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There are no amended sections in this chapter.
The provisions of this chapter shall govern the construction, installation, alteration and repair of hydronic piping systems. This chapter shall apply to hydronic piping systems that are part of heating, ventilation and air-conditioning systems. Such piping systems shall include steam, hot water, chilled water, condenser water, cooling coil condensate drain, steam condensate and ground-source heat pump loop systems. Potable cold and hot water distribution systems shall be installed in accordance with the New York City Plumbing Code.
Piping material, other than those contained within this section and conforming with the ASTM standards listed within this chapter, shall be of an approved type.
Exception:
Embedded piping regulated by Section 1209, and ground-source heat pump loop
systems regulated by Section 1210.
Reused pipe, fittings, valves or other materials shall be clean and free of foreign materials.
Materials shall be rated for the operating temperature and pressure of the hydronic system. Materials shall be suitable for the type of fluid in the hydronic system.
Hydronic pipe shall conform to the standards listed in Table 1202.4. The exterior of the pipe shall be protected from corrosion and degradation.
| MATERIAL | STANDARD (see Chapter 15) |
| Acrylonitrile butadiene styrene (ABS) plastic pipe | ASTM D 1527; ASTM F 2806 |
| Chlorinated polyvinyl chloride (CPVC) plastic pipe | ASTM D 2846; ASTM F 441; ASTM F 442 |
| Copper, brass, or copper-alloy pipe | ASTM B 42; ASTM B 43; ASTM B 302 |
| Copper, brass, or copper-alloy tube (Type K, L or M) | ASTM B 75; ASTM B 88; ASTM B 135; ASTM B 251 |
| Cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pressure pipe | ASTM F 1281; CSA B137.10 |
| Cross-linked polyethylene (PEX) tubing | ASTM F 876; ASTM F 877 |
| Ductile iron pipe | AWWA C115/A21.15; AWWA C151/A21.51 |
| Polyethylene/aluminum/polyethylene (PE-AL-PE) pressure pipe |
ASTM F 1282; CSA B137.9 |
| Polypropylene (PP) plastic pipe | ASTM F 2389 |
| Polyvinyl chloride (PVC) plastic pipe | ASTM D 1785; ASTM D 2241 |
| Raised temperature polyethylene (PE-RT) | ASTM F 2623; ASTM F 2769 |
| Steel pipe | ASTM A 53/A 53M; ASTM A 106 |
| Steel tubing | ASTM A 254 |
Hydronic pipe fittings shall conform to the respective pipe standards or to the standards listed in Table 1202.5.
| MATERIAL | STANDARD (see Chapter 15) |
| Copper, brass, and copper alloys | ASME B16.15; ASME B16.18; ASME B16.22; ASME B16.24; ASME B16.26; ASME B16.51; ASTM F 1974 |
|
Ductile iron and gray iron
|
ANSI/AWWA C110/A21.10; AWWA C153/A21.53; ASTM A 126; ASTM A 395; ASTM A 536; ASTM F 1476; ASTM F 1548
|
| Malleable iron | ASME B16.3 |
|
PE-RT fittings
|
ASTM F 1807; ASTM F 2098; ASTM F 2159; ASTM F 2735; ASTM F 2769
|
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PEX fittings
|
ASTM F 877; ASTM F 1807; ASTM F 2159
|
| Plastic | ASTM D 2466; ASTM D 2467; ASTM F 438; ASTM F 439; ASTM F 877; ASTM F 2389; ASTM F 2735 |
| Steel | ASME B16.5; ASME B16.9; ASME B16.11; ASME B16.28; ASTM A 53/A 53M; ASTM A 106; ASTM A 234; ASTM A 420; ASTM A 536; ASTM A 395; ASTM F 1476; ASTM F 1548 |
Valves shall be constructed of materials that are compatible with the type of piping material and fluids in the system. Valves shall be rated for the temperatures and pressures of the systems in which the valves are installed.
Flexible connectors, expansion and vibration control devices and fittings, when used, shall protect the components of the hydronic system from damage caused by expansion, contraction, transverse movement, angular deflection and vibration, shall be rated for the temperatures and pressures of the systems in which the devices are installed, and shall be compatible with the fluid and all materials provided.
Joints and connections, other than those contained in Section 1203 and conforming to the ASTM standards listed in Section 1203, shall be of an approved type. Joints and connections shall be tight for the pressure of the hydronic system.
Joints between different piping materials shall be rated for the temperatures and pressures of the systems in which the devices are installed and shall be compatible with the fluid and all materials provided.
Joints between dissimilar metallic piping materials shall be provided to protect against galvanic corrosion. Such joints shall be made with dielectric fittings conforming to ANSI B16.39 or ASTM F 492, as applicable, shall be rated for the temperatures and pressures of the systems in which the devices are installed and shall be compatible with the fluid and all materials provided.
Exception:
Dielectric fittings shall not be required for joints between dissimilar metal piping
used within heat transfer appliances or equipment when such joints are provided by the
appliance or equipment manufacturer, and such appliance or equipment is connected with
isolation valves that are accessible.
Where required by Sections 1203.4 through 1203.14, the preparation and installation of brazed, mechanical, soldered, solvent-cemented, threaded and welded joints shall comply with Sections 1203.3.1 through 1203.3.8.
Mechanical joints shall be installed in accordance with the manufacturer's instructions.
Joint surfaces shall be cleaned. A flux conforming to ASTM B 813 shall be applied. The joint shall be soldered with a solder conforming to ASTM B 32.
Joint surfaces shall be clean and free of moisture. A primer, compatible with both the piping material and the cement shall be applied to pipe-joint surfaces, in accordance with the manufacturer's requirements. Joints shall be made while the cement is wet. Solvent cement conforming to the following standards shall be applied to all joint surfaces:
- ASTM D 2235 for ABS joints.
- ASTM F 493 for CPVC joints.
- ASTM D 2564 for PVC joints.
Threads shall conform to ASME B 1.20.1. 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 compatible for application on the piping material and fluid.
All joints shall be welded with a welding procedure developed and qualified in accordance with the ASME Boiler and Pressure Vessel Code, Section IX (Welding and Brazing Qualifications) or in accordance with AWS B2.1 Specifications for Welding Procedure and Performance Qualification.
Grooved and shouldered mechanical joints shall conform to the requirements of ASTM F 1476 and shall be installed in accordance with the manufacturer's instructions.
Mechanically extracted outlets shall have a height not less than three times the thickness of the branch tube wall.
Branch tubes shall not restrict the flow in the run tube. A dimple/depth stop shall be formed in the branch tube to ensure that penetration into the outlet is of the correct depth. For inspection purposes, a second dimple shall be placed 1/4 inch (6.4 mm) above the first dimple. Dimples shall be aligned with the tube run.
Mechanically formed tee fittings shall be brazed in accordance with Section 1203.3.1.
Joints between ABS plastic pipe or fittings shall be solvent-cemented or threaded joints conforming to Section 1203.3.
Joints between brass pipe or fittings shall be brazed, mechanical, threaded or welded joints conforming to Section 1203.3.
Joints between brass tubing or fittings shall be brazed, mechanical or soldered joints conforming to Section 1203.3.
Joints between copper or copper-alloy pipe or fittings shall be brazed, mechanical, soldered, threaded or welded joints conforming to Section 1203.3.
Joints between copper or copper-alloy tubing or fittings shall be brazed, mechanical or soldered joints conforming to Section 1203.3, flared joints conforming to Section 1203.8.1 or push-fit joints conforming to Section 1203.8.2.
Flared joints shall be made by a tool designed for that operation.
Push-fit joints shall be installed in accordance with the manufacturer's instructions.
Joints between CPVC plastic pipe or fittings shall be solvent-cemented or threaded joints conforming to Section 1203.3.
Joints between cross-linked polyethylene plastic tubing and fittings shall conform to Sections 1203.11.1 and 1203.11.2. Mechanical joints shall conform to Section 1203.3.
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.
Soldering on the metal portion of the system shall be performed not less than 18 inches (457.2 mm) from a plastic-to-metal adapter in the same water line.
Joints between PVC plastic pipe and fittings shall be solvent-cemented or threaded joints conforming to Section 1203.3.
Joints between steel pipe or fittings shall be mechanical, threaded or welded joints conforming to Section 1203.3.
Joints between steel tubing or fittings shall be mechanical or welded joints conforming to Section 1203.3.
Heat-fusion joints for polypropylene (PP) pipe and tubing joints shall be installed with socket-type heat-fused polypropylene fittings, electro-fusion 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 F 2389.
Mechanical and compression sleeve joints shall be installed in accordance with the manufacturer's instructions.
Joints between raised temperature polyethylene tubing and fittings shall conform to Sections 1203.16.1 and 1203.16.2. Mechanical joints shall conform to Section 1203.3.
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.
Joints between polyethylene/aluminum/polyethylene pressure pipe and fittings shall conform to Sections 1203.17.1 and 1203.17.2. Mechanical joints shall comply with Section 1203.3.
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.
Joints between cross-linked polyethylene/aluminum/cross-linked polyethylene pressure pipe and fittings shall conform to Sections 1203.18.1 and 1203.18.2. Mechanical joints shall comply with Section 1203.3.
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.
Pipe insulation installed in buildings shall conform to the requirements of the New York City Energy Conservation Code, shall be tested in accordance with ASTM E 84 or UL 723, using the specimen preparation and mounting procedures of ASTM E 2231; and shall have a maximum flame spread index of 25 and a smoke-developed index not exceeding 450. Insulation installed in an air plenum shall comply with Section 602.2.1.
Hydronic piping shall be insulated to the thickness required by the New York City Energy Conservation Code.
Shutoff valves shall be installed on the supply and return side of a heat exchanger.
Exception:
Shutoff valves shall not be required where heat exchangers are integral with a boiler; or are a component of a manufacturer's boiler and heat exchanger packaged unit and are capable of being isolated from the hydronic system by the supply and return valves required by Section 1005.1.
Shutoff valves shall be installed on the building supply and return of central utility systems, and district heating and cooling systems.
Shutoff valves shall be installed on the connection to any 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 hydronic system such as pumps, air separators, metering devices and similar equipment.
Lockable shutoff valves shall be installed at connections to all expansion tanks. Valves shall be locked in the open position.
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. The valve shall be installed in accordance with Section 1006.
Piping, valves, fittings and connections shall be installed in accordance with the conditions of approval.
Hydronic piping systems shall be designed and installed to permit the system to be drained. Where the system drains to the plumbing drainage system, the installation shall conform to the requirements of the New York City Plumbing Code.
Exception: The buried portions of systems embedded underground.
The potable water system shall be protected from backflow in accordance with the New York City Plumbing Code.
Openings for pipe penetrations in walls, floors or 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 New York City Building Code.
A pipe in a hydronic piping system in which the exterior temperature exceeds 250°F (121.1°C) shall have a minimum clearance of 1 inch (25.4 mm) to combustible materials.
The flow velocity of the hydronic piping system shall be controlled to reduce the possibility of water hammer. Where a quick-closing valve creates water hammer, an engineered water-hammer arrestor shall be installed. The arrestor shall be located within a range as specified by the manufacturer of the quick-closing valve.
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 flood hazard areas shall comply with Appendix G of the New York City Building Code.
Pipe shall be supported in accordance with Section 305. Seismic supports shall be provided where required by the New York City Building Code.
Provisions shall be made to prevent the formation of condensation on the exterior of piping.
The flash point of transfer fluid in a hydronic piping system shall be not less than 50°F (10°C) above the maximum system operating temperature.
The transfer fluid shall be compatible with the makeup water supplied to the system.
Hydronic piping systems other than ground-source heat pump loop systems shall be tested hydrostatically at one and one half times the system design operating pressure, but not less than 100 psi (689 kPa). The duration of each test shall be not less than 2 hours. Ground-source heat pump loop systems shall be tested in accordance with Section 1210.10.
Embedded piping shall be plastic pipe or tubing, in accordance with Section 1202, rated at 100 psi (689.5 kPa) at 180°F (82.2°C).
Joints of other piping in cavities or running exposed shall be joined in accordance with manufacturer's instructions and related sections of this code.
Radiant floor heating systems shall be provided with a thermal barrier in accordance with Sections 1209.5.1 through 1209.5.4.
Exception: Insulation shall not be required in engineered systems where it can be demonstrated that the insulation will decrease the efficiency or have a negative effect on the installation.
In suspended floor applications, insulation shall be installed in the joist bay cavity serving the heating space above and shall consist of materials having a minimum R-value of 11.
A thermal break shall be provided consisting of asphalt expansion joint materials or similar insulating materials at a point where a heated slab meets a foundation wall or other conductive slab.
Insulating materials utilized in thermal barriers shall be installed such that the manufacturer's R-value mark is readily observable upon inspection.
Pipe and tubing shall be rated for the operating temperature and pressure of
the ground-source heat pump loop system. Fittings shall be suitable for the pressure applications and
recommended by the manufacturer for installation with the pipe and tubing material installed. Where
used underground, materials shall be suitable for burial.
Ground-source heat pump ground-loop pipe and tubing shall conform to the standards listed in Table 1210.4.
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MATERIAL
|
STANDARD (see Chapter 15)
|
| Chlorinated polyvinyl chloride (CPVC) | ASTM D 2846; ASTM F 441; ASTM F 442 |
| Cross-linked polyethylene (PEX) | ASTM F 876; ASTM F 877; CSA B137.5 |
| Polyethylene/aluminum/polyethylene (PE-AL-PE) pressure pipe | ASTM F 1282; CSA B137.9 |
| High-density polyethylene (HDPE) | ASTM D 2737; ASTM D 3035; ASTM F 714; AWWA C901; CSA B137.1; CSA C448; NSF 358-1 |
| Polypropylene (PP-R) | ASTM F 2389; CSA B137.11 |
| Polyvinyl chloride (PVC) | ASTM D 1785; ASTM D 2241 |
| Raised temperature polyethylene (PE-RT) | ASTM F 2623 |
Ground-source heat pump pipe fittings shall conform to the standards listed in Table 1210.5 and, if installed underground, shall be suitable for burial.
|
PIPE MATERIAL
|
STANDARD (see Chapter 15)
|
| Chlorinated polyvinyl chloride (CPVC) | ASTM D 2846; ASTM F 437; ASTM F 438; ASTM F 439; CSA B137.6 |
| Cross-linked polyethylene (PEX) | ASTM F 877; ASTM F 1807; ASTM F 1960; ASTM F 2080; ASTM F 2159; ASTM F 2434; CSA B137.5 |
| Polyethylene/aluminum/polyethylene (PE-AL-PE) | ASTM F 1282; ASTM F 2434; CSA B137.9 |
| High Density Polyethylene (HDPE) | ASTM D 2683; ASTM D 3261; ASTM F 1055; CSA B137.1; CSA C448; NSF 358-1 |
| Polypropylene (PP-R) | ASTM F 2389; CSA B137.11 |
| Polyvinyl chloride (PVC) | ASTM D 2464; ASTM D 2466; ASTM D 2467; CSA B137.2; CSA B137.3 |
| Raised temperature polyethylene (PE-RT) | ASTM D 3261; ASTM F 1807; ASTM F 2159; CSA B137.1 |
Joints and connections, other than those covered by Section 1210 and conforming
to the ASTM standards listed therein, shall be of an approved type. Joints and connections shall
be tight for the pressure of the ground-source loop system. Joints used underground shall be in
accordance with manufacturer's instructions for buried applications.
Joints between different piping materials
shall be made with transition fittings compatible with both materials and the fluid contained
within the system. Transition fittings must be used in accordance with manufacturer's
instructions.
Soldering on the metal portion of the system
shall be performed not less than 18 inches (457.2 mm) from a plastic-to-metal adapter in
the same water line.
Where required by Sections 1210.6.4 through
1210.6.6, the preparation and installation of mechanical and thermoplastic-welded joints shall
comply with Sections 1210.6.3.1 and 1210.6.3.2.
Mechanical joints shall be installed in accordance with the
manufacturer's instructions.
Joint surfaces for thermoplastic-welded joints
shall be cleaned by a procedure in accordance with the manufacturer's instructions. Joints
shall be welded in accordance with the manufacturer's instructions.
Joints between CPVC plastic pipe or fittings shall be solvent-cemented or threaded joints complying with Section 1203.3.
Joints between cross-linked
polyethylene plastic tubing and fittings shall comply with Sections 1210.6.5.1 and 1210.6.5.2.
Mechanical joints shall comply with Section 1210.6.3.
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.
Joints between polyethylene plastic pipe and tubing or fittings for ground-source heat pump
loop systems shall be heat fusion joints complying with Section 1210.6.6.1, electrofusion joints
complying with Section 1210.6.6.2, or stab-type insertion joints complying with Section
1210.6.6.3.
Joints shall be of the socket-fusion, saddle-fusion or butt-fusion type, joined in accordance with ASTM D 2657. Joint surfaces shall be clean and free from 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 D 2683 or ASTM D 3261.
Joints shall be of the electrofusion type. Joint surfaces
shall be clean and free from 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 F 1055.
Joint surfaces shall be clean and free from moisture.
Pipe ends shall be chamfered and inserted into the fittings to full depth. Fittings shall be
manufactured in accordance with ASTM F 1924.
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 F 2389.
Mechanical and compression
sleeve joints shall be installed in accordance with the manufacturer's instructions.
Joints between raised
temperature polyethylene tubing and fittings shall comply with Sections 1210.6.8.1 and
1210.6.8.2. Mechanical joints shall comply with Section 1210.6.3.
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.
Joints between PVC plastic pipe and fittings shall be solvent-cemented or threaded joints comply with Section 1203.3.
Shutoff valves shall be installed on the supply and return side of a
heat exchanger.
Exception:
Shutoff valves shall not be required where heat exchangers are integral with a
boiler; or are a component of a manufacturer's boiler and heat exchanger packaged unit
and are capable of being isolated from the hydronic system by the supply and return valves
required by Section 1005.1.
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 any 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. The valve shall be installed in accordance with
Section 1006.
Piping, valves, fittings, and connections shall be installed in accordance with
the conditions of approval.
Where ground-source heat pump ground-loop systems
have a connection to a potable water supply, the potable water system shall be protected from
backflow in accordance with the New York City Plumbing Code.
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 New York City Building Code.
A pipe in a ground-source heat pump piping system
having an exterior surface temperature exceeding 250°F (121.1°C) shall have a minimum
clearance of 1 inch (25.4 mm) from combustible materials.
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 305.
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 (689.5 kPa) for 15 minutes, in which time there shall not
be 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. If 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. Embedded piping shall comply with Section 1209.
The provisions of this section shall apply to high-pressure steam piping system, which is defined as a system operating at a steam pressure of more than 15 psi (103.4 kPa), and high temperature water intended for operation at pressures in excess of 160 psi (1103.2 kPa) and temperatures in excess of 250°F (121.1°C). For purposes of this section, loops, bends or offsets of the piping shall not be considered expansion joints.
For purposes of this section, the replacement of existing steam piping systems, the installation of a new system in existing buildings, as well as installations in buildings hereafter constructed, shall be considered to be new high-pressure steam piping systems. The following requirements are applicable:
The design of new steam piping systems shall be conducted as follows:
- The system shall be designed by an engineer. An application and plans shall be filed and the approval of the department obtained. The plans and application shall contain, but not be limited to, the following information:
- Size and location of all steam piping.
- The operating pressures and temperatures.
- The location, type, specifications and details of all expansion joints.
- The design, size, material and location of all anchors, guides and auxiliary steel, and the stresses thereon.
- Systems using utility street steam shall be designed for a pressure of 200 psig (1379 kPa) and 413°F (211.7°C) up to and including the steam pressure reducing valve or valves which reduce the pressure of 90 psig (620.5 kPa) or below. For steam pressures between 90 psig (620.5 kPa) and 16 psig (110.3 kPa), the system shall be designed for 125 psig (861.8 kPa).
- Steam distribution systems utilizing pressure reducing valves.
- Safety Shutoff Valves (SSO) to protect downstream piping from overpressure shall be allowed in lieu of a safety relief valve vented to the outdoors as required by Section 1006.6.
- SSO shall be designed to automatically close at or below the design pressure of the downstream piping system that is being protected, to provide positive shutoff against full upstream pressure. Manual reset shall be required to reopen the SSO.
- SSO shall be designed in accordance with the Steam Distribution Utility System requirements of the utility company having jurisdiction and ASME B31.1.
- Bellows expansion joints shall not be utilized on high pressure steam piping.
The installation of new steam piping systems shall be conducted as follows:
- Installations, including any welding, shall be subject to special inspection.
- Welders shall be qualified for all required pipe sizes, wall thicknesses and positions in accordance with the ASME Boiler and Pressure Vessel Code, Section IX. Requalification is required every five years or sooner if the commissioner has a specific reason to doubt a welder's ability to make acceptable welds.
- Welder qualification testing shall be performed by an approved agency listed with the department, and the inspector witnessing the test shall be an authorized AWS Certified Welding Inspector. If the testing is by radiography, the test specimen shall be evaluated by personnel having a minimum radiography qualification of Level II in accordance with the ASNT, Document No. SNT-TC-1A, Supplement A. A successful radiographic test of a production weld made within the 6 months prior to requalification may be considered as an acceptable requalification test.
- Copies of the certified welder qualification reports shall be maintained by the responsible welding agency and the company performing the welding, and shall be made available upon request to the department.
- No reports from any welding inspection agency shall be accepted unless such agency has first requested and obtained approval from the department in accordance with rules of the department.
- Pipe welding shall conform to the following:
- All piping over 2 inches (50.8 mm) shall be butt-welded. Piping 2 inches (50.8 mm) and under may be socket-welded or threaded, providing Schedule 80 piping is utilized.
- Threaded piping may continue to be used for existing construction in size of 6 inches (152.4 mm) and under.
- Where welding is not feasible, the commissioner may allow an acceptable alternative.
- Radiographic examination, when required, shall be performed on butt-welds in accordance with ASME B31.1 based on the piping system design pressure and shall be as follows:
Piping System Design Pressure Percentage 90 psig (620.5 kPa) or below Not Required 91 psig (627.4 kPa) to
150 psig (1034.2 kPa)10 at Random Over 150 psig (1034.2 kPa) 100
However, if, in the opinion of the engineer responsible for special inspection, radiographic examination is not required for piping at pressure between 90 psig (620.5 kPa) and 150 psig (1034.2 kPa), the engineer shall so specify in writing, and the final report on the installation may omit the foregoing, and be predicated on all of the other requirements noted in this section, and a hydrostatic test.
The commissioner, where deemed necessary, shall require the replacement or relocation of any expansion joints, guides or anchors. The commissioner shall cause the expansion joints in potentially hazardous locations, such as those that are located adjacent to tenant occupied spaces, to be relocated, unless means exist or are provided for eliminating the hazard.
Existing steam piping systems shall be in accordance with Sections 1211.3.1 through 1211.3.2. Upon the completion of a new high-pressure steam piping system and department approval of same, the rules relating to maintenance requirements and the keeping of records for existing high-pressure steam piping systems shall apply.
Expansion joints, anchorage and guides shall be inspected as follows:
- Expansion joints shall be visually inspected monthly.
- The anchorage and guides shall be visually inspected annually. Exposure of the structural attachments to the buildings of the anchorages or guides shall not be required.
- A record of such inspections shall be kept by the person in charge of the mechanical equipment of the building or other qualified person designated by the owner and acceptable to the commissioner. The records shall be available at the premises and subject to inspection by the commissioner.
No joint, anchorage or guides shall be repaired, replaced or relocated without a work permit issued by the department. The application for the permit shall contain all pertinent information and shall be filed by an engineer knowledgeable as to high-pressure steam piping systems. The engineer shall be responsible for the special inspection of the proposed work in accordance with the approved application. This provision shall not apply to the repacking of a slip or ball joint; however, records of such repacking shall be kept in the inspection records as provided in Section 1211.3.1, Item 3. When, in the opinion of the engineer, the requirement for prior department approval would create an imminent health or safety hazard, the engineer may permit the work to proceed without prior approval. In such cases, the engineer shall, prior to the repair, replacement or relocation, notify by telephone the borough commissioner of the borough in which the building is located; and, if the emergency occurs at other than normal working hours, he or she shall notify the department in a manner prescribed by the commissioner. This shall be followed by the filing of the application for department approval as specified in Section 28-105.4.1 of the Administrative Code.
