CMC · California Mechanical Code
Allowed joints and connection methods for hydronic piping
Hydronic pipe joints must be approved, gas‑ and watertight, and rated for system pressure. CPVC allows mechanical, solvent‑cement (with specified primer/colors and size limits), and threaded joints (Schedule 80, 50% pressure derating). CPVC/AL/CPVC follows similar solvent and mechanical rules. Copper requires brazing >1000°F or press‑connects with elastomeric O‑rings — always follow manufacturer instructions and the CMC §§ 1211.0–1211.5.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
Joints and connections for hydronic piping must be of an approved type, gas- and watertight, and designed for the system pressure; changes in direction must use fittings or formed bends. See § 1211.1 for the general rule and installation-over-manufacturer requirement.
The single most important rule: all joints must be an approved type and suitable for the system pressure — they must be installed per the manufacturer and the Mechanical Code. § 1211.1.
Requirements in detail
Summary — the CMC divides allowed joints by material. Below are the decision‑relevant allowed joint types and any mandatory installation limits called out in the controlling sections § 1211.0, § 1211.1, § 1211.3, § 1211.4, and § 1211.5 (citations follow each item).
- General: joints must be approved, gas- and watertight, suitable for system pressure, follow manufacturer instructions, and underground joints must be approved for burial (see § 1211.1).
CPVC (Chlorinated polyvinyl chloride) — key allowed connections
- Allowed joint types: mechanical (flanged, grooved, push‑fit), solvent‑cement, and threaded (with limits). § 1211.3.
- Solvent‑cement notes: primers and cements must meet ASTM requirements; primers that require use per ASTM F493 shall be orange (ASTM F656); listed one‑step cements that do not require primer (colors vary) are permitted for specified manufacturers/sizes. § 1211.3.
- Threading: a minimum of Schedule 80 CPVC may be threaded; when threaded the pressure rating is reduced by 50%. § 1211.3.
CPVC/AL/CPVC (sandwich) — allowed connections and colors
- Allowed joint types: mechanical (flanged, grooved, push‑fit) and solvent‑cement (ASTM F493). § 1211.4.
- Primer/cement color rules mirror CPVC: primer requiring ASTM F656 is orange; certain listed solvent cements not requiring primer (yellow, etc.) are allowed for specific pipe sizes per the section. § 1211.4.
Copper or copper‑alloy pipe and tubing — allowed connections
- Allowed joint types: brazed, pressed (press‑connect with elastomeric O‑ring), (where permitted) flared, and other approved methods — with detailed workmanship requirements. § 1211.5.
- Brazing: filler metal must have a liquid temperature above 1000°F (538°C); joint surfaces cleaned, tube cut square and reamed, and brazing filler in accordance with AWS A5.8 placed at the socket entry. § 1211.5.
- Pressed fittings: must have an elastomeric O‑ring, pipe fully inserted, cut square, chamfered and reamed; pressing tool per manufacturer. § 1211.5.
- Soldering: the code text for copper requires brazing for certain embedded/joining conditions and describes when solder is or is not permitted — follow § 1211.5 instructions. § 1211.5.
Installation & manufacturer instructions
- All joints and fittings shall be installed per the manufacturer’s installation instructions and be appropriate for the fluid, temperature and pressure of the hydronic system (general requirement: § 1211.1).
Quick reference table (decision‑relevant dimensions / values)
| Decision item | Value / limit | Code Reference |
|---|---|---|
| CPVC solvent‑cement sizes permitted without primer (listed) | ½ in — 2 in (ASTM D2846) and ½ in — 3 in (ASTM F442) where listed cement applies | § 1211.3 |
| CPVC threaded allowance | Minimum Schedule 80 allowed to be threaded; pressure rating reduced by 50% when threaded | § 1211.3 |
| CPVC primer color when required | Orange primer (ASTM F656) for cements requiring primer | § 1211.3 |
| CPVC/AL/CPVC solvent‑cement primer | Orange primer required where ASTM F493 requires primer; listed non‑primer cements (yellow etc.) allowed per sizes | § 1211.4 |
| Copper brazing minimum melt | > 1000°F (538°C); brazing filler meeting AWS A5.8 | § 1211.5 |
| Pressed fittings (copper) | Elastomeric O‑ring required; pipe must be cut square, chamfered, reamed and fully inserted; tool per manufacturer | § 1211.5 |
Exceptions & special cases
- Solvent‑cement limitations for embedded piping: when piping is to be embedded in concrete the CMC restricts solvent‑welded joints (see embedded piping rules — § 1221.2.3). If you will embed CPVC or other plastic piping, do NOT rely on solvent‑cement unless allowed by the embedded‑pipe rule.
- Manufacturer listings and ASTM standards: many plastic and composite pipe joints are permitted only when both the product and the joint method are listed and meet the ASTM/CSA/ASSE standards referenced in Table 1210.1 and their specific subsections — always check the referenced standard called out in the applicable §.
- Threaded CPVC: threaded CPVC is allowed but note the 50% pressure‑rating reduction and the requirement that threaded fittings be compatible (female CPVC threaded fittings with plastic male threads only where specified). § 1211.3.
Common mistakes
- Using solvent‑cement for piping that will be embedded in concrete. The CMC prohibits solvent cement in some embedded applications — check § 1221.2.3 before embedding.
- Assuming “push‑fit” equals universally approved: push‑fit connectors must be listed and comply with ASSE 1061 where required (CPVC push‑fit requirement in § 1211.3).
- Threading CPVC without accounting for the 50% pressure reduction and scheduling requirements — leads to undersized or unsafe joints. § 1211.3.
- Brazing/capillary work done without meeting the required brazing filler spec or without reaming and cleaning joint surfaces: brazed copper joints must meet the brazing temperature and workmanship specs in § 1211.5.
- Using press fittings on copper without ensuring an elastomeric O‑ring and manufacturer’s pressing tool instructions are followed — the code requires the O‑ring and full insertion per § 1211.5.
Worked example — concrete scenario
Scenario: You have a hydronic branch made of 1‑inch CPVC supply tubing and need to connect a 1‑inch socket fitting and a 1‑inch threaded isolation valve.
Step 1 — socket joint: The code permits solvent‑cement joints for CPVC and allows listed solvent cements that do not require primer for ½ in through 2 in pipe manufactured to ASTM D2846. A 1‑inch CPVC socket joint with the appropriate listed cement is therefore allowed. Install per manufacturer instructions and ASTM requirements. § 1211.3.
Step 2 — threaded valve: If you install a threaded connection on CPVC, ensure the pipe is at least Schedule 80 and acknowledge that the CMC requires the pressure rating be reduced by 50% at that threaded joint. Use compatible thread sealant that is insoluble in water and nontoxic; do not overtighten. § 1211.3.
Step 3 — verification: Confirm both fittings are listed for hydronic service, are rated for the system working pressure and temperature, and that installation follows the manufacturers’ instructions (general requirement § 1211.1).
Alternate example: Joining 1‑inch copper tube to a fitting intended to be brazed — select brazing alloy with melt point >1000°F (538°C) and use AWS A5.8 filler; ream and clean, then place filler at socket entry and braze per § 1211.5.
Related provisions
- § 1211.1 — General joints and connections (installation, watertight/gas tight, manufacturer instructions).
- § 1211.2 — Pipe bends (bend radii for PEX/PE) — relevant when bends are used instead of fittings.
- § 1211.10 — PE‑AL‑PE installation methods and crimp / compression details (useful for composite tubing).
- § 1211.16.2 — Plastic pipe to other materials (transition fittings and listed adapters).
- § 1221.2.3 — Plastics embedded in concrete — heat‑fusion required; solvent cement prohibited for embedded applications (important special case).
- Table references (Table 1210.1 and material standards): consult the materials table and referenced ASTM/CSA/ASSE standards for each material type.
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 1210.3 High relevance — show source text
1210.3 Hangers and Supports. Pipe and tubing shall be supported in accordance with Section 313.0. Equipment that is part of the piping system shall be provided with additional support in accordance with this code and manufacturer’s installation instructions. Radiant systems utilizing heat emission or transfer plates shall have a gap of at least ¼ inch (6.4 mm) between adjacent plates. 1210.4 Oxygen Diffusion Corrosion. PEX and PE-RT tubing in closed hydronic systems shall contain an oxygen barrier. 1210.4.1 Vented Closed-Loop Systems. All components installed in a vented closed-loop system shall be constructed of non-ferrous or other corrosion resistant
materials.
1210.4.2 Non-Oxygen Barrier Closed-Loop Sys- tems. All components installed in a non-oxygen barrier system shall be constructed of non-ferrous or other corrosion resistant materials.
1211.0 Joints and Connections.
1211.1 General. 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. Joints between pipe and fittings shall be installed in accordance with the manufacturer’s installation instructions. Joints used underground shall be of an approved type for buried applications in accordance with Section 1221.2.3.
1211.2 Pipe Bends. Pipe bends shall be formed in accordance with Section 1211.2.1 for PEX or Section 1211.2.2 for
PE.
1211.2.1 Crosslinked Polyethylene (PEX) Tubing. Crosslinked polyethylene (PEX) tubing bends shall have a bend radius of not less than eight times the outside diameter of the tubing or shall be in accordance with the manufacturer’s installation instructions.
1211.2.2 Polyethylene (PE) Plastic Pipe/Tubing. Polyethylene pipe and tubing bends shall have a bend radius in accordance with Table 1211.2.2. When a fitting or flange connection is present in the pipe bend, the minimum bend radius shall be one hundred times the pipe outside diameter (OD) for a distance of five times the pipe diameter on either side of the fitting location.
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1208.2 Mounting. The circulator or pump shall be installed in such a way that strain from the piping is not transferred to the circulator or pump housing. The circulator or pump shall be permitted to be directly connected to the piping, provided the piping is supported on each side of the circulator or pump. Where the installation of a circulator or pump will cause strain on the piping, the circulator or pump shall be installed on a mounting bracket or base plate or securely fastened to or supported by the structure with approved fastening devices. Where means for controlling vibration of a circulator or pump is required, an approved means for support and restraint shall be provided. 1208.3 Sizing. The selection and sizing of a circulator or pump 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 temperature, °F (°C) (4) Maximum working pressure, pounds per square inch (kPa) (5) Fluid type
1209.0 Expansion Tanks. **1209.1 General.
CMC § 1210.0 High relevance — show source text
1210.0 Materials . . . . . . . . . . . . . . . . . . . . 260
1210.1 Piping, Tubing, and Fittings . . . . . 260
1210.2 Expansion and Contraction . . . . . . 260
1210.3 Hangers and Supports . . . . . . . . . 260
1210.4 Oxygen Diffusion Corrosion . . . . . 260
1211.0 Joints and Connections . . . . . . . . 260
1211.1 General. . . . . . . . . . . . . . . . . . . . . 260
1211.2 Pipe Bends . . . . . . . . . . . . . . . . . . 260
Table 1210.1 Materials for Hydronic System Piping, Tubing, and Fittings . . . . . 261
Table 1211.2.2 Minimum Bend Radius
for PE Pipe Installed in Open Cut Trench . . . . . . . . . . . . . 262
1211.3 Chlorinated Polyvinyl Chloride (CPVC) Pipe . . . . . . . . . . . . . . . . . 262
1211.4 CPVC/AL/CPVC Plastic Pipe and Joints . . . . . . . . . . . . . . . . . . . 262
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1211.5 Copper or Copper Alloy Pipe and Tubing . . . . . . . . . . . . . . . . . . 262
1211.6 Crossed-Linked Polyethylene (PEX) Pipe . . . . . . . . . . . . . . . . . . 263
1211.7 Cross-Linked Polyethylene/ Aluminum/Cross-Linked
Polyethylene (PEX-AL-PEX) Pipe. . 263
1211.8 Ductile Iron Pipe . . . . . . . . . . . . . . 263
1211.9 Polyethylene (PE) Plastic Pipe/Tubing. . . . . . . . . . . . 263
1211.10 Polyethylene/Aluminum/ Polyethylene (PE-AL-PE) . . . . . . . 264
1211.11 Polyethylene of Raised Temperature (PE-RT). . . . . . . . . . 264
1211.12 Polypropylene (PP) Pipe. . . . . . . . 264
1211.13 Polyvinyl Chloride (PVC) Pipe . . . 264
1211.14 Steel Pipe and Tubing . . . . . . . . . 265
1211.15 Stainless Steel Pipe and Joints. . . 265
1211.16 Joints Between Various Materials. . 265
1212.0 Valves. . . . . . . . . . . . . . . . . . . . . . 265
1212.1 General. . . . . . . . . . . . . . . . . . . . . 265
1212.2 Where Required . . . . . . . . . . . . . . 265
1212.3 Heat Exchanger . . . . . . . . . . . . . . 265
1212.4 Pressure Vessels . . . . . . . . . . . . . 265
1212.5 Pressure Reducing Valves . . . . . . 265
CMC § 1208.0 High relevance — show source text
1208.0 Circulators and Pumps. 1208.1 General. Circulators and pumps shall be selected for their intended use based on the heat transfer fluid, intended operating temperature range and pressure. Circulators and pumps shall be installed to allow for service and maintenance. The manufacturer’s installation instructions shall be followed for correct orientation and installation. Motor operated pumps rated 600V or less shall comply with CSA C22.2 No. 108 or UL 778.
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HYDRONICS
temperature and pressure of the system and shall be compatible with the type of heat transfer fluid. Pipe fittings and valves shall be approved for the specific installation with the piping, materials to be installed and shall comply with the applicable standards referenced in Table 1210.1. Where required, exterior piping shall be protected against freezing, UV radiation, corrosion and degradation. Embedded pipe or tubing shall comply with Section 1221.2. 1210.2 Expansion and Contraction. 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, 1R, 2, 4 & 5] Pipe connections less than 2½ inches (64 mm) to heating coils, cool- ing coils, humidifiers, and similar equipment shall have flexible connectors or three (3) 90-degree offsets in close proximity of the connection.
1210.3 Hangers and Supports. Pipe and tubing shall be supported in accordance with Section 313.0. Equipment that is part of the piping system shall be provided with additional support in accordance with this code and manufacturer’s installation instructions. Radiant systems utilizing heat emission or transfer plates shall have a gap of at least ¼ inch (6.4 mm) between adjacent plates. 1210.4 Oxygen Diffusion Corrosion. PEX and PE-RT tubing in closed hydronic systems shall contain an oxygen barrier. 1210.4.1 Vented Closed-Loop Systems. All components installed in a vented closed-loop system shall be constructed of non-ferrous or other corrosion resistant
materials.
1210.4.2 Non-Oxygen Barrier Closed-Loop Sys- tems. All components installed in a non-oxygen barrier system shall be constructed of non-ferrous or other corrosion resistant materials.
1211.0 Joints and Connections.
1211.1 General. 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. Joints between pipe and fittings shall be installed in accordance with the manufacturer’s installation instructions. Joints used underground shall be of an approved type for buried applications in accordance with Section 1221.2.3.
1211.2 Pipe Bends. Pipe bends shall be formed in accordance with Section 1211.2.1 for PEX or Section 1211.2.2 for
PE.
CMC § 3.14 High relevance — show source text
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 or tubing and 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. 1211.10 Polyethylene/Aluminum/Polyethylene (PE- AL-PE). Joints between polyethylene/aluminum/polyethylene (PE-AL-PE) pipe and fittings shall be installed in accordance with one of the following methods: (1) Mechanical joints for PE-AL-PE pipe or tubing and 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 [1] / 8 of an inch (3.2 mm) to [1] / 4 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 or tubing and fittings shall be joined through the compression of a split ring, by a compression nut around the circumference of
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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.
1211.16.2 Plastic Pipe to Other Materials. Where connecting plastic pipe to other types of plastic or other types of piping material; approved listed adapter or transition fittings and listed for the specific transition intended shall be used. Except as provided in the plumbing code, PVC pipe and fittings shall not be solvent welded to any other unlike material.
1212.0 Valves.
CMC § 6.32. High relevance — show source text
** Stainless steel joints shall be welded, assembled with approved tubing fittings, brazed with a material having a melting point in excess of 1000°F (538°C), or assembled with press-connect fittings listed to CSA/ANSI LC 4/CSA 6.32. Brazing alloys and fluxes shall be recommended by the manufacturer for use on stainless steel alloys. [NFPA 54:5.5.7.3] 1308.4.7.4 Flared Joints. Flared joints shall be used only in systems constructed from nonferrous pipe and tubing where experience or tests have demonstrated that the joint is suitable for the conditions and where provisions are made in the design to prevent separation of the joints. [NFPA 54:5.5.7.4] 1308.4.7.5 Metallic Pipe Fittings. Metallic fittings shall comply with the following:
(1) Threaded fittings in sizes exceeding 4 inches (100 mm) shall not be used. (2) Fittings used with steel, stainless steel, or wrought-iron pipe shall be steel, stainless steel, copper alloy, malleable iron, or castiron. (3) Fittings used with copper or copper alloy pipe shall be copper or copper alloy. (4) Fittings used with aluminum alloy pipe shall be aluminum alloy. (5) Cast-iron fittings shall comply with the following: (a) Flanges shall be permitted.
(b) Bushings shall not be used.
(c) Fittings shall not be used in systems containing flammable gas-air mixtures.
(d) Fittings in sizes 4 inches (100 mm) and larger shall not be used indoors unless
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FUEL GAS PIPING
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1308.4.8.3 Compression-Type Mechanical Joints. Where compression-type mechanical joints are used, the gasket material in the fitting shall be compatible with the plastic piping and with the gas distributed by the system. An internal tubular rigid stiffener shall be used in conjunction with the fitting. The stiffener shall be flush with the end of the pipe or tubing and shall extend at least to the outside end of the compression fitting when installed. The stiffener shall be free of rough or sharp edges and shall not be a force fit in the plastic. Split tubular stiffeners shall not be used. [NFPA 54:5.5.8(3)] 1308.4.8.4 Liquefied Petroleum Gas Piping Systems. Plastic piping joints and fittings for use in LP-Gas piping systems shall be in accordance with NFPA 58. [NFPA 54:5.5.8(4)] 1308.4.9 Flange Specifications. Cast iron flanges shall be in accordance with ASME B16.1. [NFPA 54:5.5.9.1.1] 1308.4.9.1 Steel Flanges. Steel flanges shall be in accordance with the following:
(1) ASME B16.5 or
CMC § 1206.2 Medium relevance — show source text
1206.2 Discharge Piping . . . . . . . . . . . . . 259
1207.0 Heating Appliances and Equipment . . . . . . . . . . . . . . . . . . 259
1207.1 General. . . . . . . . . . . . . . . . . . . . . 259
1207.2 Boilers. . . . . . . . . . . . . . . . . . . . . . 259
1207.3 Dual Purpose Water Heaters . . . . 259
1207.4 Solar Heat Collector Systems. . . . 259
1207.5 Heat Pumps . . . . . . . . . . . . . . . . . 259
1208.0 Circulators and Pumps . . . . . . . . . 259
1208.1 General. . . . . . . . . . . . . . . . . . . . . 259
1208.2 Mounting. . . . . . . . . . . . . . . . . . . . 260
1208.3 Sizing . . . . . . . . . . . . . . . . . . . . . . 260
1209.0 Expansion Tanks . . . . . . . . . . . . . 260
1209.1 General. . . . . . . . . . . . . . . . . . . . . 260
1209.2 Installation . . . . . . . . . . . . . . . . . . 260
1209.3 Closed-Type Tanks . . . . . . . . . . . 260
1209.4 Sizing . . . . . . . . . . . . . . . . . . . . . . 260
1210.0 Materials . . . . . . . . . . . . . . . . . . . . 260
1210.1 Piping, Tubing, and Fittings . . . . . 260
1210.2 Expansion and Contraction . . . . . . 260
1210.3 Hangers and Supports . . . . . . . . . 260
1210.4 Oxygen Diffusion Corrosion . . . . . 260
1211.0 Joints and Connections . . . . . . . . 260
1211.1 General. . . . . . . . . . . . . . . . . . . . . 260
1211.2 Pipe Bends . . . . . . . . . . . . . . . . . . 260
Table 1210.1 Materials for Hydronic System Piping, Tubing, and Fittings . . . . . 261
Table 1211.2.2 Minimum Bend Radius
for PE Pipe Installed in Open Cut Trench . . . . . . . . . . . . . 262
1211.3 Chlorinated Polyvinyl Chloride (CPVC) Pipe . . . . . . . . . . . . . . . . . 262
1211.4 CPVC/AL/CPVC Plastic Pipe and Joints . . . . . . . . . . . . . . . . . . . 262
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1211.5 Copper or Copper Alloy Pipe and Tubing . . . . . . . . . . . . . . . . . . 262
CMC § 110.2 Medium relevance — show source text
Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a. The size category is the full-load net refrigeration cooling mode capacity, which is the capacity of the evaporator available for cooling of the thermal load external to the chill-
ing package.
b. For air source heat pumps, compliance with both the 47°F and 17°F heating source outdoor air temperature (OAT) rating efficiency is required for heating.
c. Heating full-load rating conditions are at standard rating conditions defined in AHRI 550/590 (I-P), Table 4, which includes the impact of defrost for air source heating ratings.
d. For units that operate in both cooling and heating, compliance with both the cooling and heating efficiency is required.
e. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
f. For liquid source heat recovery chilling packages that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation
at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
Chilling Packages—Minimum Efficiency Requirements.
g. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3.CMC § 1220.4.8 Medium relevance — show source text
1220.4.8 Testing and Flushing. Testing of snow and ice melt systems shall be in accordance with Section 1205.2 and flushing shall be in accordance with Section 1205.3.
1220.5 Hydronic Makeup Air Units. Hydronic makeup air units that are affected by freezing shall be protected against freezing by a hydronic solution.
1221.0 Piping Installation.
1221.1 General. Piping, fittings, and connections shall be installed in accordance with the conditions of their approval and manufacturer’s installation instructions.
1221.2 Embedded Piping Materials and Joints. Piping embedded in concrete shall be steel pipe, Type L copper tubing or plastic pipe or tubing rated at not less than 80 psi at 180°F (552 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 Section 1221.2.1 through Section 1221.2.3.
1221.2.1 Steel Pipe. Steel pipe shall be welded by electrical arc or oxygen/acetylene method.
1221.2.2 Copper Tubing. Copper tubing shall be joined by brazing with filler metals having a melting point not less than 1000°F (538°C).
1221.2.3 Plastics. Plastic pipe and tubing shall be installed in continuous lengths or shall be joined by heat fusion methods or other approved fittings in accordance with Table 1210.1 and the manufacturer’s installation instructions. Solvent cement joints shall not be used in embedded applications.
1221.3 Pressure Testing. Piping to be embedded in concrete shall be pressure-tested in accordance with Section 1205.2 prior to pouring concrete. During the pour, the pipe system shall maintain the test pressure of not less than one and one-half times the hydronic system operating pressure and 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.
1221.4 System Drainage. Hydronic piping systems shall be installed to permit the system to be drained. The system
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1220.4.2 Tube Length. The maximum loop length of continuous tubing from a supply-and-return manifold arrangement shall not exceed the lengths specified by the manufacturer or, in the absence of manufacturer’s specifications, the lengths specified in Table 1220.4.2. Actual loop lengths shall be determined by spacing, flow rate, and pressure drop in accordance with the system design.
1220.4.3 Multizone Systems. In multizone systems, each zone shall have a tag or label securely affixed to the manifold to indicate the length of the loops and the area(s) served.
TABLE 1220.4.2
MAXIMUM LOOP LENGTHS FOR SNOW
AND ICE MELT SYSTEMS [1,2]
CMC § 1220.3 Medium relevance — show source text
(5) Insulation sheets with integrated knobs for holding the specific type of tube and intended for this application.
(6) Other fasteners recommended by the manufacturer. 1220.3 Spacing of Tube Fasteners. The maximum spacing between tube fasteners within a concrete area shall not exceed the spacing specified by the manufacturer or, in the absence of manufacturer’s specifications, 2.5 feet (762 mm). 1220.4 Snow and Ice Melt Controls. An automatic operating control device that controls the supply hydronic fluid temperature to the snow and ice melt area shall be installed in the system. Snow and ice melt systems shall be protected from freezing with a mixture of propylene glycol or ethylene glycol, and water or other approved fluid. Automotive antifreeze shall not be used.
1220.4.1 Tube Placement. Snow and ice melt tubing shall be installed in accordance with the manufacturer’s installation instructions and with the tube layout and spacing in accordance with the system design. Except for distribution mains, tube spacing and the individual loop lengths shall be installed with a variance of not more than ±10 percent from the design.
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HYDRONICS
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1220.4.7 Insulation. Where a poured concrete snow melt system is installed in contact with the soil, insulation recommended by the manufacturer for such application and with a minimum R-value of 5 shall be placed between the concrete and the compacted grade; and be extended as close as practicable to the outside edges of the concrete.
1220.4.7.1 California Energy Code Insulation Requirements for Heated Slab Floors. See California Energy Code Section 110.8(g) and Table 110.8-A for additional insulation requirements for heated slab floors – a higher level of insulation is required for Climate Zone 16, and more detailed requirements for installing insulation are specified in all climate zones.
1220.4.8 Testing and Flushing. Testing of snow and ice melt systems shall be in accordance with Section 1205.2 and flushing shall be in accordance with Section 1205.3.
1220.5 Hydronic Makeup Air Units. Hydronic makeup air units that are affected by freezing shall be protected against freezing by a hydronic solution.
1221.0 Piping Installation.
1221.1 General. Piping, fittings, and connections shall be installed in accordance with the conditions of their approval and manufacturer’s installation instructions.
1221.2 Embedded Piping Materials and Joints. Piping embedded in concrete shall be steel pipe, Type L copper tubing or plastic pipe or tubing rated at not less than 80 psi at 180°F (552 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 Section 1221.2.1 through Section 1221.2.3.
1221.2.1 Steel Pipe. Steel pipe shall be welded by electrical arc or oxygen/acetylene method.
1221.2.2 Copper Tubing. Copper tubing shall be joined by brazing with filler metals having a melting point not less than 1000°F (538°C).
CMC § 90.1 Medium relevance — show source text
(3) Variable flow is not required for primary pumps in a primary/secondary system.
(4) Variable flow is not required for a coil pump provided for freeze protection.
(5) Variable flow is not required for heat recovery coil runaround loops. [ASHRAE 90.1:6.5.4.2]
CHILLED WATER PUMPS
IN THESE
CLIMATE ZONESHEATING WATER
PUMPS IN THESE
CLIMATE ZONESMOTOR
NAMEPLATE
HORSEPOWER
0A, 0B, 1A, 1B, 2BNR ≥2 hp
2A, 3BNR ≥3 hp
3A, 3C, 4A, 4B7, 8 ≥5 hp
4C, 5A, 5B, 5C, 6A, 6B3C, 5A, 5C, 6A, 6B ≥7.5 hp
─4A, 4C, 5B ≥10 hp 7, 8 4B ≥15 hp
─2A, 2B, 3A, 3B ≥25 hp
─1B ≥100 hp
─0A, 0B, 1A ≥200 hp For SI units: 1 horsepower = 0.746 kW
E 503.5.7.3 Chiller and Boiler Isolation. Where a chilled-water plant includes more than one chiller, provisions shall be made so that the fluid flow through the chiller is automatically shut off where the chiller is shut down. Chillers piped in series for the purpose of increased temperature differential, shall be considered as one chiller. Where constant-speed chilled-water or condenser water pumps are used to serve multiple chillers, the number of pumps shall be not less than the number of chillers and staged on and off with the chillers. [ASHRAE 90.1:6.5.4.3.1]
E 503.5.7.3.1 Boiler Isolation. Where a boiler plant includes more than one boiler, provisions shall be made so that the flow through the boiler is automatically shut off where the boiler is shut down. Where constant-speed hot-water pumps are used to serve multiple boilers, the number of pumps shall be not less than the number of boilers and staged on and off with the boilers.
[ASHRAE 90.1:6.5.4.3.2]
E 503.5.7.4 Chilled- and Hot-Water Tempera- ture Reset Controls. Chilled- and hot-water systems with a design capacity exceeding 300 000 Btu/h (88 kW) supplying chilled or heated water to comfort conditioning systems shall include controls that automatically reset supply water temperatures by representative building loads (including return water temperature) or by outdoor air temperature. Where DDC is used to control valves, the set point shall be reset based on valve positions until one valve is nearly wide open or setpoint limits of the system equipment or application have been reached.
Exceptions:
CMC § 000002-001 Medium relevance — show source text
(in)|EFV
Flow
Series|Maximum
Total
Connected
Load
(scfh)|Maximum
Service
Length
(ft)|Maximum
Total
Connected
Load
(scfh)|Maximum
Service
Length
(ft)|Maximum
Service
Length
(ft)|Maximum
Service
Length
(ft)|Maximum
Service
Length
(ft)**| |½ CTS|400|357|177|400|341|M025078|Lyall|EFV100-
000002-001| |½ CTS|400|385|122|395|251|M020947|Honeywell
Perfection|51716| |½ CTS|775|692|30|775|72|M025079|Lyall|EFV100-
000011-001| |½ CTS|800|700|28|790|66|M020949|Honeywell
Perfection|51713| |1 CTS|775|692|1419|775|2916|M025080|Lyall|EFVEC-
BB3DT00-004| |1 CTS|800|700|1000|790|2355|M020951|Honeywell
Perfection|51715XMD| |1 CTS|1200|1072|523|1200|1196|M025081|Lyall|EFVED-
BB3DT00-004| |1 CTS|1800|1584|104|1800|385|M025082|Lyall|EFVEE-
BB3DT12-004| |1 CTS|1800|1620|122|1775|437|M020954|Honeywell
Perfection|51745XMD| |1¼ IPS|2600|2322|952|2600|1897|M025084|Lyall|EFV300-
000002-003| |2 IPS|55003|4818|1495|5000|2855|M025086|Lyall|EFV300-
000008-002|- The values in this column are based on a 10 psig design pressure.
- The values in this column are based on a 20 psig design pressure.
- 2-inch IPS 5500 EFVs can be used with two reducers and installed on 1¼ IPS service lines. Appendix B provides examples to perform equivalent length calculations, where the maximum service length for NOP ≥ 10 psig is 239 ft and the maximum service length for NOP ≥ 24 psig is 456 ft.
4.3. Specifications and material codes for electrofusion couplings with an incorporated EFV are listed in Table 5.
Printed copies of this document might be out of date. The Technical Information Library (TIL) has the current version.
PG&E Internal Information “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2021 Pacific Gas and Electric Company. All rights reserved.
Page 5 of 19
Excess Flow Valves A-93.3
CMC § 20.1. Medium relevance — show source text
(2) Solvent cement joints for PVC pipe and 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 per
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(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. Turn 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 or tubing and 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. 1211.10 Polyethylene/Aluminum/Polyethylene (PE- AL-PE). Joints between polyethylene/aluminum/polyethylene (PE-AL-PE) pipe and fittings shall be installed in accordance with one of the following methods: (1) Mechanical joints for PE-AL-PE pipe or tubing and fittings shall be either of the metal insert fittings with a split ring and compression nut or metal insert fittings with copper crimp rings.
CMC § 503.5.7.7 Medium relevance — show source text
E 503.5.7.7 Chilled-Water Coil Selection.
Chilled-water cooling coils shall be selected to provide a 15°F (8°C) or higher temperature difference between leaving and entering water temperatures and a minimum of 57°F (14°C) leaving water temperature at design conditions.
Exceptions:
(1) Chilled-water cooling coils that have an air-side pressure drop exceeding 0.70 inch of water (0.17 kPa) when rated at 500 feet per minute (2.54 m/s) face velocity and dry conditions (no condensation).
(2) Individual fan-cooling units with a design supply airflow rate 5000 cubic feet per minute (ft [3] /min) (2.36 m [3] /s) and less.
(3) Constant-air-volume systems.
(4) Coils selected at the maximum temperature difference allowed by the chiller.
(5) Passive coils (no mechanically supplied airflow).
(6) Coils with design entering chilled-water temperatures of 50°F (10°C) and higher.
(7) Coils with design entering air dry-bulb temperatures of 65°F (18°C) and lower. [ASHRAE 90.1:6.5.4.7]
E 503.5.8 Heat Rejection Equipment. Section E 503.5.8 through Section E 503.5.9 applies to heat-rejection equipment used in comfort cooling systems, such as air-cooled condensers, dry coolers, open-circuit cooling towers, closed-circuit cooling towers, and evaporative condensers.
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(3) Water temperature reset is not required where valve position is used to comply with Section E 503.5.7. [ASHRAE 90.1:6.5.4.4]
E 503.5.7.5 Hydronic (Water Loop) Heat Pump and Water-Cooled Unitary Air Condi- tioners. Hydronic heat pumps and water-cooled unitary air-conditioners shall have a two-position automatic valve interlocked to shut off water flow
when the compressor is off.
Exception: Units employing fluid economizers.
[ASHRAE 90.1:6.5.4.5.1]
E 503.5.7.5.1 Controls. Hydronic heat pumps and water-cooled unitary air-conditioners having a total pump system power exceeding 5 hp (3.7 kW) shall have controls, devices, or both (such as variable speed control) that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. [ASHRAE 90.1:6.5.4.5.2]
E 503.5.7.6 Pipe Sizing. Chilled-water and condenser-water piping shall be designed such that the design flow rate in each piping segment shall not exceed the values listed in Table E 503.5.7.6 for the
appropriate total annual hours of operation. Piping size selections for systems that operate under variable flow conditions (e.g., modulating two-way control valves at coils) and that contain variable-speed pump motors shall be permitted to be made from the “Variable Flow/Variable Speed” columns. All others shall be made from the “Other” columns.
Exceptions:
CMC § 1310.14.5 Medium relevance — show source text
Gas mixing machines. . . . . . . . . . . . . . . . . . . 1310.14.5
Inspection of safety . . . . . . . . . . . . . . . . . . . . . . 516.6.4
Mechanical air supply . . . . . . . . . . . . . . . . . . . . . 701.9.2
Motorized louvers . . . . . . . . . . . . . . . . . . . . . . . 701.10.2
Recirculating systems . . . . . . . . . . . . . . . . . . . . . . 516.3 Stack dampers . . . . . . . . . . . . . . . . . . . . . . . . . . 1003.4
– J –
JOINTS AND CONNECTIONS . . . . . . . . . . . . . . . . . 1109.2,
1109.8, 1211.0,
1308.4.8–1308.4.9.6
Brazed joint . . . . . . . . . . . . . . . . . . . . . . . 212.0, 1211.4 Copper or copper alloy pipe or tubing . . . . . . . 1109.2, 1211.4, 1211.16.1
CPVC piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1211.3
Embedded piping and joints . . . . . . . . . . . . . . . . 1221.2
Expansion joint. . . . . . . . . . . . . . . . . . . . . . . . . 1313.2.2
Flared. . . . . . . . . . . . . . . . . . . . . . . . . . . . 212.0, 1211.4,
1308.4.7.4, 1308.4.7.5
Mechanical joint . . . . . . . . . . . . . . 212.0, 1109.7, 1211.6,
1211.7, 1211.9, 1211.10,
1211.13, 1211.14,
1308.4.8.3
PE pipe or tubing . . . . . . . . . . . . . . . . . . . . . . . . . 1211.9
PE-AL-PE pipe or tubing . . . . . . . . . . . . . . . . . . 1211.10
PE-RT piping or tubing. . . . . . . . . . . . . . . . . . . . 1211.11
PEX pipe or tubing. . . . . . . . . . . . . . . . . . . . . . . . 1211.6
PEX-AL-PEX pipe or tubing . . . . . . . . . . . . . . . . . 1211.7
Plastic piping, joints, and fittings . . . . . . . . . . . 1211.16.2
PP piping or tubing. . . . . . . . . . . . . . . . . . . . . . . 1211.12
CMC § 1102.3 Medium relevance — show source text
Chapter 10 Boilers and Pressure Vessels. Chapter 10 regulates the construction, installation, operation, repair, and alteration of boilers and pressure vessels. The safety provisions within this chapter address controls and limit devices for automatic boilers, methods of determining expansion tank capacities, discharge piping, relief valves, shutoff valves, gas-pressure and combustion regulators, and inspections and tests. Potable water heaters are free from the requirements of Chapter 10 as they are within the scope of the Uniform Plumbing Code (UPC).
Pressure vessels store large amounts of energy and must comply with ASME Boiler and Pressure Vessel Code (BPVC) Section VIII.1. The stored energy must be contained to prevent disastrous failures. Boilers must comply with ASME BPVC Section I, ASME BPVC Section IV, or NFPA 85. Installing a safety relief valve and expansion tank prevents pressures in the tank from exceeding the design threshold.
Chapter 11 Refrigeration. Chapter 11 regulates the design, installation, and construction requirements of refrigeration systems and the installation and construction of cooling towers. Refrigeration is a method used for achieving heat transfer to cool spaces. Refrigerants are the most common medium used to transfer the heat energy from the low-temperature level to the high-temperature level. Table
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FORMAT OF THE UNIFORM MECHANICAL CODE
1102.3 lists the most commonly used refrigerants and is labeled by a number. The concentration limits provided in Table 1102.3 are useful for the quantity of refrigerant required to cool a volume of space safely.
A major milestone reached in the industry was the introduction of lower flammability refrigerants such as A2L and B2L. The industry’s concerns to address lower Global Warming Potential (GWP) refrigerants led to the development of these lower flammability refrigerants. Chapter 11 does not only include these lower flammability refrigerants in Table 1102.3, but it also contains specific A2L and B2L provisions to address the precautions necessary for the proper use of these products. In particular, high-probability systems using A2L refrigerants for human comfort applications are covered by provisions which include refrigerant concentration limits, mechanical ventilation, ignition sources, compressors and pressure vessels, and refrigerant sensors.
In addition, Chapter 11 addresses other minimum requirements for refrigeration systems such as refrigeration machinery rooms (including ventilation), relief valves, and pressure vessels. Apart from refrigerants, the chapter also addresses minimum requirements for systems that use other mediums such as ammonia and brine systems. For ammonia systems, such systems are required to comply with IIAR 2, IIAR 3, IIAR/ANSI 4, IIAR 5, and IIAR 6.
Chapter 12 Hydronics. Chapter 12 regulates hydronic systems that are part of heating, cooling, ventilation, and conditioning systems. Such piping systems include steam, hot water, radiant heating and cooling, chilled water, steam condensate, condenser water, ground source heat pump systems, snow and ice melt systems, ambient temperature loops, and district ambient temperature loops. Provisions within this chapter addressing ground source heat pumps and ambient temperature loops apply to the hydronic portions of the system. Geothermal energy systems, including ground source heat pumps and ambient temperature loops, are regulated by Chapter 17.
CMC § 105.6 Medium relevance — show source text
INDEX
Unlimited Area Buildings 507 Unsafe Structures and Equipment (see Structures, Unsafe) 116 Appeals 113, Appendix B Revocation of permit 105.6 Stop work orders 115 Utilities disconnection 112.3
Unstable Materials 307.3, Table 414.2.5.1, Table 414.5.1, Table 415.6.5, 415.7.1, 415.9 Unusable Space 711.2.6 Use and Occupancy Chapter 3 Accessory 508.2 Classification 302.1
Detailed requirements based on occupancy and use Chapter 4 Incidental uses 509, Table 509.1 Mixed 508.3, 508.4 Use designation 302.2 Utilities 112
Service connection 112.1
Service disconnection 112.3
Temporary connection 112.2 Utility and Miscellaneous Occupancy (Group U) 312 Accessibility Chapters 11A and 11B Agricultural buildings Appendix C Area 503, 505, 506, 507, 508 Flood provisions Appendix G Height 503, 504, 508 Incidental uses 509
Live loads Table 1607.1 Means of egress Exit signs 1013.1 Stairway, exit access 1019 Mixed occupancies 508.3, 508.4 Special provisions Private garages and carports 406.3 Residential aircraft hangars 412.4 Sprinkler protection 903.2.11 Travel distance 1006.2.1, 1006.3,
1017.1 UV Germicidal Irradiation Systems
1211
Valuation or Value (see Fees, Permit) 109.3 Vapor Diffusion Port 202 Vapor Retarders 1202.3, 1404.3, 1404.3.2 Vegetative Artificial decorative 419, 419.1 Vegetative roofs 1505.10, 1507.15 Vehicle Barrier 1607.11 Vehicle Barrier Systems 406.4.2, 1607.11 Vehicle Show Rooms 304 Vehicular Fueling 406.7 Vehicular Gates 3110 Vehicular Repair 406.8
Veneer Cement plaster 1404.16, 1411 Fastening 1404.5 Fiber-cement siding 1404.17, 1411 Glazing 1404.13, 1411 Masonry, adhered 1404.11, 2101.2.1, 2103.2.4 Masonry, anchored 1404.7, 1411, 2101.2.1
Metal 1404.12
Plastic 1411, 2605 Slab-type 1404.9, 1411
Testing Automatic fire-extinguishing systems 904.4
Automatic water mist systems 904.11.3 Building official required 104.2.3.6 Carbon dioxide systems 904.8 Clean agent system 904.10 Dry chemical systems 904.6 Emergency and standby power 2702.4 Fire alarm systems 907.7, 907.8 Fire pumps 913.5 Fire-resistant materials 703.2
CMC § 1211.4 Medium relevance — show source text
ASTM F2165, CSA B137.9| |Chlorinated Polyvinyl Chloride/Alu-
minum/ Chlorinated Polyvinyl Chloride
(CPVC/AL/CPVC)|ASTM F2855|ASTM D2846|Notes: 1 Ductile and gray iron. 2 Only type K, L, or M tubing allowed to be installed.
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HYDRONICS
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. 1211.4 CPVC/AL/CPVC Plastic Pipe and Joints. Joints between chlorinated polyvinyl chloride/aluminum/ chlorinated polyvinyl chloride (CPVC/AL/CPVC) pipe and fittings shall be installed in accordance with one of the following methods:
(1) Mechanical joints shall include flanged, grooved, and push-fit fittings.
(2) Solvent cement joints for CPVC/AL/CPVC pipe and fittings shall be clean from dirt and moisture. Solvent cements in accordance with ASTM F493, requiring the use of a primer shall be orange in color. The primer shall be colored and be in accordance with ASTM F656.
Listed solvent cement in accordance with ASTM F493 that does not require the use of primers, yellow in color, shall be permitted for pipe and fittings manufactured in accordance with ASTM D2846, [1] ⁄ 2 of an inch (15 mm) through 2 inches (50 mm) in diameter, [1] ⁄ 2 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. 1211.5 Copper or Copper Alloy Pipe and Tubing. Joints between copper or copper alloy pipe or tubing and fittings shall be installed in accordance with one of the following methods:
(1) Brazed joints between copper or copper alloy pipe or tubing and 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.
CMC § 604.1 Medium relevance — show source text
CHLORINATED POLYVINYL
CHLORIDE/ALUMINUM/CHLORINATED
POLYVINYL CHLORIDE
(CPVC-AL-CPVC) PIPE OR TUBING
Approved standards, water supply . . . . . . . .Table 604.1
Joining and connections . . . . . . . . . . . . . . . .(see Joints
and connections)
CIRCUIT VENTING . . . . . . . . . . . . . . . . . . . . . . . . . . . .911.0
CLARIFIERS . . . . . . . . . . . . . . . . . . . . . . . . . .205.0, 1009.0
CLEANOUT PLUGS OR CAPS . . . . . . . . . . .707.1 – 707.3,
707.13, 1107.2
CLEANOUTS
Access . . . . . . . . . . . . . . . . . . . . . .707.8, 719.5, 801.3.2
Building sewer . . . . . . . . . . . . . . . . . . . . . . 310.12, 719.0 Change of direction . . . . . . . . . . . . . . . . . .707.4, 719.1,
801.3.2, 803.3, 1002.3
Clearances . . . . . . . . . . . . . . . . . . . . . . . . .707.8, 707.9
Condensate drain . . . . . . . . . . . . . . . . . . . . . . . .814.3.1
Cover plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .707.8
Direction of flow . . . . . . . . . . . . . . . . . . . . . .707.5, 719.4
Horizontal drains . . . . . . . . . . . . . . . . . . . . .707.4, 719.1
Manholes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .719.6
Plugs . . . . . . . . . . . . . . . . . . . . . . . .707.1, 707.2, 707.12
Prohibited use of . . . . . . . . . . . . . . . . . . . . . . . . . .316.1
Size . . . . . . . . . . . . . . . . . . . . . . . . . .707.1, Table 707.1
Soil or drainpipes . . . . . . . . . . . . . . . . . . . . . . . . . .317.1
Where required . . . . . . . . . . . . . . . .707.4, 719.1, 909.1,
910.6, 1002.3, 1008.1,
1017.1, 1101.13.1, E 301.4
CLEARANCE
CMC § 1211.3 Medium relevance — show source text
1211.3 Chlorinated Polyvinyl Chloride (CPVC) Pipe. Joints between chlorinated polyvinyl chloride (CPVC) pipe and fittings shall be installed in accordance with one of the following methods:
(1) Mechanical joints shall include flanged, grooved, and push fit fittings. 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 from dirt and moisture. Solvent cements in accor dance 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, green, or red in color, shall be permitted for pipe and fittings manufactured in accordance with ASTM D2846, [1] / 2 of an inch (15 mm) through 2 inches (50 mm) in diameter or ASTM F442, [1] / 2 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
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HYDRONICS
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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 [1] / 4 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.
CMC § 12-6 Medium relevance — show source text
1203 Temperature Control . . . . . . . . . . . . . . . . . . . . . . . . . . 12-6
1204 Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-7
1205 Yards or Courts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-7
1206 Sound Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-8
1207 Enhanced Classroom Acoustics . . . . . . . . . . . . . . . . . 12-8
1208 Interior Space Dimensions . . . . . . . . . . . . . . . . . . . . . 12-8
1209 Access to Unoccupied Spaces. . . . . . . . . . . . . . . . . . . 12-9
1210 Toilet and Bathroom Requirements . . . . . . . . . . . . . 12-9
1211 UV Germicidal Irradiation Systems . . . . . . . . . . . . . 12-10
1212 [HCD 1 & HCD 2] Garage Door Springs . . . . . . . . . . . .12-10
1213 [HCD 1] Pollutant Control . . . . . . . . . . . . . . . . . . . . . . .12-11
1214 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1215 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1216 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1217 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1218 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1219 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1220 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
1221 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-11
Frequently asked questions
Do all joints have to be “listed” or “approved”?
Yes—joints must be an approved type and installed per the manufacturer; many plastic joint types require listed fittings or specific ASTM standard compliance as referenced in § 1211.1 and the material subsections.
Can I solvent‑cement CPVC joints that will be embedded in concrete?
No — for piping to be embedded in concrete the code requires heat‑fusion or other approved joints and explicitly restricts solvent‑cement joints in embedded applications (see § 1221.2.3).
Is threading CPVC allowed for valves and fittings?
Yes, but only with Schedule 80 minimum and the code requires a 50% reduction in pressure rating for threaded CPVC joints; use compatible thread sealant and follow the manufacturer’s instructions (§ 1211.3).
What brazing temperature is required for copper joints?
Brazing filler metals used on copper must have a liquid temperature above 1000°F (538°C) and meet AWS A5.8; joints must be cleaned and prepared as required by § 1211.5.
Are press‑fit copper joints allowed?
Yes — press‑connect fittings with an elastomeric O‑ring are allowed for copper; installation requires full insertion, cutting square, chamfering/reaming, and use of the tool recommended by the fitting manufacturer (§ 1211.5).
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