NATE Gas Heating Exam Questions and
Answers 2026/2027 With 100%
Complete Solutions.
A crack in a heat exchanger can:
A: Allow combustion gases to mix with the space air
B: Prevent the heat from effectively transferring to the air
C: Cause the high-limit control to shut the furnace down
D: Cause the furnace to catch on fire - CORRECT ANSWER -A: Allow combustion
gases to mix with the space air
Gas valves operate on what voltage?
A: 12 volts
B: 24 volts
,C: 120 volts
D: 230 volts - CORRECT ANSWER -B: 24 volts
Mid-efficiency furnaces operate with flue gas temperatures between:
A: 275 and 360 degrees
B: 200 and 500 degrees
C: 100 and 275 degrees
D: 80 and 100 degrees - CORRECT ANSWER -A: 275 and 360 degrees
High-efficiency furnaces operate with flue gas temperatures between:
A: 275 and 360 degrees
B: 200 and 500 degrees
C: 100 and 275 degrees
, D: 80 and 100 degrees - CORRECT ANSWER -C: 100 and 275 degrees
"B" vent is:
A: Hard, inflexible white plastic vent tubing able to withstand temperatures up to
325 degrees F
B: Hard, inflexible white plastic vent tubing able to withstand temperatures up to
400 degrees F
C: Single wall sheet metal vent pipe
D: Double wall sheet metal vent pipe - CORRECT ANSWER -D: Double wall sheet
metal vent pipe
Latent heat is:
A: Heat that causes a change in temperature with no change in state
B: Heat that causes a change in state with no change in temperature
Answers 2026/2027 With 100%
Complete Solutions.
A crack in a heat exchanger can:
A: Allow combustion gases to mix with the space air
B: Prevent the heat from effectively transferring to the air
C: Cause the high-limit control to shut the furnace down
D: Cause the furnace to catch on fire - CORRECT ANSWER -A: Allow combustion
gases to mix with the space air
Gas valves operate on what voltage?
A: 12 volts
B: 24 volts
,C: 120 volts
D: 230 volts - CORRECT ANSWER -B: 24 volts
Mid-efficiency furnaces operate with flue gas temperatures between:
A: 275 and 360 degrees
B: 200 and 500 degrees
C: 100 and 275 degrees
D: 80 and 100 degrees - CORRECT ANSWER -A: 275 and 360 degrees
High-efficiency furnaces operate with flue gas temperatures between:
A: 275 and 360 degrees
B: 200 and 500 degrees
C: 100 and 275 degrees
, D: 80 and 100 degrees - CORRECT ANSWER -C: 100 and 275 degrees
"B" vent is:
A: Hard, inflexible white plastic vent tubing able to withstand temperatures up to
325 degrees F
B: Hard, inflexible white plastic vent tubing able to withstand temperatures up to
400 degrees F
C: Single wall sheet metal vent pipe
D: Double wall sheet metal vent pipe - CORRECT ANSWER -D: Double wall sheet
metal vent pipe
Latent heat is:
A: Heat that causes a change in temperature with no change in state
B: Heat that causes a change in state with no change in temperature
