UL 307B

Please note: All interim revisions for this edition available at time of your purchase will be included.

Gas-Burning Heating Appliances for Manufactured Homes and Recreational Vehicles

UL 307B

1 Scope

1.1 These requirements apply to the following gas fuel-burning heating appliances:

a) Direct-vent system appliances for manufactured homes and recreational vehicles; and

b) Vented appliances for manufactured homes other than the direct-vent system type that provide for separation of the combustion system from the atmosphere of the manufactured home by an installation method.

1.2 Requirements for the installation and use of heating appliances in manufactured homes and recreational vehicles are included in:

a) The Department of Housing and Urban Development Manufactured Home Construction and Safety Standards, Chapter II of 24 CFR, Part 3280-1994; and

b) The Standard for Recreational Vehicles, NFPA 501C-1993.

1.3 An appliance designed to burn either oil or gas, and a gas appliance designed to be converted to burn oil by the installation of an optional factory-furnished burner, shall also comply with the requirements in the Standard for Liquid Fuel-Burning Heating Appliances for Manufactured Homes and Recreational Vehicles, UL 307A.

1.4 A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this Standard, and that involve a risk of fire, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the acceptable level of safety as originally anticipated by the intent of this Standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this Standard cannot be judged to comply with this Standard. Where considered appropriate, revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this Standard.