UL 731-2009 pdf download – Oil-Fired Unit Heaters.
2.1 1 BURNER, MECHANICAL-ATOMIZING TYPE – A power-operated burner which prepares and delivers the oil and all or part of the air by mechanical process in controllable quantities for combustion. Some examples are air atomizing, high and low pressure atomizing, horizontal rotary, vertical rotary atomizing, and vertical rotary wall-flame burners. 2.1 2 BURNER, MECHANICAL DRAFT TYPE – A burner which includes a power-driven fan, blower, or other mechanism as the principal means for supplying air for combustion. 2.1 3 BURNER, NATURAL DRAFT TYPE – A burner which depends principally upon the natural draft created in the flue to induce into the burner the air required for combustion. 2.1 4 BURNER, VAPORIZING TYPE – A burner consisting of an oil-vaporizing bowl or other receptacle to which liquid fuel may be fed in controllable quantities. The heat of combustion is used to vaporize the fuel, with provision for admitting air and mixing it with the oil vapor in combustible proportions. 2.1 5 CASING – An enclosure forming the outside of the appliance, no parts of which are likely to be subjected to intense heat. 2.1 6 CENTRAL HEATING APPLIANCE – A stationary indirect-fired vented appliance comprising the following classes: boilers, central furnaces, floor furnaces, and recessed heaters. A floor-mounted unit heater to be connected to a duct system is classified also as a central heating appliance. 2.1 7 CHIMNEY CONNECTOR – The pipe which connects a solid or liquid fuel burning appliance to a chimney. 2.1 8 COMBUSTIBLE MATERIAL – Combustible material as pertaining to materials adjacent to or in contact with heat-producing appliances, chimney connectors, vent connectors, and warm air ducts means material made of or surfaced with wood, compressed paper, plant fibers, or other material that will ignite and burn. Such material shall be considered as combustible even though flameproofed, fire retardant treated, or plastered.
2.1 9 COMBUSTION – As used herein, the rapid oxidation of fuel accompanied by the production of heat, or heat and light. Complete combustion of a fuel is possible only in the presence of an adequate supply of oxygen. 2.20 COMBUSTION CHAMBER – The portion of an appliance within which combustion occurs. 2.21 COMBUSTION (FLAME) SAFEGUARD – A safety combustion control. 2.22 CONSTANT-LEVEL VALVE – A device for maintaining within a reservoir a constant level of fuel for delivery to the burner. 2.23 CONTROL – A device designed to regulate the fuel, air, water, or electrical supply to the controlled equipment. It may be automatic, semiautomatic, or manual.