Page 1 of 122
NATE Gas Heating EXAM NEWEST UPDATE
2026-2027 ALL QUESTIONS AND DETAILED
SOLUTIONS
Question: What type of burners are commonly used with induced-draft gas furnaces?
a. Gun style
b. Pot style
c. Ribbon
d. Inshot - CORRECT ANSWER✔✔d
Question: What is the typical color of a properly burning gas flame?
a. Blue
b. Orange
c. Red
d. Yellow - CORRECT ANSWER✔✔a
, Page 2 of 122
Question: In a gas furnace, primary combustion air is introduced in the _______.
a. burner prior to ignition
b. burner after ignition
c. gas line
d. heat exchanger - CORRECT ANSWER✔✔a
Question: A "dumbbell" style CO2 tester ________.
a. contains a test fluid that absorbs CO2
b. measures CO2 in parts per million
c. provides a digital readout
d. requires a power supply - CORRECT ANSWER✔✔a
Question: Useful heat output, expressed as a percentage of the total burner input, is known as
the ______ of a gas furnace.
a. combustion efficiency
b. fuel efficiency
c. heat exchanger performance factor
d. heating coefficient - CORRECT ANSWER✔✔a
, Page 3 of 122
Question: Which type of ignition system uses a thermocouple?
a. Direct ignition
b. Hot-surface
c. Intermittent ignition
d. Standing pilot - CORRECT ANSWER✔✔d
Question: The blower in a standing pilot furnace is generally started by a(n) ______.
a. differential pressure switch
b. ignition module
c. temperature switch
d. time-delay relay - CORRECT ANSWER✔✔c
Question: A furnace with an induced-draft fan uses a _______ to prove air flow.
a. high-pressure switch
b. low-pressure switch
c. pressure differential switch
, Page 4 of 122
d. sail switch - CORRECT ANSWER✔✔c
Q:In a modern gas furnace, the component that separates the combustion gases from the
supply air is the ______.
a. gas valve
b. heat exchanger
c. inducer fan
d. plenum box - CORRECT ANSWER✔✔b (heat exchanger)
Question: What type of furnace moves warm air through the conditioned space without a fan?
a. Gravity
b. Horizontal
c. Lowboy
d. Upflow - CORRECT ANSWER✔✔a (Gravity)
Question: Furnace heat exchangers generally are made of ______.
a. ceramic
NATE Gas Heating EXAM NEWEST UPDATE
2026-2027 ALL QUESTIONS AND DETAILED
SOLUTIONS
Question: What type of burners are commonly used with induced-draft gas furnaces?
a. Gun style
b. Pot style
c. Ribbon
d. Inshot - CORRECT ANSWER✔✔d
Question: What is the typical color of a properly burning gas flame?
a. Blue
b. Orange
c. Red
d. Yellow - CORRECT ANSWER✔✔a
, Page 2 of 122
Question: In a gas furnace, primary combustion air is introduced in the _______.
a. burner prior to ignition
b. burner after ignition
c. gas line
d. heat exchanger - CORRECT ANSWER✔✔a
Question: A "dumbbell" style CO2 tester ________.
a. contains a test fluid that absorbs CO2
b. measures CO2 in parts per million
c. provides a digital readout
d. requires a power supply - CORRECT ANSWER✔✔a
Question: Useful heat output, expressed as a percentage of the total burner input, is known as
the ______ of a gas furnace.
a. combustion efficiency
b. fuel efficiency
c. heat exchanger performance factor
d. heating coefficient - CORRECT ANSWER✔✔a
, Page 3 of 122
Question: Which type of ignition system uses a thermocouple?
a. Direct ignition
b. Hot-surface
c. Intermittent ignition
d. Standing pilot - CORRECT ANSWER✔✔d
Question: The blower in a standing pilot furnace is generally started by a(n) ______.
a. differential pressure switch
b. ignition module
c. temperature switch
d. time-delay relay - CORRECT ANSWER✔✔c
Question: A furnace with an induced-draft fan uses a _______ to prove air flow.
a. high-pressure switch
b. low-pressure switch
c. pressure differential switch
, Page 4 of 122
d. sail switch - CORRECT ANSWER✔✔c
Q:In a modern gas furnace, the component that separates the combustion gases from the
supply air is the ______.
a. gas valve
b. heat exchanger
c. inducer fan
d. plenum box - CORRECT ANSWER✔✔b (heat exchanger)
Question: What type of furnace moves warm air through the conditioned space without a fan?
a. Gravity
b. Horizontal
c. Lowboy
d. Upflow - CORRECT ANSWER✔✔a (Gravity)
Question: Furnace heat exchangers generally are made of ______.
a. ceramic
