HVAC Gas Heat Exams (Latest 2024/ 2025 Updates
BUNDLE PACKAGE WITH COMPLETE SOLUTIONS) 100%
Correct Questions and Verified Answers | Grade A
To test for an obstructed flue pipe on an induced draft furnace , a technician should
use ; - ANSWERa manometer to test the negative pressure generated by the induced
draft motor
A gas furnace is to be installed in a garage . National standards require that the
burners and ignition sources must be located above the floor ; - ANSWER18 inches
3 . Redundant gas valves used on gas furnaces have ; - ANSWERB. no manual gas
shut off .
Burning one cubic foot of liquified petroleum ( LP ) gas completely will produce
approximately ; - ANSWERD. 2,000-2,500 Btu .
Liquified petroleum ( LP ) gas has a specific gravity of ; - ANSWERC. 1.5-2.0 .
What is the purpose of using an adjustable shutter on older burners ? - ANSWERMix
primary air and gas
The primary function of the limit switch is to de - energize the ; - ANSWERC. gas valve
if the furnace overheats .
A technician is using an extension ladder to work on a roof top unit . The top of the
ladder should extend beyond the support point by ; - ANSWERC. 3 feet .
A technician determines that a natural gas furnace has a defective heat exchanger ,
The technician should ; - ANSWERInform the homeowner and turn off the gas supply
to the furnace
The gas pressure usually required at the manifold and burners in a natural gas
furnace is ; - ANSWER3.5 inches WC
The National Fuel Gas Code classifies a vent system for a condensing furnace as ; -
ANSWERD. Category IV
The minimum distance Type - B vent pipe must be kept from combustible materials
is ; - ANSWERD. one inch .
Typical condensing furnaces have an efficiency rating of at least ; - ANSWERD. 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 ; - ANSWERpoint down .
, The reason heating thermostats have anticipators or cycle rate adjustment is to -
ANSWERreduce temperature swing .
Higher system efficiency is achieved in a category IV condensing furnace when the
water vapor in the flue gas condenses and releases ; - ANSWERdioxide latent heat .
Natural gas consists primarily of ; - ANSWERB. methane .
Burning one cubic foot of natural gas will produce approximately ; . - ANSWER900-
1,100 Btu .
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 ; -
ANSWERB. increase fan speed .
A Btu is the amount of heat required to raise the temperature of one pound of water
; - ANSWERone - degree Fahrenheit .
Pressure drop in a natural gas piping system primarily occurs due to ; -
ANSWERfriction or resistance caused by the pipe and fittings installed in the piping
system
Gas piping must be installed with a pitch of ; - ANSWER1/4 inch per 15 - foot run .
Pipe joint compound should be applied to ; - ANSWERmale threads , less two end
threads .
When a lockout / tagout is used during the service of a system ; - ANSWERthere
should be only one key , in possession of the technician performing the work .
How much combustion air is required to burn and properly vent one cubic foot of
natural gas ? - ANSWER10 cu ft .
The ignition temperature of natural gas is : - ANSWERD. 1100 F - 1200 ° F .
Air that is mixed with natural gas in the burner is called ; - ANSWERD. primary air .
What volume of flue gas is produced by a 60,000 Btu / h Category 1 , fan - assisted
natural gas furnace operating with 50 % excess air ? - ANSWERC. 780 cu ft .
The purpose of a flue baffle is to ; - ANSWERB. increase heat exchange .
The typical manifold pressure for a liquified petroleum ( LP ) gas appliance should
be ; - ANSWERD. 10-11 inches WC .
BUNDLE PACKAGE WITH COMPLETE SOLUTIONS) 100%
Correct Questions and Verified Answers | Grade A
To test for an obstructed flue pipe on an induced draft furnace , a technician should
use ; - ANSWERa manometer to test the negative pressure generated by the induced
draft motor
A gas furnace is to be installed in a garage . National standards require that the
burners and ignition sources must be located above the floor ; - ANSWER18 inches
3 . Redundant gas valves used on gas furnaces have ; - ANSWERB. no manual gas
shut off .
Burning one cubic foot of liquified petroleum ( LP ) gas completely will produce
approximately ; - ANSWERD. 2,000-2,500 Btu .
Liquified petroleum ( LP ) gas has a specific gravity of ; - ANSWERC. 1.5-2.0 .
What is the purpose of using an adjustable shutter on older burners ? - ANSWERMix
primary air and gas
The primary function of the limit switch is to de - energize the ; - ANSWERC. gas valve
if the furnace overheats .
A technician is using an extension ladder to work on a roof top unit . The top of the
ladder should extend beyond the support point by ; - ANSWERC. 3 feet .
A technician determines that a natural gas furnace has a defective heat exchanger ,
The technician should ; - ANSWERInform the homeowner and turn off the gas supply
to the furnace
The gas pressure usually required at the manifold and burners in a natural gas
furnace is ; - ANSWER3.5 inches WC
The National Fuel Gas Code classifies a vent system for a condensing furnace as ; -
ANSWERD. Category IV
The minimum distance Type - B vent pipe must be kept from combustible materials
is ; - ANSWERD. one inch .
Typical condensing furnaces have an efficiency rating of at least ; - ANSWERD. 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 ; - ANSWERpoint down .
, The reason heating thermostats have anticipators or cycle rate adjustment is to -
ANSWERreduce temperature swing .
Higher system efficiency is achieved in a category IV condensing furnace when the
water vapor in the flue gas condenses and releases ; - ANSWERdioxide latent heat .
Natural gas consists primarily of ; - ANSWERB. methane .
Burning one cubic foot of natural gas will produce approximately ; . - ANSWER900-
1,100 Btu .
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 ; -
ANSWERB. increase fan speed .
A Btu is the amount of heat required to raise the temperature of one pound of water
; - ANSWERone - degree Fahrenheit .
Pressure drop in a natural gas piping system primarily occurs due to ; -
ANSWERfriction or resistance caused by the pipe and fittings installed in the piping
system
Gas piping must be installed with a pitch of ; - ANSWER1/4 inch per 15 - foot run .
Pipe joint compound should be applied to ; - ANSWERmale threads , less two end
threads .
When a lockout / tagout is used during the service of a system ; - ANSWERthere
should be only one key , in possession of the technician performing the work .
How much combustion air is required to burn and properly vent one cubic foot of
natural gas ? - ANSWER10 cu ft .
The ignition temperature of natural gas is : - ANSWERD. 1100 F - 1200 ° F .
Air that is mixed with natural gas in the burner is called ; - ANSWERD. primary air .
What volume of flue gas is produced by a 60,000 Btu / h Category 1 , fan - assisted
natural gas furnace operating with 50 % excess air ? - ANSWERC. 780 cu ft .
The purpose of a flue baffle is to ; - ANSWERB. increase heat exchange .
The typical manifold pressure for a liquified petroleum ( LP ) gas appliance should
be ; - ANSWERD. 10-11 inches WC .
