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 - (answer)18 inches
A good description of how a bi-metal fan switch operates the blower motor on a gas
furnace is - (answer)Temperature on- temperature off
Redundant gas valves used on gas furnaces have - (answer)Dual gas shut off seats
Burning one cubic foot of liquefied petroleum gas completely will produce
approximately ______ BTUs - (answer)2000 - 2500
LP gas has a specific gravity of - (answer)1.5 - 2.0
What is the purpose of a spoiler screw located on a burner, or adjustable-shutters? -
(answer)Mix primary air and gas
Furnace limit switches are wired in series with the - (answer)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 - (answer)3 feet
A technician determines that a natural gas furnace has a defective heat exchanger. The
technician should - (answer)Inform the homeowner and turn the gas off
A natural gas furnace usually requires _____ gas pressure at the manifold and burners -
(answer)3.5 in. W.C.
, HVAC GAS HEAT CERTIFICATION EXAM 2025 QUESTIONS WITH COMPLETE SOLUTIONS!!
The vent system for a condensing furnace is classified as ____ by the National Field Gas
Code. - (answer)Category IV
Type B vent pipe must be kept at least _____ from combustible materials - (answer)One
inch
Typical condensing furnaces have an AFUE rating of at least - (answer)90%
You have installed a Category IV two-pipe vent system that terminates through the roof
of the residence. The elbow for the combustion air intake, above the roof, should -
(answer)Point it down
The reason heating thermostat have anticipated is to - (answer)Reduce lag
The typical flue gas temperature of a Category III furnace is - (answer)280°F - 300°F
Natural gas primary consists of - (answer)Methane
Burning one cubic foot of natural gas will produce approximately _____ BTU's -
(answer)900~1,100
A furnace nameplate specifies a temperature rise of 40 to 70 degrees. Temperature
measurements indicate a rise of 80 degrees. The most appropriate action is to -
(answer)Increase fan speed