HVAC Gas Heat certification exam questions and answers

A gas furnace is to be installed in a garage. The national standards require that the burners and ignition sources must be located ______ above the floor - ans-18 inches A good description of how a bi-metal fan switch operates the blower motor on a gas furnace is - ans-Temperature on- temperature off Redundant gas valves used on gas furnaces have - ans-Dual gas shut off seats Burning one cubic foot of liquefied petroleum gas completely will produce approximately ______ BTUs - ans- LP gas has a specific gravity of - ans-1.5 - 2.0 What is the purpose of a spoiler screw located on a burner, or adjustable-shutters? - ans-Mix primary air and gas Furnace limit switches are wired in series with the - ans-Gas valve A technician is using an extension ladder to work on roof top unit. The top of the ladder should extend _____ beyond the support point - ans-3 feet