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Hydronic Piping (18-28-1200 et seq.)

Municipal Code of Chicago tit. 18, ch. 18-28, art. XII
in effect

Municipal Code of Chicago § 18-28-1201.1 Scope.

18-28-1201.1 Scope. The provisions of this article shall govern the construction, installation, alteration and repair of hydronic piping systems. This chapter shall apply to hydronic piping systems that are parts of heating, ventilation and air-conditioning systems. Such piping systems shall include steam, hot water, chilled water, steam condensate and ground source heat pump loop systems. Potable cold and hot water distribution systems shall be installed in accordance with the Chicago Plumbing Code. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 1)

Municipal Code of Chicago § 18-28-1202.2 Used materials.

18-28-1202.2 Used materials. Reused pipe, fittings, valves or other materials shall be clean and free of foreign materials and shall be approved by the Building Commissioner for reuse. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 2)

Municipal Code of Chicago § 18-28-1202.3 Material rating.

18-28-1202.3 Material rating. 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.

Municipal Code of Chicago § 18-28-1202.4 Piping materials standards.

18-28-1202.4 Piping materials standards. Hydronic pipe shall conform to the standards listed in Table 18-28-1202.4. The exterior of the pipe shall be protected from corrosion and degradation. Table 18-28-1202.4 Hydronic Pipe Material | Standard (see Chapter 16) Material | Standard (see Chapter 16) Acrylonirile butadiene styrene (ABS) plastic pipe | ASTM D 1527; ASTM D 2282 Brass pipe | ASTM B 43 Brass tubing | ASTM B 135 Copper or copper- alloy pipe | ASTM B 42; ASTM B 302 Copper or copper- alloy tube (Type K, L, or M) | ASTM B 75; ASTM B 88; ASTM B 251 Chlorinated polyvinyl chloride (CPVC) plastic pipe | ASTM D 2846; ASTM F 441; ASTM F 442 Cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pressure pipe | CSA CAN/CSA-B-137.10 Cross-linked polyethlene (PEX) tubing | ASTM F 876; ASTM F 877 Lead pipe | FS WW-P 325B Polybutylene (PB) plastic pipe and tubing | ASTM D 3309 Polyvinyl chloride (PVC) plastic pipe | ASTM D 1785; ASTM D 2241 Steel pipe | ASTM A 53; ASTM A 106 Steel tubing | ASTM A 254

Municipal Code of Chicago § 18-28-1202.5 Pipe fittings.

18-28-1202.5 Pipe fittings. Hydronic pipe fittings shall be approved for installation with the piping materials to be installed, and shall conform to the respective pipe standards or to the standards listed in Table 18-28-1202.5. Table 18-28-1202.5 Hydronic Pipe Fittings Material | Standard (see Article 15) Bronze | ASME B 16.24 Copper and copper alloys | ASME B 16.15; ASME B 16.18; ASME B 16.22; ASME B 16.23; ASME B 16.26; ASME B 16.29 Gray iron | ASTM A 126 Malleable iron | ASME B 16.3 Plastic | ASTM D 2466; ASTM D 2467; ASTM D 2468; ASTM F 438; ASTM F 439; ASTM F 877 Steel | ASME B 16.5; ASME B 16.9; ASME B 16.11; ASME B 16.28; ASTM A 420

Municipal Code of Chicago § 18-28-1202.6 Valves.

18-28-1202.6 Valves. 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.

Municipal Code of Chicago § 18-28-1202.7 Flexible connectors, expansion and vibration compensators.

18-28-1202.7 Flexible connectors, expansion and vibration compensators. Flexible connectors, expansion and vibration control devices and fittings shall be of an approved type.

Municipal Code of Chicago § 18-28-1203.1 Approval.

18-28-1203.1 Approval. Joints and connections shall be of an approved type. Joints and connections shall be tight for the pressure of the hydronic system.

Municipal Code of Chicago § 18-28-1203.1.1 Joints between different piping materials.

18-28-1203.1.1 Joints between different piping materials. Joints between different piping materials shall be made with approved adapter fittings. Joints between different metallic piping materials shall be made with approved dielectric fittings or brass converter fittings.

Municipal Code of Chicago § 18-28-1203.2 Preparation of pipe ends.

18-28-1203.2 Preparation of pipe ends. Pipe shall be cut square, reamed and chamfered, and shall be free of burrs and obstructions, Pipe ends shall have full-bore openings and shall not be undercut.

Municipal Code of Chicago § 18-28-1203.3 Joint preparation and installation.

18-28-1203.3 Joint preparation and installation. When required by Sections 18-28-1203.4 through 18-28-1203.14, the preparation and installation of brazed, mechanical, soldered, solvent-cemented, threaded and welded joints shall comply with Sections 18-28-1203.3 through 18-28-1203.3.7.

Municipal Code of Chicago § 18-28-1203.3.1 Brazed joints.

18-28-1203.3.1 Brazed joints. Joint surfaces shall be cleaned. An approved flux shall be applied where required. The joint shall be brazed with a filler metal conforming to AWS A5.8.

Municipal Code of Chicago § 18-28-1203.3.3 Soldered joints.

18-28-1203.3.3 Soldered joints. 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.

Municipal Code of Chicago § 18-28-1203.3.4 Solvent-cemented joints.

18-28-1203.3.4 Solvent-cemented joints. Joint surfaces shall be clean and free of moisture. An approved primer shall be applied to CPVC and to PVC pipe-joint surfaces. Joints shall be made while the cement is wet. Solvent cement conforming to the following standards shall be applied to all joint surfaces: 1. ASTM D 2235 for ABS joints. 2. ASTM F 493 for CPVC joints. 3. ASTM D 2564 for PVC joints. CPVC joints shall be made in accordance with ASTM D 2846.

Municipal Code of Chicago § 18-28-1203.3.5 Threaded joints.

18-28-1203.3.5 Threaded joints. Threads shall conform to 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.

Municipal Code of Chicago § 18-28-1203.3.7 Grooved and shouldered joints.

18-28-1203.3.7 Grooved and shouldered joints. Grooved and shouldered joints shall be approved and installed in accordance with the manufacturer's installation instructions.

Municipal Code of Chicago § 18-28-1203.4 ABS plastic pipe.

18-28-1203.4 ABS plastic pipe. Joints between ABS plastic pipe or fittings shall be solvent-cemented or threaded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.5 Brass pipe.

18-28-1203.5 Brass pipe. Joints between brass pipe or fittings shall be brazed, mechanical, threaded or welded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.7 Copper or copper-alloy pipe.

18-28-1203.7 Copper or copper-alloy pipe. Joints between copper or copper-alloy pipe or fittings shall be brazed, mechanical, soldered, threaded or welded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.8 Copper or copper-alloy tubing.

18-28-1203.8 Copper or copper-alloy tubing. Joints between copper or copper-alloy tubing or fittings shall be brazed, mechanical or soldered joints conforming to Section 18-28-1203.3 or flared joints conforming to Section 18-28-1203.8.1.

Municipal Code of Chicago § 18-28-1203.9 CPVC plastic pipe.

18-28-1203.9 CPVC plastic pipe. Joints between CPVC plastic pipe or fittings shall be solvent-cemented or threaded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.10 Polybutylene plastic pipe and tubing.

18-28-1203.10 Polybutylene plastic pipe and tubing. Joints between polybutylene plastic pipe and tubing or fittings shall be mechanical joints conforming to Section 18-28-1203.3 or heat-fusion joints conforming to Section 18-28-1203.10.1.

Municipal Code of Chicago § 18-28-1203.10.1 Heat-fusion joints.

18-28-1203.10.1 Heat-fusion joints. Joints shall be of the socket-fusion or butt-fusion type. 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. Joints shall be made in accordance with ASTM D 3309.

Municipal Code of Chicago § 18-28-1203.11 Cross-linked polyethylene (PEX) plastic tubing.

18-28-1203.11 Cross-linked polyethylene (PEX) plastic tubing. Joints between cross-linked polyethylene plastic tubing and fittings shall conform to Sections 18-28-1203.11.1 and 18-28-1203.11.2. Mechanical joints shall conform to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.11.1 Compression-type fittings.

18-28-1203.11.1 Compression-type fittings. If compression-type fittings include inserts and ferrules or O-rings, the fittings shall be installed without omitting the inserts and ferrules or O-rings.

Municipal Code of Chicago § 18-28-1203.11.2 Plastic-to-metal connections.

18-28-1203.11.2 Plastic-to-metal connections. Soldering on the metal portion of the system shall be performed at least 18 inches (457 mm) from a plasticto-metal adapter in the same water line.

Municipal Code of Chicago § 18-28-1203.12 PVC plastic pipe.

18-28-1203.12 PVC plastic pipe. Joints between PVC plastic pipe and fittings shall be solvent-cemented or threaded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1203.13 Steel pipe.

18-28-1203.13 Steel pipe. Joints between steel pipe or fittings shall be mechanical joints that are made with an approved elastomeric seal, or shall be threaded or welded joints conforming to Section 18-28-1203.3.

Municipal Code of Chicago § 18-28-1204.1 Insulation characteristics.

18-28-1204.1 Insulation characteristics. Pipe insulation installed in buildings shall conform to the requirements of the Chicago Energy Conservation Code, shall be tested in accordance with ASTM E 84 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 18-28-602.2.1. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 3)

Municipal Code of Chicago § 18-28-1204.2 Required thickness.

18-28-1204.2 Required thickness. Hydronic piping shall be insulated to the thickness required by the Chicago Energy Conservation Code. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 3)

Municipal Code of Chicago § 18-28-1205.1 Where required.

18-28-1205.1 Where required. Shut off valves shall be installed in hydronic piping systems in the locations indicated in Sections 18-28-1205.1.1 through 18-28-1205.1.6.

Municipal Code of Chicago § 18-28-1205.1.1 Heat exchangers.

18-28-1205.1.1 Heat exchangers. Shutoff valves shall be installed on the supply and return side of a heat exchanger. Exception: Shut off valves shall not be required when 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 18-28-1005.1.

Municipal Code of Chicago § 18-28-1205.1.5 Equipment and appliances.

18-28-1205.1.5 Equipment and appliances. 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.

Municipal Code of Chicago § 18-28-1205.2 Reduced pressure.

18-28-1205.2 Reduced pressure. 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 18-28-1006.

Municipal Code of Chicago § 18-28-1206.1.1 Prohibited tee applications.

18-28-1206.1.1 Prohibited tee applications. Fluid in the supply side of a hydronic system shall not enter a tee fitting through the branch opening.

Municipal Code of Chicago § 18-28-1206.2 System drain down.

18-28-1206.2 System drain down. 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 Chicago Plumbing Code. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 4)

Municipal Code of Chicago § 18-28-1206.3 Protection of potable water.

18-28-1206.3 Protection of potable water. The potable water system shall be protected from backflow in accordance with the Chicago Plumbing Code. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 4)

Municipal Code of Chicago § 18-28-1206.4 Pipe penetrations.

18-28-1206.4 Pipe penetrations. 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 Chicago Building Code. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 4)

Municipal Code of Chicago § 18-28-1206.5 Clearance to combustibles.

18-28-1206.5 Clearance to combustibles. A pipe in a hydronic piping system in which the exterior temperature exceeds 250°F (121°C) shall have a minimum clearance of 1 inch (25.4 mm) to combustible materials.

Municipal Code of Chicago § 18-28-1206.6 Contact with building material.

18-28-1206.6 Contact with building material. A hydronic piping system shall not be in direct contact with building materials that cause the piping material to degrade or corrode, or that interfere with the operation of the system.

Municipal Code of Chicago § 18-28-1206.7 Water hammer.

18-28-1206.7 Water hammer. 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 approved water-hammer arrester shall be installed. The arrester shall be located within a range as specified by the manufacturer of the quick-closing valve.

Municipal Code of Chicago § 18-28-1206.8 Steam piping pitch.

18-28-1206.8 Steam piping pitch. Steam piping shall be installed to drain to the boiler or the steam trap. Steam systems shall not have drip pockets that reduce the capacity of the steam piping.

Municipal Code of Chicago § 18-28-1206.9 Strains and stresses.

18-28-1206.9 Strains and stresses. 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.

Municipal Code of Chicago § 18-28-1206.9.1 Flood hazard.

18-28-1206.9.1 Flood hazard. Piping located in a flood-hazard zone or high-hazard zone shall be capable of resisting hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding to the base flood elevation.

Municipal Code of Chicago § 18-28-1207.1 Flash point.

18-28-1207.1 Flash point. The flash point of transfer fluid in a hydronic piping system shall be a minimum of 50°F (28°C) above the maximum system operating temperature.

Municipal Code of Chicago § 18-28-1208.1 General.

18-28-1208.1 General. Hydronic piping systems shall be tested hydrostatically at one and one-half times the maximum system design pressure, but not less than 100 psi (689 kPa).

Municipal Code of Chicago § 18-28-1209.1 Materials.

18-28-1209.1 Materials. Piping for heating panels shall be standard-weight steel pipe, Type L copper tubing, polybutylene or other approved plastic pipe or tubing rated at 100 psi (689 kPa) at 180°F (82°C).

Municipal Code of Chicago § 18-28-1209.2 Pressurizing during installation.

18-28-1209.2 Pressurizing during installation. 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.

Municipal Code of Chicago § 18-28-1209.3 Embedded joints.

18-28-1209.3 Embedded joints. Joints of pipe or tubing that are embedded in a portion of a building, such as a building's concrete or plaster, shall be in accordance with the requirements of Sections 18-28-1209.3.1 through 18-28-1209.3.3.

Municipal Code of Chicago § 18-28-1209.3.2 Copper tubing joints.

18-28-1209.3.2 Copper tubing joints. Copper tubing shall be joined by brazing with filler metals that have a melting point of at least 1,000°F (538°C).

Municipal Code of Chicago § 18-28-1209.3.3 Polybutylene joints.

18-28-1209.3.3 Polybutylene joints. Polybutylene pipe and tubing shall be installed in continuous lengths or shall be joined by heat fusion in accordance with Section 18-28-1203.10.1.

Municipal Code of Chicago § 18-28-1209.4 Not embedded related piping.

18-28-1209.4 Not embedded related piping. Joints of other piping located in cavities or running exposed shall be joined by approved methods in accordance with the manufacturer's installation instructions and related sections of this chapter. (Amend Coun. J. 9-14-21, p. 35949, Art. XII, § 5)
Source: City of Chicago, Municipal Code of Chicago (American Legal Publishing, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2688978Fetched: 10/24/2026

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