HVAC Gas Heat Certification Exam With All Correct &
100% Verified Answers |Latest Update|Already Graded
A+
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 ✔Correct Answer-18 inches
A good description of how a bi-metal fan switch operates the blower motor on a gas furnace is
✔Correct Answer-Temperature on- temperature off
Redundant gas valves used on gas furnaces have ✔Correct Answer-Dual gas shut off seats
Burning one cubic foot of liquefied petroleum gas completely will produce approximately ______
BTUs ✔Correct Answer-2000 - 2500
LP gas has a specific gravity of ✔Correct Answer-1.5 - 2.0
What is the purpose of a spoiler screw located on a burner, or adjustable-shutters? ✔Correct
Answer-Mix primary air and gas
Furnace limit switches are wired in series with the ✔Correct 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 ✔Correct Answer-3 feet
A technician determines that a natural gas furnace has a defective heat exchanger. The technician
should ✔Correct Answer-Inform the homeowner and turn the gas off
A natural gas furnace usually requires _____ gas pressure at the manifold and burners ✔Correct
Answer-3.5 in. W.C.
The vent system for a condensing furnace is classified as ____ by the National Field Gas Code.
✔Correct Answer-Category IV
Type B vent pipe must be kept at least _____ from combustible materials ✔Correct Answer-One
inch
Typical condensing furnaces have an AFUE rating of at least ✔Correct 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 ✔Correct Answer-
Point it down
The reason heating thermostat have anticipated is to ✔Correct Answer-Reduce lag
The typical flue gas temperature of a Category III furnace is ✔Correct Answer-280°F - 300°F
Natural gas primary consists of ✔Correct Answer-Methane
, Burning one cubic foot of natural gas will produce approximately _____ BTU's ✔Correct 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 ✔Correct Answer-Increase fan
speed
A BTU is the amount of heat required to raise the temperature of one pound of water ✔Correct
Answer-One degree Fahrenheit
Natural gas piping must be sized to prevent excessive pressure drops. The maximum pressure drop
allowance is approximately ✔Correct Answer-.5 in. W.C.
Gas piping must be installed with a pitch of ✔Correct Answer-1/4" per 15' run
Pipe joint compound should be applied to ✔Correct Answer-Male threads completely
A technician is installing a copper elbow on LP gas line; what should be used ✔Correct Answer-
95/5 solder
To burn one cubic foot of Natural Gas completely, at least _____ of combustion air must be available
✔Correct Answer-15 cu ft.
The ignition temperature of Natural Gas is ✔Correct Answer-1100°F - 1200°F
Air that is mixes with Natural Gas in the burner is called ✔Correct Answer-Primary air
What is the volume of flue gas produced from a 60,000 BTU/h Category I fan assisted Natural Gas
furnace operating with 50% excess air? ✔Correct Answer-600 cu ft.
The purpose of a flue baffle is to ✔Correct Answer-Increase heat exchange
The LP gas pressure supplied to the appliance gas valve should be ✔Correct Answer-11 - 13 in.
W.C.
An installed gas furnace should have a minimum of ✔Correct Answer-12
Which conditions listed below would cause the temperature limit safety switch to shut off the burner
✔Correct Answer-Fan motor failure
The cut off plate is a component of the ✔Correct Answer-Blower housing
A "spud" or burner orifice ✔Correct Answer-Meters gas to the burner
A good thermocouple should read approximately ____ on a D.C. meter ✔Correct Answer-30
millivolta
Liquefied petroleum, (LP) gases are ✔Correct Answer-Propane and butane
100% Verified Answers |Latest Update|Already Graded
A+
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 ✔Correct Answer-18 inches
A good description of how a bi-metal fan switch operates the blower motor on a gas furnace is
✔Correct Answer-Temperature on- temperature off
Redundant gas valves used on gas furnaces have ✔Correct Answer-Dual gas shut off seats
Burning one cubic foot of liquefied petroleum gas completely will produce approximately ______
BTUs ✔Correct Answer-2000 - 2500
LP gas has a specific gravity of ✔Correct Answer-1.5 - 2.0
What is the purpose of a spoiler screw located on a burner, or adjustable-shutters? ✔Correct
Answer-Mix primary air and gas
Furnace limit switches are wired in series with the ✔Correct 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 ✔Correct Answer-3 feet
A technician determines that a natural gas furnace has a defective heat exchanger. The technician
should ✔Correct Answer-Inform the homeowner and turn the gas off
A natural gas furnace usually requires _____ gas pressure at the manifold and burners ✔Correct
Answer-3.5 in. W.C.
The vent system for a condensing furnace is classified as ____ by the National Field Gas Code.
✔Correct Answer-Category IV
Type B vent pipe must be kept at least _____ from combustible materials ✔Correct Answer-One
inch
Typical condensing furnaces have an AFUE rating of at least ✔Correct 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 ✔Correct Answer-
Point it down
The reason heating thermostat have anticipated is to ✔Correct Answer-Reduce lag
The typical flue gas temperature of a Category III furnace is ✔Correct Answer-280°F - 300°F
Natural gas primary consists of ✔Correct Answer-Methane
, Burning one cubic foot of natural gas will produce approximately _____ BTU's ✔Correct 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 ✔Correct Answer-Increase fan
speed
A BTU is the amount of heat required to raise the temperature of one pound of water ✔Correct
Answer-One degree Fahrenheit
Natural gas piping must be sized to prevent excessive pressure drops. The maximum pressure drop
allowance is approximately ✔Correct Answer-.5 in. W.C.
Gas piping must be installed with a pitch of ✔Correct Answer-1/4" per 15' run
Pipe joint compound should be applied to ✔Correct Answer-Male threads completely
A technician is installing a copper elbow on LP gas line; what should be used ✔Correct Answer-
95/5 solder
To burn one cubic foot of Natural Gas completely, at least _____ of combustion air must be available
✔Correct Answer-15 cu ft.
The ignition temperature of Natural Gas is ✔Correct Answer-1100°F - 1200°F
Air that is mixes with Natural Gas in the burner is called ✔Correct Answer-Primary air
What is the volume of flue gas produced from a 60,000 BTU/h Category I fan assisted Natural Gas
furnace operating with 50% excess air? ✔Correct Answer-600 cu ft.
The purpose of a flue baffle is to ✔Correct Answer-Increase heat exchange
The LP gas pressure supplied to the appliance gas valve should be ✔Correct Answer-11 - 13 in.
W.C.
An installed gas furnace should have a minimum of ✔Correct Answer-12
Which conditions listed below would cause the temperature limit safety switch to shut off the burner
✔Correct Answer-Fan motor failure
The cut off plate is a component of the ✔Correct Answer-Blower housing
A "spud" or burner orifice ✔Correct Answer-Meters gas to the burner
A good thermocouple should read approximately ____ on a D.C. meter ✔Correct Answer-30
millivolta
Liquefied petroleum, (LP) gases are ✔Correct Answer-Propane and butane
