Page 1 of 44
2026 NATE MAXIMIZE GAS FURNACE
SERVICE EXAM COMPLETE CURRENT
TESTING QUESTIONS AND DETAILED
CORRECT ANSWERS (VERIFIED)
GUARANTEED PASS/TOP-RATED A+.
NATE
your success on the NATE (North American Technician
Excellence) Gas Furnace Service certification exam with
focused preparation that strengthens your understanding of
furnace operation, combustion analysis, ignition systems, heat
exchanger inspection, and safety protocols for residential and
light commercial units. It is specifically designed for HVAC
technicians seeking to validate their skills in installing,
maintaining, and troubleshooting gas-fired furnaces.
Why is operating sound a consideration in the location of the
heating unit ✓ ✓...... ANSWER ....... Excessive noise
could be disruptive to the customer
The leakage of air into a conditioned space is referred to as
✓ ✓...... ANSWER ....... Infiltration
, Page 2 of 44
Which of the following is a cause for blower belt noise ✓
✓...... ANSWER ....... Worn pulley
A wet bulb reading that is very close to the dry bulb reading
from the same instrument indicates that ✓ ✓...... ANSWER
....... Relative humidity is very high
A technician is responding to a report of drafty air in a room
during the heating season. The technician, using air
measuring instruments, writes down the following reading:
discharge air velocity = 815 FPM, Supply temperature = 110F,
air volume = 150 CFM From these readings the technician
has concluded that the problem is ✓ ✓...... ANSWER .......
Register velocity is too high
Forced air residential/light commercial gas furnaces provide
heat by circulating air across a ✓ ✓...... ANSWER .......
Heat exchanger
Heat always moves to equalize temperature. Why isn't all the
air in a room the same temperature ✓ ✓...... ANSWER .......
, Page 3 of 44
Convection moves warmer air to the ceiling as it is added to
a space
When a gas furnace is installed with an air conditioning coil,
the coil is installed so that ✓ ✓...... ANSWER ....... Air
passes across through the heat exchanger first
The secondary condensate drain of an air conditioning coil
mounted with a horizontal gas furnace in the attic must
always be connected ✓ ✓...... ANSWER ....... To a
location readily visible and according to local code
What role does oxygen play in the proper combustion of
natural gas ✓ ✓...... ANSWER ....... It combines with the
carbon form carbon dioxide and with the hydrogen to form
water vapor
Some steel heat exchangers are coated to prevent ✓ ✓......
ANSWER ....... Rusting of the heat exchanger
The voltage most often used to power a residential package
unit is ✓ ✓...... ANSWER ....... 120V +/_ 10
, Page 4 of 44
In order to ensure adequate combustion air is available in
crawl space applications of direct vented gas furnaces there
must be ✓ ✓...... ANSWER ....... An air intake connected
from outdoors to the furnace combustion air intake
When a direct vent gas furnace is located in a crawlspace,
the intake must be located so that ✓ ✓...... ANSWER .......
It is in the same pressure zone as that used for exhaust
An 80% efficiency gas furnace, mounted in a crawlspace,
draws its combustion air from what location ✓ ✓......
ANSWER ....... The space surrounding the furnace
What precautions, if any, must be taken when installing a
downflow gas furnace ✓ ✓...... ANSWER ....... Downflow
gas furnaces may be installed if a non-combustible base is
used
A "cross break" made on all sides of any rectangular section
of the metal duct will ✓ ✓...... ANSWER ....... Increase
rigidity and reduce vibration
2026 NATE MAXIMIZE GAS FURNACE
SERVICE EXAM COMPLETE CURRENT
TESTING QUESTIONS AND DETAILED
CORRECT ANSWERS (VERIFIED)
GUARANTEED PASS/TOP-RATED A+.
NATE
your success on the NATE (North American Technician
Excellence) Gas Furnace Service certification exam with
focused preparation that strengthens your understanding of
furnace operation, combustion analysis, ignition systems, heat
exchanger inspection, and safety protocols for residential and
light commercial units. It is specifically designed for HVAC
technicians seeking to validate their skills in installing,
maintaining, and troubleshooting gas-fired furnaces.
Why is operating sound a consideration in the location of the
heating unit ✓ ✓...... ANSWER ....... Excessive noise
could be disruptive to the customer
The leakage of air into a conditioned space is referred to as
✓ ✓...... ANSWER ....... Infiltration
, Page 2 of 44
Which of the following is a cause for blower belt noise ✓
✓...... ANSWER ....... Worn pulley
A wet bulb reading that is very close to the dry bulb reading
from the same instrument indicates that ✓ ✓...... ANSWER
....... Relative humidity is very high
A technician is responding to a report of drafty air in a room
during the heating season. The technician, using air
measuring instruments, writes down the following reading:
discharge air velocity = 815 FPM, Supply temperature = 110F,
air volume = 150 CFM From these readings the technician
has concluded that the problem is ✓ ✓...... ANSWER .......
Register velocity is too high
Forced air residential/light commercial gas furnaces provide
heat by circulating air across a ✓ ✓...... ANSWER .......
Heat exchanger
Heat always moves to equalize temperature. Why isn't all the
air in a room the same temperature ✓ ✓...... ANSWER .......
, Page 3 of 44
Convection moves warmer air to the ceiling as it is added to
a space
When a gas furnace is installed with an air conditioning coil,
the coil is installed so that ✓ ✓...... ANSWER ....... Air
passes across through the heat exchanger first
The secondary condensate drain of an air conditioning coil
mounted with a horizontal gas furnace in the attic must
always be connected ✓ ✓...... ANSWER ....... To a
location readily visible and according to local code
What role does oxygen play in the proper combustion of
natural gas ✓ ✓...... ANSWER ....... It combines with the
carbon form carbon dioxide and with the hydrogen to form
water vapor
Some steel heat exchangers are coated to prevent ✓ ✓......
ANSWER ....... Rusting of the heat exchanger
The voltage most often used to power a residential package
unit is ✓ ✓...... ANSWER ....... 120V +/_ 10
, Page 4 of 44
In order to ensure adequate combustion air is available in
crawl space applications of direct vented gas furnaces there
must be ✓ ✓...... ANSWER ....... An air intake connected
from outdoors to the furnace combustion air intake
When a direct vent gas furnace is located in a crawlspace,
the intake must be located so that ✓ ✓...... ANSWER .......
It is in the same pressure zone as that used for exhaust
An 80% efficiency gas furnace, mounted in a crawlspace,
draws its combustion air from what location ✓ ✓......
ANSWER ....... The space surrounding the furnace
What precautions, if any, must be taken when installing a
downflow gas furnace ✓ ✓...... ANSWER ....... Downflow
gas furnaces may be installed if a non-combustible base is
used
A "cross break" made on all sides of any rectangular section
of the metal duct will ✓ ✓...... ANSWER ....... Increase
rigidity and reduce vibration
