HVAC GAS HEAT EXAM | 2026 UPDATE | 100
QUESTIONS AND ANSWERS | WITH COMPLETE
SOLUTION
To test for an obstructed flue pipe on an induced draft furnace , a technician
should use ; Answer - a 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 ; Answer - 18
inches
3 . Redundant gas valves used on gas furnaces have ; Answer - B. no manual
gas shut off .
Burning one cubic foot of liquified petroleum ( LP ) gas completely will produce
approximately ; Answer - D. 2,000-2,500 Btu .
Liquified petroleum ( LP ) gas has a specific gravity of ; Answer - C. 1.5-2.0 .
What is the purpose of using an adjustable shutter on older burners ? Answer -
Mix primary air and gas
, The primary function of the limit switch is to de - energize the ; Answer - C. 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 ; Answer - C. 3 feet .
A technician determines that a natural gas furnace has a defective heat
exchanger , The technician should ; Answer - Inform 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 ; Answer - 3.5 inches WC
The National Fuel Gas Code classifies a vent system for a condensing furnace as
; Answer - D. Category IV
The minimum distance Type - B vent pipe must be kept from combustible
materials is ; Answer - D. one inch .
Typical condensing furnaces have an efficiency rating of at least ; Answer - D.
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 down .
The reason heating thermostats have anticipators or cycle rate adjustment is to
Answer - reduce temperature swing .
QUESTIONS AND ANSWERS | WITH COMPLETE
SOLUTION
To test for an obstructed flue pipe on an induced draft furnace , a technician
should use ; Answer - a 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 ; Answer - 18
inches
3 . Redundant gas valves used on gas furnaces have ; Answer - B. no manual
gas shut off .
Burning one cubic foot of liquified petroleum ( LP ) gas completely will produce
approximately ; Answer - D. 2,000-2,500 Btu .
Liquified petroleum ( LP ) gas has a specific gravity of ; Answer - C. 1.5-2.0 .
What is the purpose of using an adjustable shutter on older burners ? Answer -
Mix primary air and gas
, The primary function of the limit switch is to de - energize the ; Answer - C. 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 ; Answer - C. 3 feet .
A technician determines that a natural gas furnace has a defective heat
exchanger , The technician should ; Answer - Inform 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 ; Answer - 3.5 inches WC
The National Fuel Gas Code classifies a vent system for a condensing furnace as
; Answer - D. Category IV
The minimum distance Type - B vent pipe must be kept from combustible
materials is ; Answer - D. one inch .
Typical condensing furnaces have an efficiency rating of at least ; Answer - D.
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 down .
The reason heating thermostats have anticipators or cycle rate adjustment is to
Answer - reduce temperature swing .
