CPC · California Plumbing Code

How must condensate be disposed of and what are the rules for condensate pumps?

Condensate from air‑conditioning and condensing equipment must be collected and drained to an approved receptacle (not onto public ways) and — if routed into the drainage system — must go through an indirect waste pipe at a minimum slope of 1/8 inch per foot. Condensate pumps are allowed only with AHJ approval, must be installed per the manufacturer, must lift only to a gravity tie point, and each condensing unit needs its own sump and interlock to prevent operation if the pump fails (multiple pumps to one gravity line require check valves and AHJ approval). **See § 814.1 and § 814.1.1**.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

Condensate from air washers, air‑cooling coils, condensing appliances, and similar equipment must be collected and discharged to an approved plumbing fixture or disposal area and, when routed into the drainage system, must do so by an indirect waste pipe with a slope of not less than 1/8 inch per foot (1%), and made of corrosion‑resistant material not smaller than the outlet size — see § 814.1.

When a condensate pump is used, it must be installed per the manufacturer and — where permitted by the Authority Having Jurisdiction (AHJ) — the pump discharge must rise vertically to a point where it can connect to a gravity condensate drain; each condensing unit must have a separate sump and be interlocked to prevent equipment operation on pump failure (exceptions for multiple pumps tying to a single gravity indirect waste require check valves and AHJ approval) — see § 814.1.1.

The single most important rule: always collect condensate and discharge it indirectly; if you use a pump, it must lift only to the nearest gravity connection and each unit must have its own protected sump or approved interlock. § 814.1 and § 814.1.1 control this.

Requirements in detail

Where condensate must go (basic path)

Collect and discharge condensate to an approved plumbing fixture or disposal area (not over a public way) — § 814.1.
If routed into the drainage system it must be by an indirect waste pipe (air gap/air break per related sections). § 814.1.

Minimum slope and pipe material/size

Minimum slope: 1/8 inch per foot (10.4 mm/m) or 1 percent. § 814.1.
Pipe material: approved corrosion‑resistant material, and not smaller than the outlet size (see § 814.3 for additional material/size requirements). § 814.1.

Condensate pump rules (when pumps are used)

Pumps allowed only where approved by the Authority Having Jurisdiction (AHJ). § 814.1.1.
Pumps must be installed in accordance with the manufacturer’s installation instructions. § 814.1.1.
Pump discharge shall rise vertically to a point where it is possible to connect to a gravity condensate drain and then discharge to an approved disposal point. § 814.1.1.
Each condensing unit must have a separate sump and the sump/pump must be interlocked with the equipment so the equipment cannot operate if pump/sump fails. § 814.1.1.
Multiple pumps may tie into a single gravity indirect waste only if equipped with check valves and approved by the AHJ. § 814.1.1.

Drain configuration, traps, cleanouts and point of discharge

Condensate drains must be configured or provided with a cleanout to allow clearing without cutting the line (see § 814.3.1).
Individual condensate drains shall be trapped per manufacturer instructions or per § 814.4.
Condensate must discharge indirectly to trapped/vented receptors (dry wells, mop sinks, leach pits, tailpiece of fixtures) — § 814.5.

Decision table — key dimensions/values

Decision dimension	Value / threshold	Code Reference
Minimum slope for condensate waste	1/8 inch per foot (≈ 1%)	§ 814.1
Minimum material requirement	Approved corrosion‑resistant material; not smaller than outlet	§ 814.1
Pump installation authority	Only where approved by AHJ; follow manufacturer	§ 814.1.1
Pump discharge routing	Must rise vertically to tie into gravity condensate drain	§ 814.1.1
Sump requirement per condensing unit	Separate sump + interlock to prevent operation on failure	§ 814.1.1
Multiple pumps to one drain	Allowed if check valves used and AHJ approval	§ 814.1.1
Minimum condensate pipe size by equipment capacity	See Table (next row)	Table 814.3 / § 814.3
Cleanouts required	Drain lines must be provided/configured with cleanouts	§ 814.3.1

Table 814.3 — Minimum condensate pipe sizes (decision‑relevant excerpt)

Equipment capacity (tons refrigeration)	Minimum condensate pipe diameter
Up to 20	3/4 inch
21 – 40	1 inch
41 – 90	1‑1/4 inch
91 – 125	1‑1/2 inch
126 – 250	2 inch
Code reference: Table 814.3 / § 814.3

(Condensate drain sizing assumes the 1/8 inch per foot slope and pipe running three‑quarters full; different slopes/conditions require AHJ approval — § 814.3.)

Exceptions & special cases

Condensate pumps are only permitted when approved by the AHJ; if the AHJ does not approve pumps, gravity/indirect waste routing is required. § 814.1.1.
Multiple pumps may share a gravity indirect waste only with check valves and AHJ approval — § 814.1.1.
Condensate waste piping less than 1‑1/4 inch may use approved plastics (PVC, CPVC, PE, PP) or copper where allowed; piping 1‑1/4 inch and larger must be constructed of materials specified in Chapter 7 — see § 814.3.
If condensate discharge could cause damage from overflow, additional protection (water level detection to shut off equipment, secondary pans with separate drains, or elevated secondary drain connection) is required — see § 814.2.

Common mistakes

Allowing condensate to drain over a public way — expressly prohibited in § 814.1.
Routing condensate directly into the building drain without an indirect waste (air gap/air break) when required — see § 814.1 and § 814.5.
Using undersized condensate piping (ignore Table 814.3) or failing to maintain the 1/8 inch per foot slope — sizing and slope are linked in § 814.1 and Table 814.3.
Installing a condensate pump without interlocks (so equipment keeps running when pump fails) or without separate sumps for each condensing unit — both required by § 814.1.1.
Connecting multiple pumps to a single gravity drain without check valves and AHJ approval — prohibited unless both conditions are met (see § 814.1.1).
Omitting cleanouts in condensate drain lines (makes maintenance difficult) — required by § 814.3.1.

Worked example — concrete scenario

Scenario: A commercial rooftop condensing unit has a capacity of 30 tons and cannot reach a gravity drain without a pump.

Sizing the condensate drain: For 30 tons you use the table size 1 inch minimum (Table 814.3). § 814.3 / Table 814.3.
Slope requirement: Any gravity portions of the condensate waste must be installed with 1/8 inch per foot slope. § 814.1.
Pump installation: Because the unit cannot gravity‑drain, you may use a condensate pump if the AHJ approves. Install the pump per the manufacturer’s instructions, and route the pump discharge vertically up to the elevation where it can tie into the 1‑inch gravity condensate drain. § 814.1.1.
Sump and interlock: Provide a separate sump for this condensing unit and interlock the unit so that the condensing equipment cannot operate if the sump/pump fails. § 814.1.1.
Point of discharge: Tie the gravity condensate drain indirectly into an approved receptor (e.g., mop sink or trapped receptor) with an air gap/air break per § 814.5. § 814.5.

If there were two identical rooftop units each with their own pump, you could only tie both pumps to the same gravity indirect waste if each pump discharge had a check valve and the AHJ approved that arrangement — § 814.1.1.

Related provisions

§ 814.2 — Condensate control (overflow protection options: water‑level shutoff, secondary pans, elevated secondary drain).
§ 814.3 & Table 814.3 — Condensate waste pipe material and sizing (minimum sizes by equipment capacity).
§ 814.3.1 — Cleanouts for condensate drain lines.
§ 814.4 — Appliance condensate drains; traps / protection where multiple appliances connect.
§ 814.5 — Point of discharge (indirect connections to receptors).
§ 814.6 — Condensate waste from air‑conditioning coils (area control for lavatory tailpiece connections).
§ 814.7 — Plastic fittings guidance.

Code references

Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:

CPC § 814.0 High relevance — show source text
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

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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.

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.
CPC § 309.0 High 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 REFRIGERATION MINIMUM CONDENSATE
PIPE DIAMETER
(inches)

Up to 20 3⁄4

21 – 40 1

41 – 90 11⁄4

91 – 125 11⁄2

126 – 250 2

For SI units: 1 ton of refrigeration = 3.52 kW, 1 inch = 25 mm
CPC § 811.3 High 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

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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.
CPC § 307.4 High relevance — show source text
(11)Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

An appliance shall be accompanied by clear and complete installation instructions, including required clearances from combustible other than mounting or adjacent surfaces, and temperature rating of field-installed wiring connections exceeding 140°F (60°C). 307.4 Absorption Units. Absorption units shall bear a permanent and legible factory-applied nameplate on which shall

appear:

(1) The name or trademark of the manufacturer.

(2) The model number or equivalent.

(3) The serial number.

(4) The amount of refrigerant.

(5) The refrigerant designation.

(6) Hourly rating in Btu/h (kW).

(7) The type of fuel approved for use with the unit.

(8) Cooling capacity Btu/h (kW).

(9) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

(10)The symbol of an approved agency certifying compliance of the equipment with recognized standards.

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GENERAL REGULATIONS

308.0 Improper Location.

308.1 General. Piping or equipment shall not be so located as to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.

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.
CPC § 310.1.1 High relevance — show source text
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 REFRIGERATION MINIMUM CONDENSATE
PIPE DIAMETER
(inches)

Up to 20 3⁄4

21 – 40 1

41 – 90 11⁄4

91 – 125 11⁄2

126 – 250 2

For SI units: 1 ton of refrigeration = 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

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
CPC § 814.3.1 High relevance — show source text
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 Chapter 7. 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.

814.3.1 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. 814.4 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. 814.5 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 814.4.

TABLE 814.3

MINIMUM CONDENSATE PIPE SIZE

For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm

For SI units: °C = (°F-32)/1.8

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INDIRECT WASTES

814.6 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. 814.7 Plastic Fittings. Female plastic screwed fittings shall be used with male plastic fittings and plastic threads.

2025 CALIFORNIA PLUMBING CODE 185

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CHAPTER 9 - VENTS

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CPC § 811.7 High relevance — show source text
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

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TABLE OF CONTENTS

CHAPTER 9 VENTS . . . . . . . . . . . . . . . . . . . . .187

901.0 General . . . . . . . . . . . . . . . . . . . . .189

901.1 Applicability . . . . . . . . . . . . . . . . . .189

901.2 Vents Required . . . . . . . . . . . . . . .189

901.3 Trap Seal Protection . . . . . . . . . . .189

902.0 Vents Not Required . . . . . . . . . . .189

902.1 Interceptor . . . . . . . . . . . . . . . . . .189

902.2 Bars, Soda Fountains, and Counter . . . . . . . . . . . . . . . . . . . . .189

903.0 Materials . . . . . . . . . . . . . . . . . . . .189

903.1 Applicable Standards . . . . . . . . . .189

903.2 Use of Copper or Copper Alloy Tubing . . . . . . . . . . . . . . . . .189

903.3 Changes in Direction . . . . . . . . . .189

904.0 Size of Vents . . . . . . . . . . . . . . . .189

904.1 Size . . . . . . . . . . . . . . . . . . . . . . . .189

904.2 Length . . . . . . . . . . . . . . . . . . . . . .189

CPC § 1001.4. Medium relevance — show source text

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HYDRONICS

»

shall drain by indirect waste in accordance with Section 1001.4. Embedded piping underground or under floors is not required to be designed for draining the system.

1221.5 Condensate Drainage. Condensate drains from dehumidifying coils shall be constructed and sloped for condensate removal. Such drains shall be installed in accordance

with Section 310.0.

1221.6 Hydronic Fluid Disposal. Hydronic system fluids that contain additives such as antifreeze, corrosion inhibitors, and cleaning solutions shall be recycled or disposed of in an approved manner in accordance with Environmental Protection Agency (EPA), the Department of Health, and as required by the Authority Having Jurisdiction.

1221.7 Clearance to Combustibles. Hydronic piping where the exterior temperature exceeds 250°F (121°C) shall have a clearance of not less 1 inch (25.4 mm) to combustible materials.

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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 13 – FUEL GAS PIPING

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
Adopt Entire Chapter	X		X	X	X			X		X	X	X	X	X	X	X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter/Section

CPC § 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
CPC § 305.6 Medium 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

2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

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
CPC § 910.0 Medium relevance — show source text
Combination waste

and vent piping . . . . . . . . . . . . . . . . .910.0, Appendix B Combustion air openings . . . . . . . . . . . . .506.3 – 506.5 Condensate pipe . . . . . . . . . . . . . . . .814.3, Table 814.3 Disposal fields . . . . . . . . . . . . . . . . . . . . . . .Appendix H Drainage piping . . . . . . . . . . . . . . . .Table 702.1, 703.0, Table 703.2, C 304.0,

E 302.2, E 504.4

FOG disposal systems . . . . . . . . . . . . . . . . . . . . .1015.3

Fuel gas piping systems . . . . . .1208.3, 1214.0, 1215.0,

E 403.2, Table E 403.2

Fuel gas vents . . . . . . . . . . . . . . . . . . .509.6.2, 509.7.4,

509.10.2, 510.0

Flushometer valves and tanks . . . . . . . . .610.10, 610.11

Gray water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1503.8

Grease interceptors . . . . . . . . .1014.2.1, Table 1014.2.1,

1014.3.6, Table 1014.3.6

Hanger rods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .313.6

Indirect waste pipes . . . . . . . . . . . . . . . . .801.3.1, 803.3

Leaders, conductors,

and storm drains . . . . . . . . . . .1103.0, Table 1103.1,

Table 1103.2, Table 1103.3

Louvers, grilles, and screens . . . . . . . . . . . . . . . . .506.8

Medical gas and medical vacuum pipe . . . . . . .1323.1.1

Mulch basins . . . . . . . . . . . . . . . . . . . . . . . . . .1504.5.1

Oil tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E 403.12

Pipe cleanouts . . . . . . . . . . . . . . . . .Table 707.1, 707.10

Rainwater catchment systems . . . . . . . .1602.6, K 106.5

Reclaimed (recycled)

water piping . . . . . . . . . . . . . . . . . . . . . . . . . . .1502.6

Roof drainage . . . . . . . . . . . . . . . .1101.12, Table 1103.2,

Table 1103.3, 1105.1,

1603.15, Appendix D, K 106.4
CPC § 310.1 Medium 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

2025 CALIFORNIA MECHANICAL CODE

316.0 Protection of Piping, Tubing, Materials, and Structures . . . . . . . . 59

316.1 General. . . . . . . . . . . . . . . . . . . . . . 59

Frequently asked questions

Can condensate be discharged outside onto the sidewalk or gutter?

No. Condensate or wastewater shall not drain over a public way; it must be directed to an approved disposal point or indirect waste receptor per § 814.1.

Do condensate pumps require AHJ approval?

Yes. Condensate pumps are allowed where approved by the Authority Having Jurisdiction and must be installed per the manufacturer; see § 814.1.1.

Must each condensing unit have its own sump?

Yes. Each condensing unit shall be provided with a separate sump and the sump/pump must be interlocked with the equipment to prevent operation on pump failure — § 814.1.1.

Can two pumps discharge into the same gravity indirect waste?

Only if the pump discharges are equipped with check valves and the arrangement is approved by the AHJ — § 814.1.1.

What slope and material should I use for condensate drain piping?

Use a minimum slope of 1/8 inch per foot (1%), and piping must be an approved corrosion‑resistant material not smaller than the outlet size; see § 814.1 and § 814.3.

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California Plumbing Code