Chapter 9 — INSTALLATION OF SPECIFIC APPLIANCES

(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.)

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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

CHAPTER 9

INSTALLATION OF SPECIFIC APPLIANCES

the design, construction, and installation of specific appliances. In addition to the requirements of this chapter, appliances shall comply with the general requirements of Chapter 3.

This chapter is applicable primarily to nonindustrial-type appliances and installations and, unless specifically indicated, does not apply to industrial-type appliances and installations. Listed appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions or, as elsewhere specified in this chapter, as applicable to the appliance. Unlisted appliances shall be installed as specified in this part as applicable to the appliances.

Appliances shall not be installed so their combustion, ventilation, and dilution air are obtained only from a bedroom or bathroom unless the bedroom or bathroom has the required volume in accordance with Section 701.4. [NFPA 54:10.1.2]

[OSHPD 1, 1R, 2, 4 & 5] Warm air furnaces shall not be installed under openable windows on exterior walls.

When additional or replacement appliances or equipment is installed or an appliance is converted to gas from another fuel, the location in which the appliances or equipment is to be operated shall be checked to verify the following:

(1) Air for combustion and ventilation is provided where required, in accordance with the provisions of Section 701.0. Where existing facilities are not adequate, they shall be upgraded to meet Section 701.0 specifications.

(2) The installation components and appliances meet the clearances to combustible material provisions of Section 303.10. It shall be determined that the installation and operation of the additional or replacement appliances do not render the remaining appliances unsafe for continued operation.

(3) The venting system is constructed and sized in accordance with the provisions of Section 802.0. Where the existing venting system is not adequate, it shall be upgraded to comply with Section 802.0. [NFPA 54:9.1.2]

the fuel gas for which it was designed. No attempt shall be made to convert the appliance from the gas specified on the rating plate for use with a different gas without consulting the installation instructions, the serving gas supplier, or the appliance manufacturer for complete instructions. Listed appliances shall not be converted unless permitted by and in accordance with the manufacturer’s installation instructions. [NFPA 54:9.1.3]

Appliances Used Indoors. Unlisted appliances for use

with undiluted LP-Gases and installed indoors, except attended laboratory equipment, shall be equipped with safety shutoff devices of the complete shutoff type. [NFPA 54:9.1.4]

shall not be increased or decreased in violation of the approved rating at the altitude where it is being used.

or oxygen under pressure is used in connection with the gas supply, effective means such as a back pressure regulator and relief valve shall be provided to prevent air or oxygen from passing back into the gas piping. Where oxygen is used, installation shall be in accordance with NFPA 51. [NFPA 54:9.1.5]

shall be furnished either with load-distributing bases or with a sufficient number of supports to prevent damage to either the building structure or the appliance and the equipment.

[NFPA 54:9.1.8.1] 902.8.1 Structural Capacity. At the locations selected for installation of appliances and equipment, the dynamic and static load-carrying capacities of the building structure shall be checked to determine whether they are adequate to carry the additional loads. The appliances and equipment shall be supported and shall be connected to the piping so as not to exert undue stress on the connections. [NFPA 54:9.1.8.2]

installed in areas where the open use, handling, or dispensing of flammable liquids occurs, unless the design, operation, or installation reduces the potential of ignition of the flammable vapors. Appliances installed in compliance with Section 305.1 through Section 305.1.2, Section 303.11, or Section 303.12 shall be considered to comply with the intent of this provision. [NFPA 54:9.1.9]

Unless otherwise specified, solid-fuel-burning appliances shall be installed in accordance with NFPA 211 and the manufacturer’s instal lation instructions.

Any combination of appliances, equipment, attachments, or devices used together in any manner shall comply with the standards that apply to the individual appliance and equipment. [NFPA 54:9.1.19]

Gases Other than Products of Combustion. Nondirect-vent appliances installed in beauty shops, barber shops, or other facilities where chemicals that generate corrosive or flammable products such as aerosol sprays are routinely used shall be located in a mechanical room separate or partitioned off from other areas with provisions for combustion and dilution air from outdoors. Direct vent appliances in such facilities shall be in accordance with the appliance manufacturer’s installation instructions. [NFPA 54:9.1.6.2]

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INSTALLATION OF SPECIFIC APPLIANCES

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903.2.3 Connection of Gas Engine-Powered Air Conditioners. Gas engines shall not be rigidly connected to the gas supply piping. [NFPA 54:10.2.3]

903.2.4 Clearances for Indoor Installation. The installation of air-conditioning appliances shall comply with the following requirements:

(1) Air-conditioning appliances shall be installed with clearances in accordance with the terms of their listing and the manufacturer’s instructions. {NFPA 54:10.2.4(1)}

(2) Air-conditioning appliances shall be permitted to be installed with reduced clearances to combustible material, provided that the combustible material or appliance is protected as described in Table 303.10.1 and such reduction is allowed by the manufacturer’s installation instructions. [NFPA 54:10.2.4(2)]

(3) Where the furnace plenum is adjacent to plaster on metal lath or noncombustible material attached to

combustible material, the clearance shall be measured to the surface of the plaster or other noncombustible finish where the clearance specified is 2 inches (51 mm) or less. [NFPA 54:10.2.4(3)]

(4) Air-conditioning appliances shall have the clearance from supply ducts within 3 feet (914 mm) of the furnace plenum be not less than that specified from the furnace plenum. No clearance is necessary beyond this distance. [NFPA 54:10.2.4(4)]

903.2.5 Assembly and Installation. Unless the airconditioning appliance is listed for installation on a combustible surface, or unless the surface is protected in an approved manner, it shall be installed on a surface of noncombustible construction with noncombustible mate rial and surface finish and with no combustible material against the underside thereof. [NFPA 54:10.2.5]

903.2.6 Refrigeration Coils. The installation of refrigeration coils shall be in accordance with Section 904.8 and Section 904.9. [NFPA 54:10.2.7]

903.2.7 Switches in Electrical Supply Line. Means for interrupting the electrical supply to the air-conditioning appliance and to its associated cooling tower shall be in accordance with NFPA 70. [NFPA 54:10.2.8]

terminal air conditioners and heat pumps shall comply with UL 484 or UL 60335-2-40, and shall be installed in accordance with the manufacturer’s installation instructions.

shall be listed in accordance with the following:

(1) Central heating furnaces and boilers having input ratings up to and including 400 000 Btu/hr (117 kW) shall be listed in accordance with the following as applicable:

(a) Furnaces listed in accordance with CSA/ANSI Z21.47/CSA 2.3.

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tion in commercial or industrial processes, process air shall be provided as required for cooling of appliances, equipment, or material; for controlling dew point, heating, drying, oxidation, dilution, safety exhaust, odor control, and air for compressors; and for comfort and proper working conditions for personnel. [NFPA 54:9.1.7]

gas supply pressure is higher than that at which the appliance is designed to operate or varies beyond the design pressure limits of the appliance, a gas appliance pressure regulator listed in accordance with CSA/ANSI Z21.18/CSA 6.3 shall

be installed. [NFPA 54:9.1.17]

lines shall comply with the following requirements:

(1) Diaphragm-type valves shall be equipped to convey bleed gas to the outdoors or into the combustion chamber adjacent to a continuous pilot.

(2) In the case of bleed lines leading outdoors, means shall be employed to prevent water from entering this piping and also to prevent blockage of vents by insects and foreign

matter.

(3) Bleed lines shall not terminate in the appliance flue or exhaust system.

(4) In the case of bleed lines entering the combustion chamber, the bleed line shall be located so the bleed gas is readily ignited by the pilot and the heat liberated thereby does not adversely affect the normal operation of the safety shutoff system. The terminus of the bleed line shall be securely held in a fixed position relative to the pilot. For manufactured gas, the need for a flame arrester in the bleed line piping shall be determined.

(5) A bleed line(s) from a diaphragm-type valve and a vent line(s) from an appliance pressure regulator shall not be connected to a common manifold terminating in a combustion chamber. Bleed lines shall not terminate in positive-pressure-type combustion chambers. [NFPA 54:9.1.18]

systems designed for permanent installation shall comply with UL 1995 or UL 60335-2-40.

Gas-fired air conditioners shall comply with Section 903.2.1 through Section 903.2.7.

903.2.1 Application. Gas-fired air conditioners and heat pumps shall be listed in accordance with ANSI Z21.40.1/CGA 2.91 or ANSI Z21.40.2/CGA 2.92.

[NFPA 54:10.2.1]

903.2.2 Independent Gas Piping. Gas piping serving heating appliances shall be permitted to also serve cooling appliances where heating and cooling appliances cannot be operated simultaneously. [NFPA 54:10.2.2]

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INSTALLATION OF SPECIFIC APPLIANCES

904.3.3 Listed and Unlisted Units. Central heating furnaces and low-pressure boilers shall be permitted to be installed with reduced clearances to combustible material, provided that the combustible material or appliance is protected as described in Table 303.10.1 and Figure 303.10.1(1) through Figure 303.10.1(3), and such reduction is allowed by the manufacturer’s installation instructions. [NFPA 54:10.3.3.3]

904.3.4 Front Clearance. Front clearance shall be sufficient for servicing the burner and the furnace or boiler.

[NFPA 54:10.3.3.4]

904.3.5 Adjacent to Plaster or Noncombustible Materials. Where the furnace plenum is adjacent to plaster on metal lath or noncombustible material attached to combustible material, the clearance shall be measured to the surface of the plaster or other noncombustible finish where the clearance specified is 2 inches (51 mm) or less. [NFPA 54:10.3.3.5]

904.3.6 Interference. The clearances to these appliances shall not interfere with combustion air, draft hood clearance and relief, and accessibility for servicing.

[NFPA 54:10.3.3.6] 904.3.7 Central Heating Furnaces. Central heating furnaces other than those listed in Section 603.13.2 or Section 603.13.3 shall have clearances from the supply ducts of not less than 18 inches (457 mm) from the furnace plenum for the first 3 feet (914 mm), then 6 inches (152 mm) for the next 3 feet (914 mm) and 1 inch (25.4 mm) beyond 6 feet (1829 mm). [NFPA 54:10.3.3.9]

boiler or furnace shall be installed in accordance with the manufacturer’s instructions in one of the following manners:

(1) On a floor of noncombustible construction with noncombustible flooring and surface finish and with no combustible material against the underside thereof.

(2) On fire-resistive slabs or arches having no combustible material against the underside thereof.

Exceptions:

(1) Appliances listed for installation on a combustible floor.

(2) Installation on a floor protected in an approved manner.

[NFPA 54:10.3.4]

904.4.1 Under-Floor Installation. Furnaces installed in an under-floor area of the building shall be in accordance with the Section 904.4.1.1 through Section 904.4.1.3.

904.4.1.1 Supported by Ground. Where a furnace is supported by the ground, it shall be installed on a concrete slab not less than 3 inches (76 mm) above the adjoining ground level.

904.4.1.2 Supported from Above. Where a furnace is supported from above, a clearance of not less than 6 inches (152 mm) shall be provided from finished grade.

904.4.1.3 Excavation. Where excavation is necessary to install a furnace, it shall be installed in accordance with Section 303.11.

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(b) Low-pressure boilers listed in accordance with ANSI Z21.13/CSA 4.9. [NFPA 54:10.3.1.1]

(2) Furnaces and boilers having input ratings greater than 400 000 Btu/hr (117 kW) shall be listed or in accordance with Section 904.1(2)(a) and Section 904.1(2)(b). [NFPA 54:10.3.1.2]

(a) Acceptance of unlisted appliances, equipment, and accessories shall be on the basis of engineering methods. [NFPA 54:9.1.1.2]

(b) The unlisted appliance, equipment, or accessory shall be safe and suitable for the proposed service and shall be recommended for the service by the manufacturer. [NFPA 54:9.1.1.3]

boiler installations in bedrooms or bathrooms shall comply with one of the following:

(1) Central heating furnaces and low-pressure boilers shall be permitted to be installed in a closet located in the bedroom or bathroom, provided the closet is equipped with a listed, gasketed door assembly, and a listed self-closing device. The self-closing door assembly shall comply with the requirements of Section 904.2.1. The door assembly shall be installed with a threshold and bottom door seal and shall comply with the requirements of Section 904.2.2. Combustion air for such installations shall be

obtained from the outdoors. The closet shall be for the exclusive use of the central heating furnace or low-pressure boiler.

(2) Central heating furnaces and low-pressure boilers shall be of the direct vent type.

904.2.1 Self-Closing Doors. Self-closing doors shall swing easily and freely, and shall be equipped with a self-closing device to cause the door to close and latch each time it is opened. The closing mechanism shall not have a hold-open feature.

904.2.2 Gasketing. Gasketing on gasketed doors or frames shall be furnished in accordance with the published listings of the door, frame, or gasketing material manufacturer.

Exception: Where acceptable to the Authority Having Jurisdiction, gasketing of noncombustible or limitedcombustible material shall be permitted to be applied to the frame, provided closing and latching of the door are not inhibited.

Central heating furnaces and low-pressure boilers shall be provided with clearances in accordance with Section 904.3.1 through Section 904.3.7.

904.3.1 Listed Units. Listed central heating furnaces and low-pressure boilers shall be installed with clearances in accordance with the terms of their listings and the manufacturer’s installation instructions. {NFPA 54:10.3.3.1}

904.3.2 Unlisted Units. Unlisted central heating furnaces and low-pressure boilers shall be installed with clearances from combustible material not less than those specified in Table 904.3.2. [NFPA 54:10.3.3.2]

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INSTALLATION OF SPECIFIC APPLIANCES

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Steam and hot water boilers, respectively, shall be provided with approved automatic limiting devices for shutting down the burner(s) to prevent boiler steam pressure or boiler water temperature from exceeding the maximum allowable working pressure or temperature. Safety limit controls shall not be used as operating controls. [NFPA 54:10.3.5]

All water boilers and steam boilers shall be provided with an automatic means to shut off the fuel supply to the burner(s) if the boiler water level drops below the lowest safe water line. In lieu of the low-water cutoff, water tube or coil-type boilers that require forced circulation to prevent overheating and failure shall have an approved flow sensing device arranged to shut down the boiler when the flow rate is inadequate to protect the boiler against overheating. [NFPA 54:10.3.6]

and hot water boilers shall be equipped, respectively, with listed or approved steam safety or pressure relief valves of appropriate discharge capacity and conforming with ASME requirements. A shutoff valve shall not be placed between the relief valve and the boiler or on discharge pipes between such valves and the atmosphere. [NFPA 54:10.3.7]

904.7.1 Discharge. Relief valves shall be piped to discharge near the floor. [NFPA 54:10.3.7.1]

904.7.2 Size. The entire discharged piping shall be at least the same size as the relief valve discharge piping.

[NFPA 54:10.3.7.2]

904.7.3 End Connections. Discharge piping shall not contain threaded end connection at its termination point.

[NFPA 54:10.3.7.3]

The installation of refrigeration coils shall comply with the following requirements:

(1) A refrigeration coil shall not be installed in conjunction with a forced air furnace where circulation of cooled air is provided by the furnace blower, unless the blower has

sufficient capacity to overcome the external static pressure resistance imposed by the duct system and refrigeration coil at the air flow rate for heating or cooling, whichever is greater.

(2) Furnaces shall not be located upstream from refrigeration coils, unless the refrigeration coil is designed or equipped so as not to develop excessive temperature or

pressure.

(3) Refrigeration coils shall be installed in parallel with or on the downstream side of central furnaces to avoid condensation in the heating element, unless the furnace has been specifically listed for downstream installation. With a parallel flow arrangement, the dampers or other means used to control flow of air shall be sufficiently tight to prevent any circulation of cooled air through the furnace.

(4) Means shall be provided for disposal of condensate and to prevent dripping of condensate on the heating element.

[NFPA 54:10.3.9]

Boilers, where used in conjunction with refrigeration systems, shall be installed so that the chilled medium is piped in parallel with the heating boiler with appropriate valves to prevent the chilled medium from entering the heating boiler.

[NFPA 54:10.3.10.1]

904.9.1 Exposed to Refrigerated Air Circulation. Where hot water heating boilers are connected to heating coils located in air-handling units where they can be exposed to refrigerated air circulation, such boiler piping systems shall be equipped with flow control valves or other automatic means to prevent gravity circulation of the boiler water during the cooling cycle. [NFPA 54:10.3.10.2]

Upright furnaces shall be permitted to be installed in an attic, furred, or under-floor space exceeding 5 feet (1524 mm) in height, provided the required listings and furnace and duct clearances

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For SI units: 1 inch = 25.4 mm, °C = (°F-32)/1.8, 1 pound-force per square inch = 6.8947 kPa

• See Section 904.0 for additional requirements for central heating boilers and furnaces.

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INSTALLATION OF SPECIFIC APPLIANCES

also be handled by a duct(s) sealed to the furnace casing and terminating outside the space containing the furnace. The duct furnace shall be installed on the positive-pressure side of the circulating air blower. [NFPA 54:10.9.6]

tems. A duct furnace shall not be installed in conjunction with a refrigeration coil where circulation of cooled air is provided by the blower.

Exception: Where the blower has sufficient capacity to overcome the external static resistance imposed by the duct system, the furnace, and the cooling coil and the air throughput necessary for heating or cooling, whichever is greater. [NFPA 54:10.9.7.1]

905.7.1 In Conjunction with Cooling Appliances. Duct furnaces used in conjunction with cooling appliances shall be installed in parallel with or on the upstream side of cooling coils to avoid condensation within heating elements. With a parallel flow arrangement, the dampers or other means used to control the flow of air shall be sufficiently tight to prevent any circulation of cooled air through the unit.

Exception: Where the duct furnace has been specifically listed for downstream installation. [NFPA 54:10.9.7.2]

905.7.2 Heat Exchangers. Where a duct furnace is installed downstream of an evaporative cooler or air washer, the heat exchanger shall be constructed of corrosion-resistant materials. Air washers operating with chilled water that deliver air below the dew point of the ambient air at the duct furnace shall be considered as refrigeration systems. [NFPA 54:10.9.7.3]

Hangars. Duct furnaces installed in garages for more than three motor vehicles or in aircraft hangars shall be installed in accordance with Section 303.11 and Section 303.12. [NFPA 54:10.9.8]

within an air duct shall be listed and labeled in accordance with UL 1996 and designed for the maximum air temperature. The duct heater and fan shall be interlocked such that the electric duct heater operates when the fan is operating.

905.9.1 Installation. Duct heaters shall be installed in

accordance with the manufacturer’s installation instructions, and shall not create a hazard to persons or property. Where installed 4 feet (1219 mm) or less from a heat pump or air conditioner, the duct heater shall be listed for such installation.

905.9.2 Clearance. A working space clearance shall be maintained to permit replacement of controls and heating elements and for adjusting and cleaning of controls. The working space for energized equipment shall comply with the California Electrical Code .

Floor furnaces shall be listed in accordance with ANSI Z21.86/CSA 2.32. [NFPA 54:10.10.1]

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are observed. Horizontal furnaces shall be permitted to be installed in an attic, furred, or under-floor space, provided the required listings and furnace and duct clearances are observed.

Factory-built solidfuel-fired furnaces shall comply with UL 391 and shall be installed in accordance with the manufacturer’s installation

instructions.

Oil-fired central furnaces shall comply with UL 727 and shall be installed in accordance with the manufacturer’s installation instructions.

Commercial or industrial gas-fired heaters shall comply with UL 795 and shall be installed in accordance with the manufac turer’s installation instructions.

Electric central heating furnaces shall comply with UL 1995 or UL 60335-2-40 and shall be installed in accordance with the manufacturer’s

installation instructions.

MBtu/hr (2931 kW) or less shall be listed in accordance with ANSI Z83.8/CSA 2.6. [NFPA 54:10.9.1]

comply with the following clearance requirements:

(1) Listed duct furnaces shall be installed with clearances of not less than 6 inches (152 mm) between adjacent walls, ceilings, and floors of combustible material and the furnace draft hood. Furnaces listed for installation at lesser

clearances shall be installed in accordance with their list ings and the manufacturer’s installation instructions. In no case shall the clearance be such as to interfere with

combustion air and accessibility.

(2) Unlisted duct furnaces shall be installed with clearances to combustible material in accordance with the clear ances specified for unlisted furnaces and boilers in Table 904.3.2. Combustible floors under unlisted duct furnaces

shall be protected in an approved manner.

be installed in accordance with the manufacturer’s instruc tions. [NFPA 54:10.9.3]

naces shall have removable access panels on both the upstream and downstream sides of the furnace. [NFPA 54:10.9.4]

trols, combustion air inlet, and draft hoods for duct furnaces shall be located outside the ducts. The draft hood shall be

located in the same enclosure from which combustion air is

taken. [NFPA 54:10.9.5]

that supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air shall

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INSTALLATION OF SPECIFIC APPLIANCES

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comply with the following requirements:

(1) Listed floor furnaces shall be installed in accordance with their listing and the manufacturer’s installation instructions.

(2) Unlisted floor furnaces shall not be installed on combustible floors.

(3) Thermostats controlling floor furnaces shall not be located in a room or space that is capable of being separated from the room or space in which the register of the floor furnace is located. {NFPA 54:10.10.1}

Automatically operated floor furnaces shall be equipped with temperature limit controls. [NFPA 54:10.10.3]

circulating air shall be provided in accordance with Section 701.0. [NFPA 54:10.10.4]

(1) Floors. Floor furnaces shall not be installed in the floor of any doorway, stairway landing, aisle, or passageway of any enclosure, public or private, or in an exitway from any such room or space.

(2) Walls and Corners. The register of a floor furnace with a horizontal warm air outlet shall not be placed closer than 6 inches (152 mm) from the nearest wall. A distance of at least 18 inches (457 mm) from two adjoining sides of the floor furnace register to walls shall be provided to eliminate the necessity of occupants walking over the warm air discharge. The remaining sides shall be a minimum of 6 inches (152 mm) from a wall. Wall register models shall not be placed closer than 6 inches (152 mm) to a corner.

(3) Draperies. The furnace shall be placed so that a door, drapery, or similar object cannot be nearer than 12 inches (305 mm) to any portion of the register of the furnace.

[NFPA 54:10.10.5]

framed with doubled joists and with headers not lighter than the joists. [NFPA 54:10.10.6]

Means shall be provided to support the furnace when the floor register is removed. [NFPA 54:10.10.7]

shall have at least a 6 inch (152 mm) clearance from the general ground level. A reduced clearance to a minimum of 2 inches (51 mm) shall be permitted, provided the lower 6 inches (152 mm) portion of the floor furnace is sealed by the manufacturer to prevent entrance of water. Where these clearances are not present, the ground below and to the sides shall be excavated to form a “basin-like” pit under the furnace so that the required clearance is provided beneath the lowest portion of the furnace. A 12 inch (305 mm) clearance shall be provided on all sides except the control side, which shall have an 18 inch (457 mm) clearance. [NFPA 54:10.10.8]

installed shall be accessible by an opening in the foundation not less than 24 inches by 18 inches (610 mm by 457 mm) or

by a trapdoor not less than 24 inches by 24 inches (610 mm by 610 mm) in any cross-section thereof, and a passageway not less than 24 inches by 18 inches (610 mm by 457 mm) in any cross-section thereof. [NFPA 54:10.10.9]

inches (305 mm) in depth or water seepage is likely to collect, a watertight copper pan, concrete pit, or other suitable material shall be used, unless adequate drainage is provided or the appliance is sealed by the manufacturer to meet this condition. A copper pan shall be made of not less than 16 ounces per square foot (oz/ft [2] ) (4.9 kg/m [2] ) sheet copper. The pan shall be anchored in place so as to prevent floating, and the walls shall extend at least 4 inches (102 mm) above the ground level with at least a 6 inches (152 mm) clearance on all sides, except on the control side, which shall have at least an 18 inch (457 mm) clearance. [NFPA 54:10.10.10]

where necessary, against severe wind conditions. [NFPA 54:10.10.11]

be permitted to be installed in an upper floor, provided the furnace assembly projects below into a utility room, closet, garage, or similar nonhabitable space. In such installations, the floor furnace shall be enclosed completely (entirely separated from the nonhabitable space) with means for air intake to meet the provisions of Section 701.0, with access for servicing, minimum furnace clearances of 6 inches (152 mm) to all sides and bottom, and with the enclosure constructed of Portland cement plaster or metal lath or other noncombustible material. [NFPA 54:10.10.12]

the first or ground floors of buildings shall not be required to be enclosed unless the basements of these buildings have been converted to apartments or sleeping quarters, in which case the floor furnace shall be enclosed as specified for upper floor installations and shall project into a nonhabitable space.

[NFPA 54:10.10.13]

shall comply with UL 729 and installed in accordance with the manufacturer’s installation instructions.

Wall furnaces shall be listed in accordance with ANSI Z21.86/CSA 2.32. [NFPA 54:10.25.1]

dance with the manufacturer’s installation instructions. Wall

furnaces installed in or attached to combustible material shall be listed for such installation. [NFPA 54:10.25.2.1]

907.2.1 Vented Wall Furnaces. Vented wall furnaces connected to a Type B-W gas vent system listed only for a single story shall be installed only in single-story buildings or the top story of multistory buildings. Vented wall furnaces connected to a Type B-W gas vent system listed for installation in multistory buildings shall be permitted to be installed in single-story or multistory buildings. Type B-W gas vents shall be attached directly to a solid header plate that serves as a firestop at that point and that

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INSTALLATION OF SPECIFIC APPLIANCES

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circulating air shall be provided in accordance with Section 701.0. [NFPA 54:10.25.4]

shall comply with UL 730 and installed in accordance with the manufacturer’s installation instructions.

Clothes dryers shall be listed in accordance with ANSI Z21.5.1/CSA 7.1 for Type I clothes dryers or ANSI Z21.5.2/CSA 7.2 for Type II clothes dryers. [NFPA 54:10.4.1]

clothes dryers shall comply with UL 1240 and installed in accordance with the manufacturer’s installation instructions.

Residential and coin-operated electric clothes dryers shall comply with UL 2158 and installed in accordance with the manufacturer’s installation instructions.

Gas-fired clothes dryers shall comply with Section 908.3.1 through Section 908.3.3.

908.3.1 Clearance. The installation of clothes dryers shall comply with the following requirements:

(1) Listed Type 1 clothes dryers shall be installed with a clearance of not less than 6 inches (152 mm) from adjacent combustible material. Clothes dryers listed for installation at reduced clearances shall be

installed in accordance with their listing and the manufacturer’s installation instructions. Type 1 clothes dryers installed in closets shall be listed for such installation.

(2) Listed Type 2 clothes dryers shall be installed with clearances of not less than those shown on the mark ing plate and in the manufacturer’s instructions. Type 2 clothes dryers designed and marked, “For use only in noncombustible locations,” shall not be installed elsewhere.

(3) Unlisted clothes dryers shall be installed with clearances to combustible material of not less than 18

inches (457 mm). Combustible floors under unlisted clothes dryers shall be protected in an approved manner. {NFPA 54:10.4.2}

908.3.2 Exhausting to the Outdoors. Type 1 and Type 2 clothes dryers shall be exhausted to the outside air in accordance with Section 504.4. {NFPA 54:10.4.3}

908.3.3 Multiple-Family or Public Use. All clothes dryers installed for multiple-family or public use shall be installed as specified for a Type 2 clothes dryer under Section 504.4.3.1. [NFPA 54:10.4.7]

form to CSA Z21.8. [NFPA 54:10.5]

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shall be permitted to be an integral part of the vented wall furnace, as illustrated in Figure 907.2.1. The stud space in which the vented wall furnace is installed shall be ventilated at the first ceiling level by installation of the ceiling plate spacers furnished with the gas vent. Firestop spacers shall be installed at each subsequent ceiling or floor level penetrated by the vent. [NFPA 54:10.25.2.2]

907.2.2 Direct Vent Wall Furnaces. Direct vent wall

furnaces shall be installed with the combustion air intake

terminal outdoors. [NFPA 54:10.25.2.3]

907.2.3 Panels, Grilles, and Access Doors. Panels, grilles, and access doors that are required to be removed for normal servicing operations shall not be attached to the building. For additional information on the venting of wall furnaces, see Section 802.0. [NFPA 54:10.25.2.4]

For SI units: 1 inch = 25.4 mm

FIGURE 907.2.1

INSTALLATION OF TYPE B-W GAS VENTS FOR

VENTED WALL FURNACES

[NFPA 54: FIGURE 10.25.2.2]

cause a hazard to walls, floors, curtains, furniture, or doors. Wall furnaces installed between bathrooms and adjoining rooms shall not circulate air from bathrooms to other parts of the building. [NFPA 54:10.25.3]

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INSTALLATION OF SPECIFIC APPLIANCES

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and installed in accordance with the manufacturer’s installa tion instructions.

with UL 295 and installed in accordance with the manufac turer’s installation instructions.

Vented Fireplaces.

vented fireplaces shall be listed in accordance with ANSI Z21.60/CSA 2.26. [NFPA 54:10.6.1]

installation in vented fireplaces shall not be installed in bathrooms or bedrooms unless the bedroom or bathroom has the

required volume in accordance with Section 701.4. [NFPA 54:10.6.2] [OSHPD 1, 1R, 2, 4 & 5] A vented decorative appliance shall not be located in any hospital, skilled nursing facility, intermediate care facility, or correctional treatment

center.

in a vented fireplace shall be installed only in a vented fireplace having a working chimney flue and constructed of noncombustible materials. These appliances shall not be thermostatically controlled. [NFPA 54:10.6.3]

911.3.1 Listed Decorative Appliance. A listed decorative appliance for installation in a vented fireplace shall be installed in accordance with its listing and the manufacturer’s installation instructions. {NFPA 54:10.6.3.1}

911.3.2 Reserved

installed with a decorative appliance for installation in a vented fireplace. [NFPA 54:10.6.4]

accordance with ANSI Z21.50/CSA 2.22. [NFPA 54:10.7.1]

shall comply with the following requirements:

(1) [HCD 1 & HCD 2] Any newly installed gas fireplace shall be a direct-vent sealed-combustion type.

(2) Vented gas fireplaces shall be installed in accordance with their listing and the manufacturer’s installation instructions and where installed in or attached to com bustible material shall be specifically listed for such installation.

(3) Panels, grilles, and access doors that are required to be removed for normal servicing operations shall not be attached to the building.

(4) Direct vent gas fireplaces shall be installed with the vent air intake terminal in the outdoors and in accor dance with the manufacturer’s installation instructions.

[NFPA 54:10.7.3]

circulating air shall be provided in accordance with Section 701.0. [NFPA 54:10.7.4]

shall comply with UL 127 and installed in accordance with the manufacturer’s installation instructions. {NFPA 211:11.1.1} 913.1.1 Gasketed Fireplace Doors. A gasketed fireplace door shall not be installed on a factory-built fireplace, except where the fireplace system has been tested in accordance with UL 127.

with UL 737 and installed in accordance with the manufac turer’s installation instructions.

doors assemblies, combustion air vents, and termination caps shall comply with UL 907 and installed in accordance with the manufacturer’s installation instructions.

Air Heaters.

Direct gas-fired heating and forced ventilation appliances for commercial and industrial applications shall be listed in accordance with the following standards as applicable:

(1) ANSI Z83.4/CSA 3.7.

(2) ANSI Z83.18. [NFPA 54:10.8.1]

and forced ventilation appliances shall not serve any area containing sleeping quarters. Non-recirculating direct gas-fired heating and forced ventilation appliances shall not recirculate room air.

Recirculating direct gas-fired industrial air heaters shall not recirculate room air in buildings that contain flammable solids, liquids, or gases; explosive materials; or substances that can become toxic when exposed to flame or heat. [NFPA 54:10.8.2.1 – 10.8.2.3]

Direct gas-fired heating and forced ventilation appliances shall be installed in accordance with the manufacturer’s instructions. [NFPA 54:10.8.3.1]

914.3.1 Fresh Air Ventilation. Direct gas-fired heating and forced ventilation appliances shall be permitted to provide fresh air ventilation. [NFPA 54:10.8.3.2]

914.3.2 Access Required. Direct gas-fired heating and forced ventilation appliances shall be provided with access for removal of burners; for replacement of motors, controls, filters, and other working parts; and for adjustment and lubrication of parts requiring maintenance.

[NFPA 54:10.8.3.3]

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gas-fired heating and forced ventilation appliances shall be installed with a clearance from combustible materials of not less than that shown on the rating plate and the manufacturer’s instructions. [NFPA 54:10.8.4]

and forced ventilation appliances shall be in accordance with Section 914.5.1 through Section 914.5.3. [NFPA 54:10.8.5] 914.5.1 Non-Recirculating Systems. All air to the non-recirculating direct gas-fired heating and forced ventilation appliance shall be ducted directly from outdoors.

[NFPA 54:10.8.5.1] 914.5.2 Recirculating Systems. Ventilation air to the recirculating direct gas-fired heating and forced ventilation appliance shall be ducted directly from outdoors. Air in excess of the minimum ventilation air specified on the heater's rating plate shall be taken from the building, ducted directly from outdoors, or a combination of both.

[NFPA 54:10.8.5.2]

914.5.3 Dampers or Louvers. Where outdoor air dampers or closing louvers are used, they shall be verified to be in the open position prior to main burner operation. [NFPA 54:10.8.5.3]

Direct gas-fired heating and forced ventilation appliances with valve train components equipped with atmospheric vents, gas reliefs, or bleeds shall have their vent lines, gas reliefs, or bleeds lead to a safe point outdoors. Means shall be employed on these lines to prevent water from entering and to prevent blockage from insects and foreign matter. An atmospheric vent line shall not be required to be provided on a valve train component equipped with a listed vent limiter.

[NFPA 54:10.8.6]

include adequate provisions to permit the direct gas-fired heating and forced ventilation appliances to operate at their rated airflow without overpressurizing the space served by the heater by taking into account the structure’s designed infiltration rate, properly designed relief openings, or an interlocked powered exhaust system, or a combination of these methods. [NFPA 54:10.8.7] 914.7.1 Infiltration Rate. The structure’s designed infiltration rate and the size of relief opening(s) shall be determined by engineering methods. [NFPA 54:10.8.7.1] 914.7.2 Louver or Gravity Dampers. Louver or counterbalanced gravity damper relief openings shall be permitted. Where motorized dampers or closeable louvers are used, they shall be proved to be in their open position prior to main burner operation. [NFPA 54:10.8.7.2]

with at least four air changes prior to an ignition attempt.

[NFPA 54:10.8.8]

Room heaters shall be listed in accordance with Section 915.1.1 or Section 915.1.2. [NFPA 54:10.21.1]

915.1.1 Vented Room Heaters. Vented room heaters

shall be listed in accordance with ANSI Z21.86/CSA 2.32 or CSA/ANSI Z21.88/CSA 2.33. [NFPA 54:10.21.1.1]

915.1.2 Unvented Room Heaters. Unvented room

heaters shall be listed in accordance with CSA/ANSI

Z21.11.2. [NFPA 54:10.21.1.2]

comply with UL 2021.

shall comply with Section 915.3.1 through Section 915.3.4. 915.3.1 Prohibited Installations. Unless specifically permitted by the Authority Having Jurisdiction, unvented room heaters shall not be installed as primary heat sources. Unvented room heaters shall not be permitted in spaces that do not have the required volume of indoor air as defined in Section 701.4.

[HCD 1 & HCD 2] Unvented fuel-burning room heaters shall not be installed, used, maintained, or permitted to exist in a Group R Occupancy.

915.3.1.1 Unvented Room Heaters. Unvented

room heaters shall not be installed in bathrooms or

bedrooms.

Exceptions:

(1) Where approved, one listed wall-mounted unvented room heater equipped with an oxygen depletion safety shutoff system shall be permitted to be installed in a bathroom, provided that the input rating does not exceed 6000 Btu/h (1.76 kW) and combustion and ventilation air is provided as specified in Section 902.2.

(2) Where approved, one listed wall-mounted unvented room heater equipped with an oxygen depletion safety shutoff system shall be permitted to be installed in a bedroom, provided that the input rating does not exceed 10 000 Btu/h (3 kW) and combustion and ventilation air is provided as specified in Section 902.2. [NFPA 54:10.21.2]

(3) Portable oil fired unvented heating appliances used as supplemental heating in storage occupancies, utility occupancies, and in accordance with the fire code.

[HCD 1 & HCD 2] Unvented fuel-burning room heaters shall not be installed, used, maintained, or permitted to exist in a Group R Occupancy.

915.3.2 Installations in Institutions. Room heaters shall not be installed in the following occupancies:

(1) Residential board and care

(2) Health care [NFPA 54:10.21.3] 915.3.3 Clearance. A room heater shall be placed so as not to cause a hazard to walls, floors, curtains, furniture, doors where open, and to the free movements of persons within the room. Heaters designed and marked, “For use in noncombustible fireplace only,” shall not be installed elsewhere. Listed room heaters shall be installed in accordance with their listings and the manufacturer’s installation instructions. In no case shall the clearances be

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INSTALLATION OF SPECIFIC APPLIANCES

(1) A listed unit heater shall be installed with clearances from combustible material at the back and one side of not less than 6 inches (152 mm). Where the flue gases are vented horizontally, the 6 inch (152 mm) clearance shall be measured from the draft hood or

vent instead of the rear wall of the unit heater. A unit

heater listed for reduced clearances shall be installed in accordance with its listing and the manufacturer’s installation instructions.

(2) Floor-mounted-type unit heaters installed on combustible floors shall be listed for such installation.

(3) Combustible floors under unlisted floor-mounted unit heaters shall be protected in an approved man ner.

(4) Clearances for servicing shall be in accordance with the manufacturer’s instructions.

circulating air shall be provided in accordance with Section 701.0. [NFPA 54:10.24.4]

warm air duct system unless listed and marked for such installation. [NFPA 54:10.24.5]

craft Hangars. Unit heaters installed in garages for more than three motor vehicles or in aircraft hangars shall be installed in accordance with Section 303.11 and Section 303.12. [NFPA 54:10.24.6]

comply with UL 731 and installed in accordance with the manufacturer’s installation instructions.

shall be listed in accordance with ANSI Z83.11/CSA 1.8.

[NFPA 54:10.11.1]

food service appliances, such as ranges for hotels and restaurants, deep fat fryers, unit broilers, kettles, steam cookers, steam generators, and baking and roasting ovens, shall be installed not less than 6 inches (152 mm) from combustible material except that at least a 2 inch (51 mm) clearance shall be maintained between a draft hood and combustible material. Floor-mounted food service appliances listed for installation at lesser clearances shall be installed in accordance with its listing and the manufacturer’s installation instructions. Appliances designed and marked, “For use only in noncombustible locations,” shall not be installed elsewhere. [NFPA 54:10.11.2]

food service appliances that are listed specifically for installation on floors constructed of combustible material shall be permitted to be installed on combustible floors in accordance with its listing and the manufacturer’s installation instructions. [NFPA 54:10.11.3.1]

917.3.1 Not Listed for Mounting on Combustible Floors. Floor-mounted food service appliances that are not listed for installation on a combustible floor shall be

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such as to interfere with combustion air and accessibility. Unlisted room heaters shall be installed with clearances from combustible material not less than the following:

(1) Circulating type room heaters having an outer jacket surrounding the combustion chamber, arranged with openings at top and bottom so that air circulates between the inner and outer jacket, and without openings in the outer jacket to permit direct radiation, shall have clearance at sides and rear of not less than 12 inches (305 mm).

(2) Radiating type room heaters other than those of the circulating type described in Section 915.3.3(1) shall have clearance at sides and rear of not less than 18 inches (457 mm), except that heaters that make use of metal, asbestos, or ceramic material to direct radiation to the front of the heater shall have a clearance of 36 inches (914 mm) in front and, where constructed with a double back of metal or ceramic, shall be permitted to be installed with a clearance of 18 inches (457 mm) at sides and 12 inches (305 mm) at rear. Combustible floors under unlisted room heaters shall be protected in an approved manner.

915.3.4 Wall-Mounted Room Heaters. Wall mounted room heaters shall not be installed in or attached

to walls of combustible material unless listed for such installation. [NFPA 54:10.21.4]

room heaters shall comply with UL 1482.

Unit heaters shall be listed in accordance with ANSI Z83.8/CSA 2.6 and installed in accordance with the manufacturer’s installation instructions. [NFPA 54:10.24.1]

and adequately supported, with due consideration given to their weight and vibration characteristics. Hangers and brackets shall be of noncombustible material. [NFPA 54:10.24.2]

Suspended-type unit heaters shall comply with the following requirements:

(1) Unit heaters shall be installed with clearances from combustible material of not less than 18 inches (457 mm) at the sides, 12 inches (305 mm) at the bottom, and 6 inches (152 mm) above the top where the unit heater has an internal draft hood, or 1 inch (25.4 mm) above the top of the sloping side of a vertical draft hood. A unit heater listed for reduced clearances shall be installed in accordance with its listing and the manufacturer’s installation instructions.

(2) Clearances for servicing shall be in accordance with the manufacturer’s installation instructions. {NFPA 54:10.24.3}

916.3.1 Floor-Mounted-Type Unit Heaters. Floormounted-type unit heaters shall comply with the following requirements:

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INSTALLATION OF SPECIFIC APPLIANCES

permitted where protected in accordance with Table 303.10.1.

[NFPA 54:10.11.5]

casters shall be listed for such construction and shall be

installed in accordance with the manufacturer’s installation instructions for limiting the movement of the appliance to prevent strain on the connection. [NFPA 54:10.11.6]

appliances shall be installed level on a firm foundation.

[NFPA 54:10.11.7]

Means shall be provided to properly ventilate the space in which a food service appliance is installed to permit proper combustion of the gas. [NFPA 54:10.11.8]

be listed in accordance with ANSI Z83.11/CSA 1.8. [NFPA 54:10.12.1]

than 48 inches (1219 mm) shall be provided between the top of all food service hot plates and griddles and combustible material. [NFPA 54:10.12.2]

service counter appliances such as hot plates and griddles, food and dish warmers, and coffee brewers and urns, where installed on combustible surfaces, shall be set on their own bases or legs and shall be installed with a horizontal clearance of not less than 6 inches (152 mm) from combustible material, except that not less than a 2 inches (51 mm) clearance shall be maintained between a draft hood and combustible material. Food service counter appliances listed for installation at lesser clearances shall be installed in accordance with their listing and the manufacturer’s installation instructions.

Food service counter appliances, where installed on combustible surfaces, shall be installed with a minimum horizontal clearance of 6 inches (152 mm) from combustible material, except that at least a 2 inch (51 mm) clearance shall be maintained between a draft hood and combustible material. Food service counter appliances listed for installation at lesser clearances shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:10.12.3]

listed in accordance with CSA/ANSI Z21.1/CSA 1.1. [NFPA 54:10.13.1]

Electric household cooking appliances designed for permanent installations shall be installed in accordance with the manufacturer’s installation instructions. Household electric ranges shall comply with UL 858.

Gas-fired household cooking appliances shall comply with Section 919.4 though Section 919.6.

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installed in accordance with Section 917.4 or be installed in accordance with one of the following:

(1) Where the appliance is set on legs that provide not less than 18 inches (457 mm) open space under the base of the appliance or where it has no burners and no portion of any oven or broiler within 18 inches (457 mm) of the floor, it shall be permitted to be installed on a combustible floor without special floor protection, provided at least one sheet metal baffle is between the burner and the floor.

(2) Where the appliance is set on legs that provide not less than 8 inches (203 mm) open space under the base of the appliance, it shall be permitted to be installed on combustible floors, provided the floor under the appliance is protected with not less than 3 ⁄ 8 of an inch (9.5 mm) insulating millboard covered with sheet metal not less than 0.0195 of an inch (0.4953 mm) thick. The preceding specified floor protection shall extend not less than 6 inches (152 mm) beyond the appliance on all sides.

(3) Where the appliance is set on legs that provide not less than 4 inches (102 mm) under the base of the appliance, it shall be permitted to be installed on combustible floors, provided the floor under the appliance is protected with hollow masonry not less than 4 inches (102 mm) in thickness covered with sheet metal not less than 0.0195 of an inch (0.4953 mm) thick. Such masonry courses shall be laid with ends unsealed and joints matched in such a way as to provide for free circulation of air through the

masonry.

(4) Where the appliance does not have legs at least 4 inches (102 mm) high, it shall be permitted to be installed on combustible floors, provided the floor under the appliance is protected by two courses of 4 inch (102 mm) hollow clay tile, or equivalent, with courses laid at right angles and with ends unsealed and joints matched in such a way as to provide for free circulation of air through such masonry courses, and covered with steel plate not less than [3] ⁄ 16 of an inch (4.8 mm) in thickness. [NFPA 54:10.11.3.2]

Floorinstalled food service appliances that are designed and marked “For use only in noncombustible locations” shall be installed on floors of noncombustible construction with noncombustible flooring and surface finish and with no combustible material against the underside thereof, or on noncombustible slabs or arches having no combustible material against the underside thereof. Such construction shall in all cases extend not less than 12 inches (305 mm) beyond the appliance on all sides. [NFPA 54:10.11.4.1, 10.11.4.2]

Food service ranges shall be installed to provide clearance to combustible material of not less than 18 inches (457 mm) horizontally for a distance up to 2 feet (610 mm) above the surface of the cooking top where the combustible material is not completely shielded by high shelving, a warming closet, or other system. Reduced combustible material clearances are

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INSTALLATION OF SPECIFIC APPLIANCES

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installed in accordance with Section 919.4.1 and Section

919.4.2.

919.4.1 Clearances. Floor-mounted household cooking appliances, where installed on combustible floors, shall be set on their own bases or legs and shall not interfere with combustion air, accessibility for operation, and servicing. [NFPA 54:10.13.3]

919.4.2 Vertical Clearance Above Cooking Top. Household cooking appliances shall have a vertical clearance above the cooking top of not less than 30 inches (762 mm) to combustible material or metal cabinets. A minimum clearance of 24 inches (610 mm) shall be permitted where one of the following is installed:

(1) The underside of the combustible material or metal cabinet above the cooking top is protected with not less than [1] ⁄ 4 of an inch (6.4 mm) insulating millboard covered with sheet metal not less than 0.0122 of an inch (0.3099 mm) thick.

(2) A metal ventilating hood of sheet metal not less than 0.0122 of an inch (0.3099 mm) thick is installed above the cooking top with a clearance of not less than [1] ⁄ 4 of an inch (6.4 mm) between the hood and the underside of the combustible material or metal

cabinet, and the hood is not less than the width of the appliance and is centered over the appliance.

(3) A listed cooking appliance or microwave oven installed over a listed cooking appliance shall be in accordance with the terms of the upper appliance’s listing and the manufacturer’s installation instructions. {NFPA 54:10.13.3.1} Microwave ovens shall comply with UL 923.

dance with Section 919.5.1 and Section 919.5.2.

919.5.1 Installation. Listed built-in household cooking appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions. The installation shall not interfere with combustion air, accessibility for operation, and servicing. Unlisted builtin household cooking appliances shall not be installed in or adjacent to combustible material.

919.5.2 Vertical Clearance Above Cooking Top. Built-in top (or surface) cooking appliances shall have a vertical clearance above the cooking top of not less than 30 inches (762 mm) to combustible material or metal cabinets. A clearance of not less than 24 inches (610 mm) is permitted where one of the following is installed:

(1) The underside of the combustible material or metal cabinet above the cooking top is protected with not less than [1] ⁄ 4 of an inch (6.4 mm) insulating millboard covered with sheet metal not less than 0.0122 of an inch (0.3099 mm) thick.

(2) A metal ventilating hood of sheet metal not less than 0.0122 of an inch (0.3099 mm) thick is installed above the cooking top with a clearance of not less

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than [1] ⁄ 4 of an inch (6.4 mm) between the hood and the underside of the combustible material or metal

cabinet, and the hood not less than the width of the appliance and is centered over the appliance.

(3) A listed cooking appliance or microwave oven installed over a listed cooking appliance shall be in accordance with the terms of the upper appliance’s listing and the manufacturer’s installation instructions. Microwave ovens shall comply with UL 923.

installed so that the cooking top, broiler pan, or oven racks are level. [NFPA 54-2018:10.14.3]

Commercial electric ranges shall comply with UL 197 and installed in accordance with the manufacturer’s installation instructions.

Commercial wood-fired baking ovens (refractory type) shall comply with UL 2162 and installed in accordance with the manufacturer’s installation instructions.

Oil-burning ranges shall comply with UL 896 and installed in accordance with the manufacturer’s installation instructions.

accordance with ANSI Z83.11/CSA 1.8 or ANSI/CSA

Z21.1/CSA 1.1 and installed in accordance with the manu facturer’s installation instructions. [NFPA 54:10.17.1]

Domestic opentop broiler units shall be provided with a metal ventilating hood not less than 0.0122 of an inch (0.3099 mm) thick with a clearance of not less than [1] ⁄ 4 of an inch (6.4 mm) between the hood and the underside of combustible material or metal cabinets. A

clearance of at least 24 inches (610 mm) shall be maintained between the cooking top and the combustible material or metal cabinet, and the hood shall be at least as wide as the open-top broiler unit and centered over the unit. Domestic open-top broiler units incorporating an integral exhaust system and listed for use without a ventilating hood shall not be required to be provided with a ventilating hood if installed in accordance with Section 919.4.2(1). [NFPA 54:10.17.2]

units shall be provided with ventilation in accordance with Chapter 5, Part II. {NFPA 54:10.17.3}

listed in accordance with ANSI Z83.11/CSA 1.8, ANSI Z21.58/CSA 1.6, or ANSI Z21.89/CSA 1.18, and installed in accordance with the manufacturer’s installation instructions.

[NFPA 54:10.18]

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Listed illuminating appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions. {NFPA 54:10.14.1}

for unlisted illuminating appliances shall comply with the following:

(1) Unlisted enclosed illuminating appliances installed outdoors shall be installed with clearances in any direction from combustible material of not less than 12 inches (305 mm). [NFPA 54:10.14.2.1(1)]

(2) Unlisted enclosed illuminating appliances installed indoors shall be installed with clearances in any direction from combustible material of not less than 18 inches

(457 mm). [NFPA 54:10.14.2.1(2)]

923.2.1 Open-Flame Type. Clearance shall comply with the following:

(1) Unlisted open-flame illuminating appliances installed outdoors shall have clearances from com bustible material not less than that specified in Table 923.2.1. The distance from ground level to the base of the burner shall be a minimum of 7 feet (2134 mm) where installed within 2 feet (610 mm) of walkways. Lesser clearances shall be permitted to be used where acceptable to the Authority Having Jurisdiction.

(2) Unlisted open-flame illuminating appliances installed outdoors shall be equipped with a limiting orifice or other limiting devices that maintain a flame height consistent with the clearance from combustible material, as given in Table 923.2.1.

(3) Appliances designed for flame heights in excess of 30 inches (762 mm) shall be approved. Such appliances shall be equipped with a safety shutoff device or automatic ignition.

(4) Clearances to combustible material from unlisted open-flame illuminating appliances shall be approved. [NFPA 54:10.14.2.2]

TABLE 923.2.1

CLEARANCES FOR UNLISTED OUTDOOR

OPEN-FLAME ILLUMINATING APPLIANCES

[NFPA 54:TABLE 10.14.2.2]

designed for installation on a wall or ceiling shall be securely attached to substantial structures in such a manner that they are not dependent on the gas piping for support. [NFPA 54:10.14.3]

designed for installation on a post shall be securely and rigidly attached to a post. Posts shall be rigidly installed. The strength and rigidity of posts greater than 3 feet (914 mm) in height shall be at least equivalent to that of a 2 [1] ⁄ 2 inch (64 mm) diameter post constructed of 0.064 of an inch (1.626 mm) thick steel or a 1 inch (25.4 mm) Schedule 40 steel pipe. Posts 3 feet (914 mm) or less in height shall not be smaller than a 3 ⁄ 4 of an inch (19.1 mm) Schedule 40 steel pipe. Drain openings shall be provided near the base of posts where water collecting inside the posts is possible. [NFPA 54:10.14.4]

Where an appliance pressure regulator is not supplied with an illuminating appliance and the service line is not equipped with a service pressure regulator, an appliance pressure regulator shall be installed in the line serving one or more illuminating appliances. [NFPA 54:10.14.5]

Incinerators. Field constructed commercial-industrial incin erators shall be constructed and installed in accordance with

NFPA 82.

Factorybuilt commercial incinerators and crematories shall comply with UL 2790 and installed in accordance with the manufac turer’s installation instructions.

shall comply with UL 791 and installed in accordance with the manufacturer’s installation instructions.

of 400 000 Btu/hr (117 kW) or less shall be listed in accordance with ANSI Z83.19/CSA 2.35 or ANSI Z83.20/CSA 2.34. [NFPA 54:10.16.1]

fixed in position independent of gas and electric supply lines. Hangers and brackets shall be of noncombustible material. Heaters subject to vibration shall be provided with vibrationisolating hangers. [NFPA 54:10.16.2]

comply with the following clearance requirements:

(1) Listed heaters shall be installed with clearances from combustible material in accordance with their listing and the manufacturer’s installation instructions.

(2) Unlisted heaters shall be installed in accordance with clearances from combustible material acceptable to the Authority Having Jurisdiction.

(3) In locations used for the storage of combustible materials, signs shall be posted to specify the maximum per

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For SI units: 1 inch = 25.4 mm, 1 foot = 304.8 mm

• Measured from the nearest portion of the burner head.

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INSTALLATION OF SPECIFIC APPLIANCES

Refrigerators shall be provided with clearances for ventilation at the top and back in accordance with the manufacturer’s instructions. Where such instructions are

not available, at least 2 inches (51 mm) shall be provided between the back of the refrigerator and the wall at least 12 inches (305 mm) above the top. [NFPA 54:10.20.2]

with a Refrigerator. Where an accessory kit is used for conveying air for burner combustion or unit cooling to the refrigerator from areas outside the room in which it is located, or for conveying combustion products diluted with air containing waste heat from the refrigerator to areas outside the room in which it is located, the kit shall be installed in accordance with the refrigerator manufacturer’s instructions. [NFPA 54:10.20.3]

in accordance with its listing and the manufacturer’s installation instructions, provided that the clearance shall be such to afford ready accessibility for use, cleanout, and necessary servicing. {NFPA 54:10.23.1}

Listed gasfired toilets installed on combustible floors shall be listed for

such installation. [NFPA 54:10.23.2]

being contacted during casual use of the room in which the toilet is installed shall be protected or shielded to prevent such contact. [NFPA 54:10.23.3]

Housing. [Not adopted by HCD]

installed in manufactured housing after the initial sale shall be listed for installation in manufactured housing, or approved, and shall be installed in accordance with the requirements of this code and the manufacturer’s installation instructions.

Appliances installed in the living space of manufactured housing shall be in accordance with the requirements of Section 701.0. [NFPA 54:10.28]

used for ceramics that have a maximum interior volume of 20 cubic feet (0.57 m [3] ) and are used for hobby or noncommercial purposes.

with the manufacturer’s installation instructions and the provisions of this code.

with Section 306.0 and Section 902.4. Standing pilots shall not be used with gas-fired kilns.

used as part of, or in connection with, the installation of a kiln

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missible stacking height to maintain required clearances from the heater to the combustibles. {NFPA 54:10.16.3}

infrared heaters are used, natural or mechanical means shall be provided to supply and exhaust at least 4 ft [3] /min/1000 Btu/h (0.38 m [3] /min/kW) input of installed heaters. [NFPA 54:10.16.4.1]

925.4.1 Exhaust Openings. Exhaust openings for removing flue products shall be above the level of the heaters. [NFPA 54:10.16.4.2]

craft Hangars. Overhead heaters installed in garages for more than three motor vehicles or in aircraft hangars shall be listed and shall be installed in accordance with Section 303.11 and Section 303.12. [NFPA 54:10.16.5]

shall comply with UL 2021 and installed in accordance with the manufacturer’s installation instructions.

Pool heaters shall be listed in accordance with CSA/ANSI Z21.56/CSA 4.7. [NFPA 54:10.19.1]

so as to minimize accidental contact of hot surfaces by persons. [NFPA 54:10.19.2]

comply with the following requirements:

(1) The clearances shall not interfere with combustion air, draft hood or vent terminal clearance and relief, and accessibility for servicing.

(2) A pool heater shall be installed in accordance with its listing and the manufacturer’s installation instructions.

[NFPA 54:10.19.3]

Where a pool heater is provided with over-temperature protection only and is installed with any device in the discharge line of the heater that can restrict the flow of water from the heater to the pool (such as a check valve, shutoff valve, therapeutic pool valving, or flow nozzles), a pressure relief valve shall be installed either in the heater or between the heater and the restrictive device. [NFPA 54:10.19.4]

not provided as a part of the pool heater, a bypass line and valve shall be installed between the inlet and outlet piping for use in adjusting the flow of water through the heater. [NFPA 54:10.19.5]

shall be installed with the venting means supplied by the manufacturer and in accordance with the manufacturer’s installation instructions. [NFPA 54:10.19.6]

Refrigerators shall be listed in accordance with CSA/ANSI Z21.19/CSA 1.4. [NFPA 54:10.20.1]

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212 2025 CALIFORNIA MECHANICAL CODE

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

INSTALLATION OF SPECIFIC APPLIANCES

enclosed by more than two vertical wall surfaces, a hood and gravity ventilation duct shall be installed in accordance with Section 930.5.2, Section 930.5.3, and Section 603.13.6.

flame decorative appliances shall be installed in accordance with Section 931.1.1 and Section 931.1.2. [NFPA 54:10.30] 931.1.1 Application. Outdoor open flame decorative appliances shall be listed in accordance with ANSI Z21.97/CSA 2.41 and shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:10.30.1] 931.1.2 Connection to the Piping System. The connection to the gas piping system shall be in accordance with Section 1312.1(1), Section 1312.1(2), Section 1312.1(4), or Section 1312.1(5). [NFPA 54:10.30.2]

ducts and fire dampers that are a portion of an evaporative cooling system, shall be in accordance with Section 932.2 through Section 932.4.3. Evaporative cooling systems shall be provided with outside air as specified for cooling systems in Section 403.0.

installed so as to minimize the probability of damage from an external source.

coolers shall be accessible for inspection, service, and replacement without removing permanent construction.

building structure shall be installed on a level base and shall be secured directly or indirectly to the building structure, to prevent displacement of the cooler. 932.4.1 Modifications to the Supporting Struc- ture. Modifications made to the supporting framework of buildings as a result of the installation shall be in accordance with the requirements of the building code. Openings in exterior walls shall be flashed in an approved manner in accordance with the requirements of the building code. 932.4.2 On the Ground. An evaporative cooler supported directly by the ground shall be isolated from the ground by a level concrete slab extending not less than 3 inches (76 mm) above the adjoining ground level. 932.4.3 On a Platform. An evaporative cooler supported on an aboveground platform shall be elevated not less than 6 inches (152 mm) above adjoining ground level.

Factory-built commercial refrigerators and freezers shall comply with UL 471 or UL 60335-2-89 and shall be installed in accor dance with the manufacturer’s installation instructions.

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shall be in accordance with the requirements in NFPA 70. Electric kilns shall be listed and labeled in accordance with

UL 499.

requirements specified in this section, interior installations shall comply with the requirements of Section 603.13.6 and Section 930.5.1 through Section 930.5.4.

930.5.1 Kiln Clearances. The sides and tops of kilns shall be located not less than 18 inches (457 mm) from a noncombustible wall surface and 3 feet (914 mm) from a combustible wall surface. Kilns shall be installed on

noncombustible flooring consisting of not less than 2 inches (51 mm) of solid masonry or concrete extending not less than 12 inches (305 mm) beyond the base or supporting members of the kiln.

Exception: These clearances shall be permitted to be reduced, provided the kiln is installed in accordance with its listing.

In no case shall the clearance on the gas or electrical control side of a kiln be reduced to less than 30 inches

(762 mm).

930.5.2 Hoods. A canopy-type hood shall be installed directly above each kiln. The face opening area of the hood shall be equal to or greater than the top horizontal surface area of the kiln. The hood shall be constructed of

not less than 0.024 of an inch (0.61 mm) (No. 24 gauge) galvanized steel or equivalent and be supported at a height of between 12 inches (305 mm) and 30 inches (762 mm) above the kiln by noncombustible supports.

Exception: Electric kilns installed with listed exhaust blowers shall be permitted to be used where marked as being suitable for the kiln and installed in accordance with the manufacturer’s installation instructions.

930.5.3 Gravity Ventilation Ducts. Each hood shall be connected to a gravity ventilation duct extending in a vertical direction to outside the building. This duct shall be of the same construction as the hood and shall have a

minimum cross-sectional area of not less than one-fif teenth of the face opening area of the hood. The duct shall terminate not less than 12 inches (305 mm) above a portion of a building within 4 feet (1219 mm) and terminate not less than 4 feet (1219 mm) from an openable window or other opening into the building or adjacent property line. The duct opening to the outside shall be shielded, without reduction of duct area, to prevent entrance of rain into the duct. The duct shall be supported at each section by noncombustible supports.

930.5.4 Makeup Air. Provisions shall be made for air to enter the room in which a kiln is installed at a rate not

less than the air being removed through the kiln hood.

minimum clearances as specified in Section 930.5.1. Wherever a kiln is located under a roofed area and is partially

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

INSTALLATION OF SPECIFIC APPLIANCES

refrigerators, freezers, refrigerated warehouses, and walk-in coolers shall comply with UL 412 or UL 60335-2-89 and shall be installed in accordance with the manufacturer’s

installation instructions.

tems. Self-contained mechanical refrigeration systems for use in walk-in coolers shall comply with UL 427 or UL 60335-2-89 and shall be installed in accordance with the man ufacturer’s installation instructions.

shall be installed in accordance with the manufacturer’s

installation instructions and Section 310.2 for condensate

control.

Electrostatic air cleaners shall comply with UL 867 and installed in accordance with the manufacturer’s installation instructions.

High-efficiency particulate air filter units for use in industrial and laboratory exhaust and ventilation systems shall be installed in accordance with the manufacturer’s installation

instructions.

in accordance with NFPA 2.

Systems.

(CNG) fueling (dispensing) systems shall be in accordance with NFPA 52. Residential CNG fueling appliances shall be listed in accordance with ANSI/CSA NGV 5.1 and installed in accordance to the appliance manufacturer’s installation instructions. Non-residential CNG fueling appliances shall be listed in accordance with ANSI/CSA NGV 5.2 and installed in accordance with the appliance manufacturer’s installation instructions. [NFPA 54:10.27]

Dehumidifiers shall comply with UL 603352-40, and be installed in accordance with the manufacturer’s installation instructions.

Sauna heaters shall comply with UL 875 and shall be installed in accordance with the manufacturer’s installation instructions.

214 2025 CALIFORNIA MECHANICAL CODE

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

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE