CMC · California Mechanical Code
Condensate, drainage, and plumbing connections
This hub summarizes CMC and CPC rules for collecting, protecting, sizing, and discharging condensate and related clear water wastes (see CMC § 310.x and CPC Ch. 8).
Last reviewed: July 6, 2026
Overview
This part of the California Mechanical Code (CMC) governs collection, control, material, sizing, and the point‑of‑discharge for condensate and other clear water wastes from HVAC and related equipment. Key CMC provisions include condensate disposal and overflow protection (for example, § 310.1 and § 310.2), minimum condensate pipe sizing and material requirements (§ 310.3), and the required indirect connection/air‑gap at the point of discharge (§ 310.5) — see the CMC text for these specific rules.
Where the drainage system is governed by the California Plumbing Code (CPC), Chapter 8 (Indirect Wastes) and its condensate provisions set parallel requirements for disposal, pump use, cleanouts, materials, and protections for undiluted or high‑temperature condensate (for example, CPC §§ 801.2, 814.1–814.6 and related tables). Those CPC provisions describe acceptable receptors, air gaps/air breaks, minimum pipe sizes and when indirect wastes or special materials are required.
Practically, designers and installers should confirm: (1) that condensate drains slope and size per the code or manufacturer instructions; (2) overflow protection (secondary pan, level shutoff) is provided where damage could occur; and (3) discharge is to an approved receptor or indirect waste connection with required air gap/air break and acceptable materials — see CMC § 310.x and CPC Chapter 8 for the implementing details.
In this section
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 310.2.1 High relevance — show source text
310.2.1 Protection of Appurtenances. Where insulation or appurtenances are installed where damage is capable of resulting from a condensate drain pan overfill, such installations shall occur above the rim of the drain
pan with supports. Where the supports are in contact with the condensate waste, the supports shall be of approved corrosion-resistant material.
310.3 Condensate Waste Pipe Material and Sizing. Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 310.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment, and shall be approved for use with the liquid being discharged.
TABLE 310.3
MINIMUM CONDENSATE PIPE SIZE
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GENERAL REGULATIONS
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in the plumbing code. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.
310.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut.
310.4 Appliance Condensate Drains. Condensate drain lines from individual condensing appliances shall be sized as required by the manufacturer’s instructions. Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer.
310.5 Point of Discharge. Air-conditioning condensate waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 310.4.
310.6 Condensate Waste from Air-Conditioning Coils. Where the condensate waste from air-conditioning coils discharges by direct connection to a lavatory tailpiece or to an approved accessible inlet on a bathtub overflow, the connection shall be located in the area controlled by the same person controlling the air-conditioned space. 310.7 Female Plastic Connections. Female plastic screwed fittings shall be used with plastic male fittings and plastic male threads. Female plastic threaded connections shall not be allowed to be used when threaded onto a male
metallic connection.
311.0 Heating or Cooling Air System. 311.1 Source. A heating or cooling air system shall be provided with return air, outside air, or both. A heating or cooling air system regulated by this code and designed to replace required ventilation shall be arranged to discharge into a conditioned space not less than the amount of outside air specified in Chapter 4.
CMC § 310.1 High relevance — show source text
310.1 Condensate Disposal . . . . . . . . . . . 57
310.2 Condensate Control . . . . . . . . . . . . 57
310.3 Condensate Waste Pipe Material and Sizing. . . . . . . . . . . . . . . . . . . . 57
Table 310.3 Minimum Condensate Pipe Size. . . 57
310.4 Appliance Condensate Drains . . . . 58
310.5 Point of Discharge . . . . . . . . . . . . . 58
310.6 Condensate Waste from
Air-Conditioning Coils . . . . . . . . . . . 58
310.7 Female Plastic Connections . . . . . . 58
311.0 Heating or Cooling Air System . . . . 58
311.1 Source . . . . . . . . . . . . . . . . . . . . . . 58
311.2 Air Filters . . . . . . . . . . . . . . . . . . . . 58
311.3 Prohibited Sources . . . . . . . . . . . . . 58
311.4 Return-Air Limitations . . . . . . . . . . . 58
311.5 California Energy Code Requirements for Residential
Air Filtration . . . . . . . . . . . . . . . . . . 59
312.0 Plumbing Connections . . . . . . . . . . 59
312.1 General. . . . . . . . . . . . . . . . . . . . . . 59
313.0 Hangers, Supports, and Anchors . . 59
313.1 General. . . . . . . . . . . . . . . . . . . . . . 59
313.2 Material. . . . . . . . . . . . . . . . . . . . . . 59
313.3 Suspended Piping . . . . . . . . . . . . . 59
313.4 Alignment . . . . . . . . . . . . . . . . . . . . 59
313.5 Underground Installation . . . . . . . . 59
313.6 Hanger Rod Sizes . . . . . . . . . . . . . 59
Table 313.6 Hanger Rod Sizes . . . . . . . . . . . . . 59
313.7 Gas Piping . . . . . . . . . . . . . . . . . . . 59
314.0 Balancing . . . . . . . . . . . . . . . . . . . . 59
314.1 General. . . . . . . . . . . . . . . . . . . . . . 59
315.0 Louvers in Hurricane Prone
Regions . . . . . . . . . . . . . . . . . . . . . 59
315.1 General. . . . . . . . . . . . . . . . . . . . . . 59
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316.0 Protection of Piping, Tubing, Materials, and Structures . . . . . . . . 59
316.1 General. . . . . . . . . . . . . . . . . . . . . . 59
CMC § 305.6 High relevance — show source text
305.6 Outdoor Locations . . . . . . . . . . . . . 55
306.0 Automatic Control Devices . . . . . . . 55
306.1 General. . . . . . . . . . . . . . . . . . . . . . 55
306.2 Building Automation Systems . . . . 56
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TABLE OF CONTENTS
307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56
307.1 Fuel-Burning Appliances . . . . . . . . 56
307.2 Electric Heating Appliances . . . . . . 56
307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56
307.4 Absorption Units . . . . . . . . . . . . . . . 56
308.0 Improper Location. . . . . . . . . . . . . . 57
308.1 General. . . . . . . . . . . . . . . . . . . . . . 57
309.0 Workmanship . . . . . . . . . . . . . . . . . 57
309.1 Engineering Practices. . . . . . . . . . . 57
309.2 Concealing Imperfections . . . . . . . . 57
309.3 Installation Practices. . . . . . . . . . . . 57
310.0 Condensate Wastes and Control . . 57
310.1 Condensate Disposal . . . . . . . . . . . 57
310.2 Condensate Control . . . . . . . . . . . . 57
310.3 Condensate Waste Pipe Material and Sizing. . . . . . . . . . . . . . . . . . . . 57
Table 310.3 Minimum Condensate Pipe Size. . . 57
310.4 Appliance Condensate Drains . . . . 58
310.5 Point of Discharge . . . . . . . . . . . . . 58
310.6 Condensate Waste from
Air-Conditioning Coils . . . . . . . . . . . 58
310.7 Female Plastic Connections . . . . . . 58
311.0 Heating or Cooling Air System . . . . 58
311.1 Source . . . . . . . . . . . . . . . . . . . . . . 58
311.2 Air Filters . . . . . . . . . . . . . . . . . . . . 58
311.3 Prohibited Sources . . . . . . . . . . . . . 58
311.4 Return-Air Limitations . . . . . . . . . . . 58
311.5 California Energy Code Requirements for Residential
Air Filtration . . . . . . . . . . . . . . . . . . 59
312.0 Plumbing Connections . . . . . . . . . . 59
312.1 General. . . . . . . . . . . . . . . . . . . . . . 59
CMC § 814.2 Medium relevance — show source text
814.2 Condensate Control. Where any equipment or appliance is installed in a space where damage is capable of resulting from condensate overflow, a drain line shall be provided and shall be drained in accordance with Section 814.1.
An additional protection method for condensate overflow shall be provided in accordance with one of the following:
(1) A water level detecting device that will shut off the equipment or appliance in the event the primary drain is blocked. Such detecting device shall be in accordance with the manufacturer’s installation instructions.
(2) An additional watertight pan of corrosion-resistant material, with a separate drain line, installed beneath the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain.
(3) An additional separate drain line at a level that is higher than the primary drain line connection of the drain pan.
(4) An additional watertight pan of corrosion-resistant material with a water level detection device installed beneath
the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain and to shut off the equipment.
The additional pan or the additional drain line connection shall be provided with a drainpipe of not less than [3] ⁄ 4 of an inch (20 mm) nominal pipe size, discharging at a point that is readily observed.
814.2.1 Protection of Appurtenances. Where insulation or appurtenances are installed where damage is capable of resulting from a condensate drain pan overfill, such installations shall occur above the rim of the drain
pan with supports. Where the supports are in contact with the condensate waste, the supports shall be of approved corrosion-resistant material.
814.3 Condensate Waste Pipe Material and Sizing. Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 814.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment and shall be approved for use with the liquid being discharged.
TABLE 814.3
MINIMUM CONDENSATE PIPE SIZE
EQUIPMENT CAPACITY IN TONS
OF REFRIGERATIONMINIMUM CONDENSATE PIPE
DIAMETER
(inches)Up to 20 3⁄4
21 – 401
41 – 9011⁄4
91 – 12511⁄2
126 – 2502 For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm
The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running threequarters full at the following pipe conditions:
Outside Air – 20% Col2 Room Air – 80% Col4
DBWB DB WB
90°F73°F 75°F 62.5°FFor SI units: °C = (°F-32)/1.8
CMC § 805.0 Medium relevance — show source text
No standpipe receptor for a clothes washer shall extend more than 30 inches (762 mm), or not less than 18 inches (457 mm) above its trap weir. No trap for a clothes washer standpipe receptor shall be installed below the floor, but shall be roughed in not less than 6 inches (152 mm) and not more than 18 inches (457 mm) above the floor. No indirect waste receptor shall be installed in a toilet room, closet, cupboard, or storeroom, or in a portion of a building not in general use by the occupants thereof; except standpipes for clothes washers shall be permitted to be installed in toilet and bathroom areas where the clothes washer is installed in the
same room.
805.0 Pressure Drainage Connections. 805.1 General. Indirect waste connections shall be provided for drains, overflows, or relief vents from the water supply system, and no piping or equipment carrying wastes or producing wastes or other discharges under pressure shall be directly connected to a part of the drainage system.
The preceding shall not apply to an approved sump pump or to an approved pressure-wasting plumbing fixture or device where the Authority Having Jurisdiction has been satisfied that the drainage system is adequately sized to accommodate the anticipated discharge thereof.
806.0 Sterile Equipment.
806.1 General. Appliances, devices, or apparatus such as stills, sterilizers, and similar equipment requiring water and waste and used for sterile materials shall be drained through an air gap.
807.0 Appliances.
807.1 Non-Classed Apparatus. Commercial dishwashing machines, silverware washing machines, and other appliances, devices, equipment, or other apparatus not regularly classed as plumbing fixtures, which are equipped with pumps, drips, or drainage outlets, shall be permitted to be drained by indirect waste pipes discharging through an air break into an approved type of open receptor.
807.2 Undiluted Condensate Waste. Where undiluted condensate waste from a fuel-burning condensing appliance is discharged into the drainage system, the material in the drainage system shall be cast-iron, galvanized iron, plastic, or other materials approved for this use.
Exceptions:
(1) Where the above condensate is discharged to an exposed fixture tailpiece and trap, such tailpiece and trap shall be permitted to be a copper alloy.
(2) Materials approved in Section 701.0 shall be permitted to be used where data is provided that the condensate waste is adequately diluted.
807.3 Domestic Dishwashing Machine. No domestic dishwashing machine shall be directly connected to a drainage system or food waste disposer without the use of an approved dishwasher air gap fitting on the discharge side of the dishwashing machine. Listed dishwasher air gap fittings shall be installed with the flood-level (FL) marking at or above the flood level of the sink or drainboard, whichever is higher.
808.0 Cooling Water.
808.1 General. Where permitted by the Authority Having Jurisdiction, clean running water used exclusively as a cooling medium in an appliance, device, or apparatus shall be permitted to discharge into the drainage system through the inlet side of a fixture trap in the event that a suitable fixture is not available to receive such discharge. Such trap connection shall be by means of a pipe connected to the inlet side of an approved fixture trap, the upper end terminating in a funnelshaped receptacle set adjacent, and not less than 6 inches (152 mm) above the overflow rim of the fixture.
CMC § 10.4 Medium relevance — show source text
The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running threequarters full at the following pipe conditions:
Outside Air – 20% Col2 Room Air – 80% Col4 DB WB DB WB 90°F 73°F 75°F 62.5°F For SI units: °C = (°F-32)/1.8
blocked. Such detecting device shall be in accordance with the manufacturer’s installation instructions.
(2) An additional watertight pan of corrosion-resistant material, with a separate drain line, installed beneath the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain.
(3) An additional separate drain line at a level that is higher than the primary drain line connection of the drain pan.
(4) An additional watertight pan of corrosion-resistant material with a water level detection device installed beneath
the cooling coil, unit, or the appliance to catch the overflow condensate due to a clogged primary condensate drain and to shut off the equipment.
The additional pan or the additional drain line connection shall be provided with a drain pipe of not less than [3] ⁄ 4 of an inch (20 mm) nominal pipe size, discharging at a point that is readily observed.
310.2.1 Protection of Appurtenances. Where insulation or appurtenances are installed where damage is capable of resulting from a condensate drain pan overfill, such installations shall occur above the rim of the drain
pan with supports. Where the supports are in contact with the condensate waste, the supports shall be of approved corrosion-resistant material.
310.3 Condensate Waste Pipe Material and Sizing. Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 310.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment, and shall be approved for use with the liquid being discharged.
TABLE 310.3
MINIMUM CONDENSATE PIPE SIZE
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GENERAL REGULATIONS
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in the plumbing code. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.
310.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut.
CMC § 801.7 Medium relevance — show source text
801.7 Drip or Drainage Outlets . . . . . . . .181
802.0 Approvals . . . . . . . . . . . . . . . . . . .181
802.1 General . . . . . . . . . . . . . . . . . . . . .181
803.0 Indirect Waste Piping . . . . . . . . . .181
803.1 Materials . . . . . . . . . . . . . . . . . . . .181
803.2 Copper and Copper Alloys . . . . . .181
803.3 Pipe Size and Length . . . . . . . . . .181
804.0 Indirect Waste Receptors . . . . . . .182
804.1 Standpipe Receptors . . . . . . . . . .182
805.0 Pressure Drainage Connections . . . . . . . . . . . . . . . . .182
805.1 General . . . . . . . . . . . . . . . . . . . . .182
806.0 Sterile Equipment . . . . . . . . . . . . .182
806.1 General . . . . . . . . . . . . . . . . . . . . .182
807.0 Appliances . . . . . . . . . . . . . . . . . .182
807.1 Non-Classed Apparatus . . . . . . . .182
807.2 Undiluted Condensate Waste . . . .182
807.3 Domestic Dishwashing Machine . . . . . . . . . . . . . . . . . . . .182
808.0 Cooling Water . . . . . . . . . . . . . . . .182
808.1 General . . . . . . . . . . . . . . . . . . . . .182
809.0 Drinking Fountains . . . . . . . . . . . .182
809.1 General . . . . . . . . . . . . . . . . . . . . .182
810.0 Steam and Hot Water Drainage Condensers and Sumps . . . . . . . .182
810.1 High-Temperature Discharge . . . .182
Table 810.1 Pipe Connections in Blowoff Condensers and Sumps . . . . . . . .183
810.2 Sumps, Condensers, and Intercepting Tanks . . . . . . . . . . . .183
810.3 Cleaning . . . . . . . . . . . . . . . . . . . .183
810.4 Strainers . . . . . . . . . . . . . . . . . . . .183
811.0 Chemical Wastes . . . . . . . . . . . . .183
811.1 Pretreatment . . . . . . . . . . . . . . . . .183
811.2 Waste and Vent Pipes . . . . . . . . .183
811.3 Joining Materials . . . . . . . . . . . . . .183
811.4 Access . . . . . . . . . . . . . . . . . . . . .183
811.5 Permanent Record . . . . . . . . . . . .183
811.6 Chemical Vent . . . . . . . . . . . . . . .183
CMC § 309.0 Medium relevance — show source text
309.0 Workmanship.
309.1 Engineering Practices. Design, construction, and workmanship shall comply with accepted engineering practices and shall be of such character as to secure the results sought to be obtained by this code.
309.2 Concealing Imperfections. It shall be unlawful to conceal cracks, holes, or other imperfections in materials by welding, brazing, or soldering, by using therein or thereon paint, wax, tar, solvent cement, other leak-sealing or repair agent.
309.3 Installation Practices. Mechanical systems shall be installed in a manner that is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All mechanical systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction.
310.0 Condensate Wastes and Control.
310.1 Condensate Disposal. Condensate from air washers, air-cooling coils, condensing appliances, and the overflow from evaporative coolers and similar water-supplied equipment or similar air-conditioning equipment shall be collected and discharged to an approved plumbing fixture or disposal area. Where discharged into the drainage system, equipment shall drain by means of an indirect waste pipe. The waste pipe shall have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope and shall be of approved corrosion-resistant material not smaller than the outlet size in
accordance with Section 310.3 or Section 310.4 for air-cooling coils or condensing appliances, respectively. Condensate or wastewater shall not drain over a public way.
310.1.1 Condensate Pumps. Where approved by the Authority Having Jurisdiction, condensate pumps shall be installed in accordance with the manufacturer’s installation instructions. Pump discharge shall rise vertically to a point where it is possible to connect to a gravity condensate drain and discharged to an approved disposal point. Each condensing unit shall be provided with a separate sump and interlocked with the equipment to prevent the equipment from operating during a failure. Separate pumps shall be permitted to connect to a single gravity indirect waste where equipped with check valves and approved by the Authority Having Jurisdiction.
310.2 Condensate Control. Where any equipment or appliance is installed in a space where damage is capable of resulting from condensate overflow, a drain line shall be provided and shall be drained in accordance with Section 310.1. An additional protection method for condensate overflow shall be provided in accordance with one of the following:
(1) A water level detecting device that will shut off the equipment or appliance in the event the primary drain is
EQUIPMENT CAPACITY IN
TONS OF REFRIGERATIONMINIMUM CONDENSATE
PIPE DIAMETER
(inches)
Up to 203⁄4
21 – 401
41 – 9011⁄4
91 – 12511⁄2
126 – 2502 For SI units: 1 ton of refrigeration = 3.52 kW, 1 inch = 25 mm
CMC § 310.5 Medium relevance — show source text
310.5 Point of Discharge. Air-conditioning condensate waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 310.4.
310.6 Condensate Waste from Air-Conditioning Coils. Where the condensate waste from air-conditioning coils discharges by direct connection to a lavatory tailpiece or to an approved accessible inlet on a bathtub overflow, the connection shall be located in the area controlled by the same person controlling the air-conditioned space. 310.7 Female Plastic Connections. Female plastic screwed fittings shall be used with plastic male fittings and plastic male threads. Female plastic threaded connections shall not be allowed to be used when threaded onto a male
metallic connection.
311.0 Heating or Cooling Air System. 311.1 Source. A heating or cooling air system shall be provided with return air, outside air, or both. A heating or cooling air system regulated by this code and designed to replace required ventilation shall be arranged to discharge into a conditioned space not less than the amount of outside air specified in Chapter 4.
311.2 Air Filters. Air filters shall be installed in a heating, cooling, or makeup air system. Media-type air filters shall comply with UL 900. Electrostatic and high efficiency particulate filters shall comply with Section 935.0.
Exceptions:
(1) Air filters used in systems serving single guest rooms or dwelling units shall not be required to be listed.
(2) Air filters used in listed appliances and in accordance with the manufacturer’s instructions.
311.2.1 Minimum Filtration. In mechanically ventilated buildings, occupied areas of the building shall be provided with air filtration media for outside and return air that provides not less than a Minimum Efficiency Reporting Value (MERV) of 13 or as required by the Authority Having Jurisdiction. Installed filters shall be clearly labeled by the manufacturer indicating the MERV rating.
311.3 Prohibited Sources. Outside or return air for a heating or cooling air system shall not be taken from the following locations:
(1) Less than the separation distances to vents required by Section 802.6.1 and Section 802.8.
(2) Less than the separation distances required by Section 402.4.
(3) A hazardous or insanitary location, or a refrigeration machinery room as defined in this code.
(4) An area, the volume of which is less than 25 percent of the entire volume served by such system, unless there is a permanent opening to an area the volume of which is equal to 25 percent of the entire volume served.
Exception: Such openings where used for a heating or cooling air system in a dwelling unit shall be permitted to be reduced to not less than 50 percent of the required area, provided the balance of the required return air is taken from a room or hall having not less than three doors leading to other rooms served by the furnace.
(5) A closet, bathroom, toilet room, kitchen, garage, boiler room, furnace room, or unconditioned attic.
(6) Rooms or spaces containing a fuel-burning appliance therein. Where such room or space serves as source of return-air.
Exceptions:
CMC § 2.3. Medium relevance — show source text
The reserved pathway and penetrations through the building envelope shall be sized to meet one of the following: i. The reserved pathway and penetrations shall be sized to serve a HPWH system that meets the total building hot water demand as calculated and documented by the responsible person associated with the project. ii. The reserved pathway and penetrations shall be sized to meet the requirements specified in Joint Appendix JA15.2.3.
Condensate drainage piping. An approved receptacle that is sized per the California Plumbing Code for condensate drainage shall be installed within 3 feet of the reserved heat pump location, or piping shall be installed from within 3 feet of the reserved heat pump location to an approved discharge location that is sized in accordance with the California Plumbing Code, and meet one of the following: i. Condensate drainage shall be sized to serve a HPWH system that meets the total building hot water demand as calculated and documented by the responsible person associated with the project. ii. Condensate drainage piping shall be sized to meet the requirements specified in Joint Appendix JA15.2.4.
Electrical.
A. Physical space shall be reserved on the bus system of the main switchboard or on the bus system of a distribution board to serve the future HPWH system, including the heat pump and temperature maintenance tanks. In addition, the physical space reserved shall be capable of providing adequate power to the future heat pump water heater in accordance with the following: i. Heat pump. Meet one of the following: A. The electrical power required to power a HPWH system that meets the total building hot water demand as calculated and documented by the responsible person associated with the project. B. The electrical power required that meets the requirements specified for the heat pump in Joint Appendix JA15.2.5.
ii. Temperature maintenance tank. Meet one of the following: A. The electrical power required to power a HPWH system temperature maintenance tank that meets the total building hot water demand as calculated and documented by the responsible person associated with the project. B. The electrical power required that meets the requirements specified for the temperature maintenance tank in Joint Appendix JA15.2.5.
NOTE: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .
236 2025 CALIFORNIA ENERGY CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
11 MULTIFAMILY BUILDINGS—PERFORMANCE
AND PRESCRIPTIVE COMPLIANCE APPROACHES
SECTION 170.0—GENERAL
Multifamily buildings shall comply with the applicable requirements of Sections 170.0 through 170.2. Sections 170.0 through 170.2 apply to dwelling units and common use areas in multifamily buildings. Nonresidential occupancies in mixed occupancy buildings shall comply with nonresidential requirements in Sections 120, 130, 140 and 141.
CMC § 811.3 Medium relevance — show source text
CPVC pipe and fittings shall comply with ASTM F2618. PP pipe and fittings shall comply with ASTM F1412 or CSA B181.3. PVDF pipe and fittings shall comply with ASTM F1673 or CSA B181.3. Chemical-resistant glass pipe and fittings shall comply with ASTM C1053. High-silicon iron pipe and fittings shall comply with ASTM A861.
811.3 Joining Materials. Joining materials shall be of approved type and quality.
811.4 Access. Where practicable, the piping shall be readily accessible and installed with the maximum of clearance from other services.
811.5 Permanent Record. The owner shall make and keep a permanent record of the location of piping and venting carrying chemical waste.
811.6 Chemical Vent. No chemical vent shall intersect
vents for other services.
811.7 Discharge. Chemical wastes shall be discharged in a manner approved by the Authority Having Jurisdiction.
811.8 Diluted Chemicals. The provisions of this section about materials and methods of construction shall not apply to installations such as photographic or x-ray darkrooms or research or control laboratories where minor amounts of ade quately diluted chemicals are discharged.
812.0 Clear Water Wastes.
812.1 General. Water lifts, expansion tanks, cooling jackets, sprinkler systems, drip or overflow pans, or similar devices that discharge clear wastewater into the building drainage system shall discharge through an indirect waste.
813.0 Swimming Pools.
813.1 General. Pipes carrying wastewater from swimming or wading pools, including pool drainage and backwash from filters, shall be installed as an indirect waste. Where a pump is used to discharge pool waste water to the drainage system, the pump discharge shall be installed as an indirect waste.
814.0 Condensate Waste and Control.
814.1 Condensate Disposal. Condensate from air washers, air-cooling coils, condensing appliances, and the over
2025 CALIFORNIA PLUMBING CODE 183
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
INDIRECT WASTES
flow from evaporative coolers and similar water-supplied equipment or similar air-conditioning equipment shall be collected and discharged to an approved plumbing fixture or disposal area. Where discharged into the drainage system, equipment shall drain using an indirect waste pipe. The waste pipe shall have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope and shall be of an approved corrosion-resistant material not smaller than the outlet size in
accordance with Section 814.3 or Section 814.4 for air-cooling coils or condensing appliances, respectively. Condensate or wastewater shall not drain over a public way.
814.1.1 Condensate Pumps. Where approved by the Authority Having Jurisdiction, condensate pumps shall be installed in accordance with the manufacturer’s instal lation instructions. Pump discharge shall rise vertically to a point where it is possible to connect to a gravity condensate drain and discharged to an approved disposal point. Each condensing unit shall be provided with a separate sump and interlocked with the equipment to prevent the equipment from operating during a failure. Separate pumps shall be permitted to connect to a single gravity indirect waste where equipped with check valves and approved by the Authority Having Jurisdiction.
CMC § 808.0 Medium relevance — show source text
808.0 Cooling Water . . . . . . . . . . . . . . . .182
808.1 General . . . . . . . . . . . . . . . . . . . . .182
809.0 Drinking Fountains . . . . . . . . . . . .182
809.1 General . . . . . . . . . . . . . . . . . . . . .182
810.0 Steam and Hot Water Drainage Condensers and Sumps . . . . . . . .182
810.1 High-Temperature Discharge . . . .182
Table 810.1 Pipe Connections in Blowoff Condensers and Sumps . . . . . . . .183
810.2 Sumps, Condensers, and Intercepting Tanks . . . . . . . . . . . .183
810.3 Cleaning . . . . . . . . . . . . . . . . . . . .183
810.4 Strainers . . . . . . . . . . . . . . . . . . . .183
811.0 Chemical Wastes . . . . . . . . . . . . .183
811.1 Pretreatment . . . . . . . . . . . . . . . . .183
811.2 Waste and Vent Pipes . . . . . . . . .183
811.3 Joining Materials . . . . . . . . . . . . . .183
811.4 Access . . . . . . . . . . . . . . . . . . . . .183
811.5 Permanent Record . . . . . . . . . . . .183
811.6 Chemical Vent . . . . . . . . . . . . . . .183
811.7 Discharge . . . . . . . . . . . . . . . . . . .183
811.8 Diluted Chemicals . . . . . . . . . . . . .183
812.0 Clear Water Wastes . . . . . . . . . . .183
812.1 General . . . . . . . . . . . . . . . . . . . . .183
813.0 Swimming Pools . . . . . . . . . . . . . .183
813.1 General . . . . . . . . . . . . . . . . . . . . .183
814.0 Condensate Waste and Control . . .183
814.1 Condensate Disposal . . . . . . . . . .183
814.2 Condensate Control . . . . . . . . . . .184
814.3 Condensate Waste Pipe Material and Sizing . . . . . . . . . . . .184
Table 814.3 Minimum Condensate Pipe Size . . . . . . . . . . . . . . . . . . .184
814.4 Appliance Condensate Drains . . .184
814.5 Point of Discharge . . . . . . . . . . . .184
814.6 Condensate Waste from
Air-Conditioning Coils . . . . . . . . . .185
814.7 Plastic Fittings . . . . . . . . . . . . . . .185
xxxvi 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
TABLE OF CONTENTS
Frequently asked questions
When must condensate be discharged indirectly (air gap/air break)?
Condensate that enters the drainage system from air‑conditioning coils or similar equipment must connect indirectly through an air gap or air break to a trapped and vented receptor (mop sink, dry well, approved plumbing fixture, etc.) unless code or the appliance instructions allow a specific direct connection; see CMC § 310.5 and CPC § 814.5 for the applicable requirements.
What overflow protection is required for condensate pans?
Where condensate overflow could cause damage, the code requires a drain and additional protection such as a water‑level shutoff, secondary watertight pan with separate drain, or elevated secondary drain — see CMC § 310.2 and CPC § 814.2 for the listed options and minimum drain size for the secondary pan.
How are condensate drain piping materials and sizes determined?
Minimum condensate pipe diameters are specified based on equipment capacity (see CMC Table § 310.3 / CPC Table § 814.3). Materials must be corrosion‑resistant and approved for the liquid discharged; larger air‑conditioning waste pipes (≥ 1¼") must follow plumbing code materials. Cleanouts and slope (minimum 1% unless approved otherwise) are also required.
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