the building owner.
System piping and components shall be tested with a pressure of not less than one and one-half times the operating pressure but not less than 100 psi (689 kPa). Piping shall be tested with water or air except that plastic pipe shall not be tested with air. Test pressures shall be held for a period of not less than 30 minutes with no perceptible drop in pressure. These tests shall be made in the presence of the Authority Having Jurisdiction.
Heat sources, system piping and tubing shall be flushed after installation with water or a cleaning solution. Cleaning of the heat source shall comply with the manufacturer's instructions. The cleaning solution shall be compatible with all system components and shall be used in accordance with the manufacturer's instructions. The heat source shall be disconnected from the piping system or protected with a fine mesh strainer during flushing to prevent debris from being deposited into the heat source.
PEX, PE-RT, and PB tubing in closed hydronic systems shall contain an oxygen barrier.
Hydronic systems containing pressurized fluids shall be protected against pressures and temperatures exceeding design limitations with a pressure and temperature relief valve. Each section of the system in which excessive pressures are capable of developing shall have a relief valve located so that a section is not capable of being isolated from a relief device. Pressure and temperature relief valves shall be installed in accordance with the terms of their listing and the manufacturer's installation instructions.
Pressurized vessels shall be provided with overpressure protection by means of a listed pressure relief valve installed in accordance with the manufacturer's installation instructions.
The discharge piping serving a temperature relief valve, pressure relief valve, or combination of both shall have no valves, obstructions, or means of isolation and be provided with the following:
  1. Equal to the size of the valve outlet and shall discharge full size to the flood level of the area receiving the discharge and pointing down.
  2. Materials shall be rated at not less than the operating temperature of the system and approved for such use.
  3. Discharge pipe shall discharge independently by gravity through an air gap into the drainage system or outside of the building with the end of the pipe not exceeding 2 feet (610 mm) and not less than 6 inches (152 mm) above the ground and pointing downwards.
  4. Discharge in such a manner that does not cause personal injury or structural damage.
  5. No part of such discharge pipe shall be trapped or subject to freezing.
  6. The terminal end of the pipe shall not be threaded.
  7. Discharge from a relief valve into a water heater pan shall be prohibited.
Heating appliances, equipment, safety and operational controls shall be listed for its intended use in a hydronic heating system and installed in accordance with the manufacturer's installation instructions.
Boilers and their control systems shall comply with Section 1002.0.
A condensing boiler, in which the heat exchanger and venting system are designed to operate with condensing flue gases, shall be permitted to be connected directly to the panel heating system without a protective mixing device.
Where the heat exchanger and venting system are not designed to operate with condensed flue gases, the boiler shall be permitted to connect directly to the panel heating system where protected from flue gas condensation. The operating temperature of the boiler shall be more than the fluid temperature in accordance with the manufacturer's instructions.
Water heaters used for combined space- and water-heating applications shall be in accordance with the standards referenced in Table 1203.2, and shall be installed in accordance with the manufacturer's installation instructions. The total heating capacity of a dual purpose water heater shall be based on the sum of the potable hot water requirements and the space heating design requirements corrected for hot water first hour draw recovery.
Where a combined space- and water-heating application requires water for space heating at temperatures exceeding 140°F (60°C), a thermostatic mixing valve that is in accordance with ASSE 1017 shall be installed to temper the water supplied to the potable water distribution system to a temperature of 140°F (60°C) or less.
Solar water heating systems used in hydronic panel radiant heating systems shall be installed in accordance with the Uniform Solar Energy Code and Hydronics Code (USEHC).
Circulators shall be listed for their intended use based on the heat transfer medium. Circulators shall be installed to allow for service and maintenance. The manufacturer's installation instructions shall be followed for correct orientation and installation.
The circulator shall be installed in such a way that strain from the piping is not transferred to the circulator housing. The circulator shall be permitted to be directly connected to the piping, provided the piping is supported on each side of the circulator. Where the installation of a circulator will cause strain on the piping, the circulator shall be installed on a mounting bracket or base plate. Where means for controlling vibration of a circulator is required, an approved means for support and restraint shall be provided.
The selection and sizing of a circulator shall be based on all of the following:
  1. Loop or system head pressure, feet of head (m)
  2. Capacity, gallons per minute (L/s)
  3. Maximum and minimum velocity, feet per second (m/s)
  4. Maximum and minimum temperature, °F (°C)
  5. Maximum working pressure, pounds per square inch (kPa)
  6. Fluid type
An expansion tank shall be installed in every hydronic system to control thermal expansion. Secondary hot water systems, that are isolated from the primary system by a heat exchanger shall install a separate expansion tank and pressure relief valve. Expansion tanks shall be of the closed or open type. Expansion tanks used in hydronic systems shall comply with the requirements of ASME Boiler and Pressure Vessel Code Section VIII where the system is designed to operate at more than 30 pounds-force per square inch (psi) (207 kPa). Tanks shall be rated for the pressure of the system. Expansion tanks shall be accessible for maintenance and shall be installed in accordance with the manufacturer's installation instructions.
A closed expansion tank shall be sized based on the capacity of the system. The minimum size of the tank shall be determined in accordance with Section 1004.4 and shall be equipped with an airtight tank or other air cushion that is consistent with the volume and capacity of the system. Tanks shall be equipped with a drain valve and a manual air vent. Tanks shall be located in accordance with the manufacturer's instructions unless otherwise specified by the system design. Each tank shall be equipped with a shutoff device that will remain open during operation of the heating system. Valve handles shall be locked open or removed to prevent from being inadvertently shut off.
An open expansion tank shall be located not less than 36 inches (914 mm) above the highest point in the system and shall be sized based on the capacity of the system. An overflow with a diameter of not less than one-half the size of the water supply or not less than 1 inch (25 mm) in diameter shall be installed at the top of the tank. The overflow shall discharge through an air gap into the drainage system. Isolation valves shall not be installed in the piping between the heat-distribution system and the expansion tank. Tanks shall be located in accordance with the manufacturer's instructions unless otherwise specified by the system design. Each tank shall be equipped with a shutoff device that will remain open during operation of the heating system. Valve handles shall be locked open or removed to prevent from being inadvertently shut off.
Hydronic pipe and tubing shall comply with the applicable standards referenced in Table 1210.1 and shall be approved for use based on the intended purpose. Materials shall be rated for the operating temperature and pressure of the system and shall be compatible with the type of transfer medium. Pipe fittings and valves shall be approved for the installation with the piping, materials to be installed and shall be in accordance with the applicable standards referenced in Table 1210.1. Exterior piping shall be protected against freezing, UV radiation, corrosion and degradation. Embedded pipe or tubing shall comply with Section 1221.2.

TABLE 1210.1
MATERIALS FOR HYDRONIC SYSTEM PIPING, TUBING, AND FITTINGS
MATERIAL STANDARDS
PIPING/TUBING FITTINGS
Copper/Copper Alloy ASTM B42, ASTM B43, ASTM B75, ASTM
B88, ASTM B135, ASTM B2512, ASTM B302,
ASTM B447
ASME B16.15, ASME B16.18, ASME B16.22,
ASME B16.23, ASME B16.24, ASME B16.26,
ASME B16.29, ASME B16.51
Ductile Iron AWWA C115/A21.15, AWWA C151/A21.51 AWWA C110/A21.101, AWWA C153/A21.53
Steel ASTM A53, ASTM A106, ASTM A254 ASME B16.5, ASME B16.9, ASME B16.11,
ASTM A420
Gray Iron - ASTM A126
Malleable Iron - ASME B16.3
Acrylonitrile Butadiene Styrene
(ABS)
ASTM D1527 -
Chlorinated Polyvinyl Chloride
(CPVC)
ASTM D2846, ASTM F441, ASTM D442 ASTM D2846, ASTM F437, ASTM F438,
ASTM F439, ASTM F1970
Polyethylene (PE) Pipe ASTM D1693, ASTM D2513, ASTM D2683,
ASTM D2837, ASTM D3035, ASTM D3350,
ASTM F1055
ASTM d2609, ASTM D2683, ASTM D3261,
ASTM F1055, CSA B137.1
Cross-Linked Polyethylene (PEX) ASTM F876, ASTM F877 ASTM F877, ASTM F1807, ASTM F1960,
ASTM F1961, ASTM F2080, ASTM F2159,
CSA B137.5
Polypropylene (PP) ASTM F2389 -
Polyvinyl Chloride (PVC) ASTM D1785, ASTM D2241 ASTM D2464, ASTM D2466, ASTM D2467,
ASTM F1970
Raised Temperature Polyethylene
(PE-RT)
ASTM F2623, ASTM F2769 ASTM F1807, ASTM F2159, ASTM F2735,
ASTM F2769
Cross-Linked Polyethylene/Aluminum
/Cross-Linked Polyethylene
(PEX-AL-PEX)
ASTM F1281, CSA B137.10 ASTM F1281, ASTM F1974, ASTM F2434,
CSA B137.10
Polyethylene/Aluminum/Polyethylene
(PE-AL-PE)
ASTM F1282, CSA B137.9 ASTM F1282, ASTM F1974, CSA B1379

Notes:
1   Ductile and gray iron.
2   Only type K, L, or M tubing allowed to be installed.
Pipe and tubing shall be so installed that it will not be subject to undue strains or stresses, and provisions shall be made for expansion, contraction, and structural settlement. [OSHPD 1, 2 & 4] Pipe connections less than 212 inches (64 mm) to heating coils, cooling coils, humidifiers, and similar equipment shall have flexible connectors or three (3) 90-degree offsets in close proximity of the connection.
Pipe and tubing shall be supported in accordance with Table 313.3. Systems with valves, circulators, and expansion tanks shall be provided with additional support in accordance with this code and manufacturer's installation instructions.
Joints and connections shall be of an approved type. Joints shall be gas and watertight and designed for the pressure of the hydronic system. Changes in direction shall be made by the use of fittings or with pipe bends having a radius of not less than six times the outside diameter of the tubing. Joints between pipe and fittings shall be installed in accordance with the manufacturer's installation instructions.
Joints between chlorinated polyvinyl chloride (CPVC) pipe or fittings shall be installed in accordance with one of the following methods:
  1. Removable and non-removable push fit fittings with an elastomeric o-ring that employ quick assembly push fit connectors shall be in accordance with ASSE 1061.
  2. Solvent cement joints for CPVC pipe and fittings shall be clean tram 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 all inch (15 mm) through 2 inches (50 mm) in diameter or ASTM F442, 12 of an inch (15 mm) through 3 inches (80 mm) in diameter. Apply primer where required inside the fitting and to the depth of the fitting on pipe. Apply liberal coat of cement to the outside surface of pipe to depth of fitting and inside of fitting. Place pipe inside fitting to forcefully bottom the pipe in the socket and hold together until joint is set.
  3. Threaded joints for CPVC pipe shall be made with pipe threads in accordance with ASME B1.20.1. A minimum of Schedule 80 shall be permitted to be threaded; and the pressure rating shall be reduced by 50 percent. The use of molded fittings shall not result in a 50 percent reduction in the pressure rating of the pipe provided that the molded fittings shall be fabricated so that the wall thickness of the material is maintained at the threads. Thread sealant compound that is compatible with the pipe and fitting, insoluble in water, and nontoxic shall be applied to male threads. Caution shall be used during assembly to prevent over tightening of the CPVC components once the thread sealant has been applied. Female CPVC threaded fittings shall be used with plastic male threads only.
Joints between copper pipe, tubing, or fittings shall be installed in accordance with one of the following methods:
  1. Brazed joints between copper or copper alloy pipe, tubing, or fittings shall be made with brazing alloys having a liquid temperature above 1000°F (538°C). The joint surfaces to be brazed shall be cleaned bright by either manual or mechanical means. Tubing shall be cut square and reamed to full inside diameter. Brazing flux shall be applied to the joint surfaces where required by manufacturer's recommendation. Brazing filler metal in accordance with AWS A5.8 shall be applied at the point where the pipe or tubing enters the socket of the fitting.
  2. Flared joints for soft copper or copper alloy tubing shall be made with fittings that are in accordance with the applicable standards referenced in Table 1210.1. Pipe or tubing shall be cut square using an appropriate tubing cutter. The tubing shall be reamed to full inside diameter, resized to round, and expanded with a proper flaring tool.
  3. Mechanically formed tee fittings shall have extracted collars that shall be formed in a continuous operation consisting of drilling a pilot hole and drawing out the pipe or tube surface to form a collar having a height not less than three times the thickness of the branch tube wall. The branch pipe or tube shall be notched to conform to the inner curve of the run pipe or tube and shall have two dimple depth stops to ensure that penetration of the branch pipe or tube into the collar is of a depth for brazing and that the branch pipe or tube does not obstruct the flow in the main line pipe or tube. Dimple depth stops shall be in line with the run of the pipe or tube. The second dimple shall be 14 of an inch (6.4 mm) above the first and shall serve as a visual point of inspection. Fittings and joints shall be made by brazing. Soldered joints shall not be permitted.
  4. Pressed fittings for copper or copper alloy pipe or tubing shall have an elastomeric o-ring that forms the joint. The pipe or tubing shall be fully inserted into the fitting, and the pipe or tubing marked at the shoulder of the fitting. Pipe or tubing shall be cut square, chamfered, and reamed to full inside diameter. The fitting alignment shall be checked against the mark on the pipe or tubing to ensure the pipe or tubing is inserted into the fitting. The joint shall be pressed using the tool recommended by the manufacturer.
  5. Removable and nonremovable push fit fittings for copper or copper alloy tubing or pipe that employ quick assembly push fit connectors shall be in accordance with ASSE 1061. Push fit fittings for copper pipe or tubing shall have an approved elastomeric o-ring that forms the joint. Pipe or tubing shall be cut square, chamfered, and reamed to full inside diameter. The tubing shall be fully inserted into the fitting, and the tubing marked at the shoulder of the fitting. The fitting alignment shall be checked against the mark on the tubing to ensure the tubing is inserted into the fitting and gripping mechanism has engaged on the pipe.
  6. Soldered joints between copper or copper alloy pipe, tubing, or fittings shall be made in accordance with ASTM B828. Pipe or tubing shall be cut square and reamed to the full inside diameter including the removal of burrs on the outside of the pipe or tubing. Surfaces to be joined shall be cleaned bright by manual or mechanical means. Flux shall be applied to pipe or tubing and fittings and shall be in accordance with ASTM B813, and shall become noncorrosive and nontoxic after soldering. Insert pipe or tubing into the base of the fitting and remove excess flux. Pipe or tubing and fitting shall be supported to ensure a uniform capillary space around the joint. Solder in accordance with ASTM B32 shall be applied to the joint surfaces until capillary action draws the molten solder into the cup. Joint surfaces shall not be disturbed until cool and any remaining flux residue shall be cleaned.
  7. Threaded joints for copper or copper alloy pipe shall be made with pipe threads in accordance with ASME B1.20.1. Thread sealant tape or compound shall be applied only on male threads, and such material shall be of approved types, insoluble in water, and nontoxic.
Joints between cross-linked polyethylene (PEX) pipe or fittings shall be installed with fittings for PEX tubing that comply with the applicable standards referenced in Table 1210.1. PEX tubing labeled in accordance with ASTM F876 shall be marked with the applicable standard designation for the fittings specified for use with the tubing. Mechanical joints shall be installed in accordance with the manufacturer's installation instructions.
Joints between cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pipe or fittings shall be installed in accordance with one of the following methods:
  1. Mechanical joints between PEX-AL-PEX pipe or fittings shall include mechanical and compression type fittings and insert fittings with a crimping ring. Insert fittings utilizing a crimping ring shall be in accordance with ASTM F1974 or ASTM F2434. Crimp joints for crimp insert fittings shall be joined to PEX-AL-PEX pipe by the compression of a crimp ring around the outer circumference of the pipe, forcing the pipe material into annular spaces formed by ribs on the fitting.
  2. Compression joints shall include compression insert fittings and shall be joined to PEX-AL-PEX pipe through the compression of a split ring or compression nut around, the outer circumference of the pipe, forcing the pipe material into the annular space formed by the ribs on the fitting.
Joints between ductile iron pipe or fittings shall be installed in accordance with one of the following methods:
  1. Mechanical joints for ductile iron pipe or fittings shall consist of a bell that is cast integrally with the pipe or fitting and provided with an exterior flange having bolt holes and a socket with annular recesses for the sealing gasket and the plain end of the pipe or fitting. The elastomeric gasket shall comply with AWWA C111. Lubricant recommended for the application by the pipe manufacturer shall be applied to the gasket and plain end of the pipe.
  2. Push-on joints for ductile iron pipe or fittings shall consist of a single elastomeric gasket that shall be assembled by positioning the elastomeric gasket in an annular recess in the pipe or fitting socket and forcing the plain end of the pipe or fitting into the socket. The plain end shall compress the elastomeric gasket to form a positive seal and shall be designed so that the elastomeric gasket shall be locked in place against displacement. The elastomeric gasket shall comply with AWWA C111. Lubricant recommended for the application by the pipe manufacturer shall be applied to the gasket and plain end of the pipe.
Joints between polyethylene (PE) plastic pipe, tubing, or fittings shall be installed in accordance with one of the following:
  1. Butt-fusion joints shall be installed in accordance with ASTM F2620 and shall be made by heating the squared ends of two pipes, pipe and fitting, or two fittings by holding ends against a heated element. The heated element shall be removed where the proper melt is obtained and joined ends shall be placed together with applied force.
  2. Electro-fusion joints shall be heated internally by a conductor at the interface of the joint. Align and restrain fitting to pipe to prevent movement and apply electric current to the fitting. Tum off the current when the proper time has elapse to heat the joint. The joint shall fuse together and remain undisturbed until cool.
  3. Socket-fusion joints shall be installed in accordance ASTM F2620 and shall be made by simultaneously heating the outside surface of a pipe end and the inside of a fitting socket. Where the proper melt is obtained, the pipe and fitting shall be joined by inserting one into the other with applied force. The joint shall fuse together and remain undisturbed until cool.
  4. Mechanical joints between PE pipe, tubing, or fittings shall include insert and mechanical compression fittings that provide a pressure seal resistance to pullout. Joints for insert fittings shall be made by cutting the pipe square, using a cutter designed for plastic piping, and removal of sharp edges. Two stainless steel clamps shall be placed over the end of the pipe. Fittings shall be checked for proper size based on the diameter of the pipe. The end of pipe shall be placed over the barbed insert fitting, making contact with the fitting shoulder. Clamps shall be positioned equal to 180 degrees (3.14 rad) apart and shall be tightened to provide a leak tight joint. Compression type couplings and fittings shall be permitted for use in joining PE piping and tubing. Stiffeners that extend beyond the clamp or nut shall be prohibited. Bends shall be not less than 30 pipe diameters, or the coil radius where bending with the coil. Bends shall not be permitted closer than 10 pipe diameters of a fitting or valve. Mechanical joints shall be designed for their intended use.
Joints between polyethylene/aluminum/polyethylene (PE-AL-PE) pipe or fittings shall be installed in accordance with one of the following methods:
  1. Mechanical joints for PE-AL-PE pipe, tubing, or fittings shall be either of the metal insert fittings with a split ring and compression nut or metal insert fittings with copper crimp rings. Metal insert fittings shall comply with ASTM F1974. Crimp insert fittings shall be joined to the pipe by placing the copper crimp ring around the outer circumference of the pipe, forcing the pipe material into the space formed by the ribs on the fitting until the pipe contacts the shoulder of the fitting. The crimp ring shall then be positioned on the pipe so the edge of the crimp ring is 18 of an inch (3.2 mm) to 14 of an inch (6.4 mm) from the end of the pipe. The jaws of the crimping tool shall be centered over the crimp ring and tool perpendicular to the barb. The jaws shall be closed around the crimp ring and shall not be crimped more than once.
  2. Compression joints for PE-AL-PE pipe, tubing, or fittings shall be joined through the compression of a split ring, by a compression nut around the circumference of the pipe. The compression nut and split ring shall be placed around the pipe. The ribbed end of the fitting shall be inserted onto the pipe until the pipe contacts the shoulder of the fitting. Position and compress the split ring by tightening the compression nut onto the insert fitting.
Joints between polyethylene of raised temperature (PE-RT) tubing or fittings shall be installed with fittings for PE-RT tubing that comply with the applicable standards referenced in Table 1210.1. Metal insert fittings, metal compression fittings, and plastic fittings shall be manufactured to and marked in accordance with the standards for fittings in Table 1210.1.
Joints between polypropylene pipe or fittings shall be installed in accordance with one of the following methods:
  1. Heat-fusion joints for polypropylene (PP) pipe shall be installed with socket-type heat-fused polypropylene fittings, butt-fusion polypropylene fittings or pipe, or electro-fusion polypropylene fittings. 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 or CSA B137.11.
  2. Mechanical and compression sleeve joints shall be installed in accordance with the manufacturer's installation instructions. Polypropylene pipe shall not be threaded. Polypropylene transition fittings for connection to other piping materials shall only be threaded by the use of copper alloy or stainless steel inserts molded in the fitting.
Joints between polyvinyl chloride pipe or fittings shall be installed in accordance with one of the following methods:
  1. Mechanical joints shall be designed to provide a permanent seal and shall be of the mechanical or push-on joint. The mechanical joint shall include a pipe spigot that has a wall thickness to withstand without deformation or collapse; the compressive force exerted where the fitting is tightened. The push-on joint shall have a minimum wall thickness of the bell at any point between the ring and the pipe barrel. The elastomeric gasket shall comply with ASTM D3139, and be of such size and shape as to provide a compressive force against the spigot and socket after assembly to provide a positive seal.
  2. Solvent cement joints for PVC pipe or fittings shall be clean from dirt and moisture. Pipe shall be cut square and pipe shall be deburred. Where surfaces to be joined are cleaned and free of dirt, moisture, oil, and other foreign material, apply primer purple in color in accordance with ASTM F656. Primer shall be applied until the surface of the pipe and fitting is softened. Solvent cements in accordance with ASTM D2564 shall be applied to all joint surfaces. Joints shall be made while both the inside socket surface and outside surface of pipe are wet with solvent cement. Hold joint in place and undisturbed for 1 minute after assembly.
  3. Threads shall comply with ASME B1.20.1. A minimum of Schedule 80 shall be permitted to be threaded; however, the pressure rating shall be reduced by 50 percent. The use of molded fittings shall not result in a 50 percent reduction in the pressure rating of the pipe provided that the molded fittings shall be fabricated so that the wall thickness of the material is maintained at the threads. Thread sealant compound that is compatible with the pipe and fitting, insoluble in water, and nontoxic shall be applied to male threads. Caution shall be used during assembly to prevent over tightening of the PVC components once the thread sealant has been applied. Female PVC threaded fittings shall be used with plastic male threads only.
Joints between steel pipe, tubing, or fittings shall be installed in accordance with one of the following methods:
  1. Mechanical joints shall be made with an approved and listed elastomeric gasket.
  2. Threaded joints shall be made with pipe threads that are in accordance with ASME B1.20.1. Thread sealant tape or compound shall be applied only on male threads, and such material shall be of approved types, insoluble in water, and nontoxic.
  3. Welded joints shall be made by electrical are or oxygen/acetylene method. Joint surfaces shall be cleaned by an approved procedure. Joints shall be welded by an approved filler metal.
  4. Pressed joints shall have an elastomeric o-ring that forms the connection. The pipe or tubing shall be fully inserted into the fitting, and the pipe or tubing marked at the shoulder of the fittings. Pipe or tubing shall be cut square, chamfered, and reamed to full inside diameter. The fitting alignment shall be checked against the mark on the pipe or tubing to ensure the pipe or tubing is fully inserted into the fitting. The joint shall be pressed using the tool recommended by the manufacturer.
Joints between various materials shall be installed in accordance with the manufacturer's installation instructions and shall comply with Section 1211.13.1 and Section 1211.13.2.
Joints from copper or copper alloy pipe or tubing to threaded pipe shall be made by the use of copper alloy adapter, copper alloy nipple [minimum 6 inches (152 mm)], dielectric fitting, or dielectric union in accordance with ASSE 1079. The joint between the copper or copper alloy pipe or tubing and the fitting shall be a soldered, brazed, flared, or pressed joint and the connection between the threaded pipe and the fitting shall be made with a standard pipe size threaded joint.
Where connecting plastic pipe to other types of piping, approved types of adapter or transition fittings designed for the specific transition intended shall be used.
Valves shall be rated for the operating temperature and pressure of the system. Valves shall be compatible with the type of heat transfer medium and piping material.
Valves shall be installed in hydronic piping systems in accordance with Section 1212.3 through Section 1212.11.
Isolation valves shall be installed on the supply and return side of the heat exchanger.
Isolation valves shall be installed on connections to pressure vessels.
Isolation valves shall be installed on both sides of a pressure reducing valve.
Serviceable equipment, components, and appliances within the system shall have isolation valves installed upstream and downstream of such devices.
Isolation valves shall be installed at connections to non-diaphragm-type expansion tanks.
Where flow balancing valves are installed, such valves shall be capable of increasing or decreasing the amount of flow by means of adjustment.
Where mixing or temperature control valves are installed, such valves shall be capable of obtaining the design water temperature and design flow requirements.
An approved type check valve shall be installed on liquid heat transfer piping to control thermosiphoning of heated liquids.
Isolation valves shall be installed where air removal devices or automatic air vents are utilized to permit cleaning, inspection, or repair without shutting the system down.
A heat source or system of commonly connected heat sources shall be protected by a water-temperature-activated operating control to stop heat output of the heat source where the system water reaches a pre-set operating temperature.
Radiant floor heating panels shall be protected with a high-limit control set 20°F (11°C) above the maximum design water temperature for the panel to prevent the introduction of heat into the panel. The high-limit setting shall not exceed the temperature rating for the pipe and shall be equipped with a manual reset.
A steam heat source or system of commonly connected steam heat sources shall be protected by a pressure-actuated control to shut off the fuel supply where the system pressure reaches a pre-set operating pressure.
A primary water-level control shall be installed on a steam heat source to control the water level in the heat source. The control shall be installed in accordance with the manufacturer's installation instructions.
An air-temperature-sensing device shall be installed in the occupied space to regulate the operation of the heat-distribution system.
Where a minimum return-water temperature to the heat source is specified, the heating system shall be designed and installed to ensure that the minimum return-water temperature is maintained during the normal operation of the heat source.
A means for balancing distribution loops, heat emitting devices, and multiple-boiler installations shall be provided in accordance with the manufacturer's instructions. A means for balancing and flow control shall include the piping design, pumping equipment, or balancing devices.
Direct-fired heat sources within a closed heating system shall have a low-water fuel cut-off device, except as specified in Section 1214.3. Where a low-water control is integral with the heat source as part of the appliance's integrated control, and is listed for such use, a separate low-water control shall not be required. An external cut-off device shall be installed in accordance with the heat-source manufacturer's installation instructions. No valve shall be located between the external low-water fuel cut-off and the heat-source unit. Where a pumped condensate return is installed, a second low-water cut-off shall be provided.
A direct-fired heat source, requiring forced circulation to prevent overheating, shall have a flow-sensing device installed with the appliance or such device shall be integral with the appliance. A low-water fuel cut-off device shall not be required.
Where an automatic makeup water supply fill device is used to maintain the water content of the heat-source unit, or any closed loop in the system, the makeup supply shall be located at the expansion tank connection.

    A pressure-reducing valve shall be installed on the makeup water feed line. The pressure of the feed line shall be set as specified in the design of the system, and connections to potable water shall be in accordance with Section 1202.0 to prevent contamination due to backflow.
Provisions shall be made to control zone flows in a multi-zone hydronic system where the closing of some or all of the two-way zone valves causes excess flow through the open zones or deadheading of a fixed-speed pump.
Where a differential pressure bypass valve is used for the purpose specified in Section 1214.5, it shall be installed and adjusted to provide bypass of the distribution system where the zones are closed.
Provision shall be made for the removal of air in the heat-distribution piping system. The air-removal device shall be located in the area of the heat-distribution piping system where air accumulates. Air-removal devices shall be installed to facilitate their removal for examination, repair, or replacement.
An air-separation device shall be installed on a closed heat-distribution system. The device shall be located in accordance with the manufacturer's installation instructions or at the point in the heat-distribution system where there is no pressure change and the water in the heat-distribution system is at the highest temperature.
Secondary loops that are isolated from the primary heat-distribution loop by a heat exchanger shall have an air-removal device or an air-separation device in accordance with Section 1214.6 or Section 1214.7.
Based on the system design, the heat-distribution units shall be selected in accordance with the manufacturer's specifications.
Heat-distribution units shall be installed in accordance with the manufacturer's installation instructions and this code.
Hydronic heat-distribution units or other system components shall be designed, installed, and protected from freezing.
System loops shall be installed so that the design flow rates are achieved within the system.
The flash point of a transfer fluid in a hydronic piping system shall be a minimum of 50°F (28°C) above the maximum system operating temperature. The transfer fluid shall be compatible with the makeup water supplied to the system.
For other than one-pipe steam systems, each heat-distribution unit shall be supplied with a steam trap that is listed for the application.
Two-pipe steam system piping and heat-distribution units shall be sloped down at 18 inch per foot (10.4 mm/m) in the direction of the steam flow.
One-pipe steam system piping and heat-distribution units shall be sloped down at 18 inch per foot (10.4 mm/m) towards the steam boiler, without trapping.
Steam automatic air vents shall be installed to eliminate air pressure in heat-distribution units on gravity steam piping systems. Steam traps shall be installed on pump and receiver condensate systems to eliminate negative pressures in coils and heat exchangers on a low-pressure steam system. Air vents shall not be used on a vacuum system.
System piping shall be installed to allow condensate to flow from the steam trap to the condensate tank or steam boiler.
Where multi-row elements are installed in an enclosure, they shall be top fed and piped in parallel down to the steam trap. A single steam trap for each row of heating elements shall be installed. Where the size of the return header is increased by a minimum of one pipe size, a single steam trap shall be permitted to be installed for multiple rows. Where multiple steam unit heaters are installed, an individual steam trap for each unit shall be installed.
Radiant heating and cooling panels shall be installed in accordance with the system design.
Floor surface temperatures shall not exceed the following temperatures:
  1. 85°F (29°C) in dwellings, buildings, or structures.
  2. 85°F (29°C) in occupancies where prolonged foot contact with the floor, and solid or laminated hardwood flooring.
  3. 90°F (32°C) in bathrooms and indoor swimming pools.
    The radiant heating panel temperature shall not exceed the maximum temperature rating of the materials used in the construction of the radiant heating panel. The radiant panel shall be protected with a high-limit control in accordance with Section 1213.2.
Chilled water systems for cooling shall be designed to minimize the potential for condensation. Chilled water piping, valves, and fittings shall be insulated and vapor sealed to prevent surface condensation.
A chilled ceiling or chilled floor panels used for space cooling shall be installed in a humidity-controlled environment. An air handling device that removes humidity shall be incorporated into the system to keep the relative humidity below 70 percent. A humidity sensor shall be installed within the space to turn off the panels where the surface approaches the dew point.
Hydronic radiant panel tubing shall be installed in accordance with the manufacturer's installation instructions and system design. The length of continuous tubing from a supply-and-return manifold shall not exceed the lengths specified by the manufacturer or, in the absence of manufacturer's specifications, the lengths specified in Table 1217.5. Actual loop lengths shall be determined by spacing, number of loops, flow rate, and pressure drop requirements, as specified in the system design.

    For the purpose of system balancing, each individual loop shall have a tag securely affixed to the manifold to indicate the length of the loop, and the room(s) and area(s) served.

    In a single-zone multiple-manifold installation, balanced flow through manifolds shall be as specified in Section 1215.4.

TABLE 1217.5
MAXIMUM LENGTH OF CONTINUOUS TUBING FROM A SUPPLY-AND-RETURN MANIFOLD ARRANGEMENT
NOMINAL TUBE SIZE
(inches)
MAXIMUM LOOP LENGTH
(feet)
14 125
516 200
38 250
12 300
58 400
34 500
1 750
For SI units: 1 inch = 25.4 mm, 1 foot = 304.8 mm
Where tubing is embedded in a concrete slab such tubes shall not be larger in outside dimension than one-third of the overall thickness of the slab and shall be spaced not less than three diameters on center. The top of the tubing shall be embedded in the slab not less than 2 inches (51 mm) below the surface.
Where embedded in or installed under a concrete slab, tubing shall be protected from damage at penetrations of the slab with a protective pipe sleeve. The space between the tubing and sleeve shall be sealed. The tubing at the location of an expansion joint in a concrete slab shall be encased in a protective pipe sleeve that covers the tubing not less than 12 inches (305 mm) on either side of the expansion joint or the tubing shall be installed below the slab.
Where a poured concrete radiant floor system is installed in contact with the soil, not less than R-5 insulation shall be installed and shall be placed between the soil and the concrete; extend to the outside edges of the concrete; and be placed on all slab edges.

    Where a poured concrete radiant floor system is installed on grade, not less than R-5 insulation shall be installed and placed on vertical slab edges.

    Where a poured concrete radiant floor system is installed within a habitable space above and below, the total R-value of the floor system below the concrete slab shall be more than the total R-value of the material lying above the concrete slab and the floor system shall have not less than a R-3 value.
Where tubing is installed below a subfloor, the tube spacing shall be in accordance with the system design and joist space limitations.

    Where tubing is installed above or in the subfloor, the tube spacing shall not exceed 12 inches (305 mm) center-to-center for living areas.

    Where tubing is installed in the joist cavity, the cavity shall be insulated with not less than R-12 material.

    An air space of not less than 2 inches (51 mm) shall be maintained between the top of the insulation and the underside of the floor unless a conductive plate is installed.

    Where tubing is installed above or in the subfloor and not embedded in concrete, the floor assembly shall be insulated with not less than R-12 material below the tubing.
Where piping is installed in the wall stud cavity or the ceiling joist cavity, the cavity shall be insulated with not less than R-12 material. The insulation shall be installed in such a manner as to prevent heating or cooling loss from the space intended to be controlled.

    An air space of not less than 2 inches (51 mm) shall be maintained between the insulation and the interior surface of the panel unless a conductive plate is installed.
Radiant heating and cooling panels shall be installed in accordance with the manufacturer's installation instructions and shall be listed for the application.
Clearances for electric heating panels or between outlets, junction boxes, mounting luminaries, ventilating, or other openings shall comply with NFPA 70.
Radiant panels attached to wood, steel, masonry, or concrete framing members shall be fastened by means of anchors, bolts, or approved expansion screws of sufficient size and anchorage to support the loads applied. In high moisture areas, panels shall be installed with corrosion-resistant fasteners. Piping systems shall be designed for thermal expansion to prevent the load being transmitted to the panel.
Systems utilizing heat exchangers shall protect the potable water system from being contaminated by the heat transfer medium. Systems that incorporate a single-wall heat exchanger to separate potable water from the heat-transfer fluid shall meet the following requirements:
  1. Heat transfer medium is either potable water or contains fluids recognized as safe by the Food and Drug Administration (FDA) as food grade.
  2. A tag or label shall be securely affixed to the heat source with the word, "CAUTION" and the following statements:

    1. The heat transfer medium shall be water or other nontoxic fluid recognized as safe by the FDA.
    2. The maximum operating pressure of the heat exchanger shall not exceed the maximum operating pressure of the potable water supply.
  3. The word "CAUTION" and the statements listed above shall have an uppercase height of not less than 0.120 of an inch (3.048 mm). The vertical spacing between lines of type shall be not less than 0.046 of an inch (1.168 mm). Lowercase letters shall be not less than compatible with the uppercase letter size specification.
Systems that do not comply with the requirements for a single-wall heat exchanger shall install a double wall heat exchanger. Double-wall heat exchangers shall separate the potable water from the heat transfer medium by providing a space between the two walls that are vented to the atmosphere.
Domestic hot-water heat exchangers, whether internal or external to the heating appliance, shall be permitted to be used to heat water in domestic hot-water storage tanks. Tanks used to store hot water shall be listed for the intended use and constructed in accordance with nationally recognized standards. A pressure- and temperature-relief valve with a set pressure not exceeding 150 percent of the maximum operating pressure of the system, and at a temperature of 210°F (99°C), shall be installed on the storage tank.

    Where the normal operating temperature of the boiler or dual-purpose water heater that provides heat input for domestic hot water exceeds 140°F (60°C), a thermostatically controlled mixing valve as specified in Section 1207.3.1 shall be installed to limit the water supplied to the potable hot water system to a temperature of 140°F (60°C) or less. The potability of the water shall be maintained throughout the system.
Additional heating loads shall be sized in accordance with one of the following methods and the required additional capacity shall be added to the primary heat source.
  1. Methods included in this chapter.
  2. Other approved engineering methods acceptable to the Authority Having Jurisdiction.
  3. Sizing guidelines included in the manufacturer's instructions.
    Where an auxiliary system is deemed to be in use only in seasons other than winter, it shall not be required to be combined with the space heating requirement in the winter. The heat source shall be sized to the level of the highest total seasonal load.
Where auxiliary systems contain chemical additives, corrosive fluids, or both not intended or designed for use in the primary system, a double wall heat exchanger shall be used in accordance with Section 1218.1. The chemical additives in the auxiliary systems shall be compatible with auxiliary system components and accepted for use by the heat exchanger manufacturer.
An automatic thermostatically operating control device that controls the supply hydronic solution temperature to the snow melt area shall be installed in the system. A means shall be provided to prevent low return hydronic solution temperature, as specified in Section 1213.5. Snow melt auxiliary systems shall be protected from freezing with an approved hydronic solution. The circulating heat transfer fluid shall be a mixture of propylene glycol or ethylene glycol, and water. Automotive antifreeze shall not be used.
Snow melt tubing shall be installed in accordance with the manufacturer's installation instructions and with the tubing layout and spacing as specified in the system design. Except for distribution mains, tube spacing that is shown in the design as center-to-center and the individual loop lengths shall be installed with a variance of not more than ±10 percent from the design.

    The length of continuous tubing from a supply-and-return manifold arrangement shall not exceed the lengths specified by the manufacturer's installation instructions and system design or, in the absence of manufacturer's specifications, the lengths specified in Table 1220.3.1. Actual loop lengths shall be determined by spacing, flow rate, temperature, and pressure drop, as specified in the system design.

TABLE 1220.3.1
LOOP LENGTHS FOR SNOW MELT SYSTEMS1,2
SIZE
(inches)
AVERAGE ACTIVE LOOP
(feet)
TOTAL LOOP
(feet)
PE-RT and PEX Tubing
58 225 250
34 300 325
1 450 475
Copper Tubing3
12 - 140
34 - 280
For SI units: 1 inch = 25.4 mm, 1 foot = 304.8 mm

Notes:
1   The total PE-RT and PEX loop lengths consist of two separate sections, the active loop and the leader length. The active loop is installed within the heated slab. The leader length is the total distance to and from the manifold and heated slab, including any vertical distances.
2   The manifolds shall be installed as close to the snow melt area as possible.
3   In concrete use minimum Type L copper water tubing. In bituminous pavement use a Type K copper water tubing.
Where tubes are embedded in a concrete slab, such tubes shall not be larger in outside dimension than one-third of the overall thickness of the slab and shall be spaced not less than three diameters on center. The top of the tubing shall be embedded in the slab not less than 2 inches (51 mm) below the surface.
Where embedded in or installed under a concrete slab, tubing shall be protected from damage at penetrations of the slab with a protective pipe sleeve. The space between the tubing and sleeve shall be sealed. The tubing at the location of a joint in a concrete slab shall be encased in a protective pipe sleeve that covers the tubing not less than 12 inches (305 mm) on either side of the joint or the tubing shall be installed below the slab.
A solid foundation shall be prepared before the tubing is installed. Compaction shall be used for slabs, sidewalks, and driveways.
Where a poured concrete snow melt system is installed in contact with the soil, insulation that has a R-5 value shall be placed between the concrete and the compacted grade; extend as close as practical to the outside edges of the concrete; and be placed on vertical slab edges that are in contact with plants or landscaping.
Testing of auxiliary systems shall be in accordance with Section 1205.2.
Hydronic makeup air units that are affected by freezing shall be protected against freezing by a hydronic solution or a method approved by the Authority Having Jurisdiction.
Piping, fittings, and connections shall be installed in accordance with the conditions of their approval.
Piping for heating or cooling panels embedded in concrete shall be steel pipe, Type L copper tubing or plastic pipe or tubing rated at not less than 100 psi at 180°F (689 kPa at 82°C). Joints of pipe or tubing that are embedded in a portion of the building, such as concrete or plaster shall be installed in accordance with the requirements of Section 1221.2.1 through Section 1221.2.3.
Steel pipe shall be welded by electrical are or oxygen/acetylene method.
Copper tubing shall be joined by brazing with filler metals having a melting point not less than 1000°F (538°C).
Plastic pipe and tubing shall be installed in continuous lengths or shall be joined by heat fusion method.
Piping to be embedded in concrete shall be pressure tested prior to pouring concrete. During the pour, the pipe shall maintain the test pressure of not less than one and one-half times the operating pressure but not less than 100 psi (689 kPa). During freezing or the possibility of freezing conditions, testing shall be done with air where permitted by the manufacturer.
Hydronic piping systems shall be installed to permit the system to be drained. The system shall drain by indirect waste in accordance with Section 1001.4. Embedded piping underground or under floors is not required to be designed for draining the system.
Condensate drains from dehumidifying coils shall be constructed and sloped for condensate removal. Such drains shall be installed in accordance with Section 310.0.
Hydronic piping where the exterior temperature exceeds 250°F (121°C) shall have a clearance of not less 1 inch (25.4 mm) to combustible materials.
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