NATE - Gas & Heat Exam Questions and Answers |Fall
2025/2026 Update | 100% Correct Latest
Question 1
What precautions are required when mounting any gas furnace on a wood platform in an attic?
Correct Answer
None
Question 2
The gas control valve may be damaged if exposed to an inlet pressure above:
Correct Answer
14 in. W.C.
Question 3
How many elbows and joints should a vent connector have:
Correct Answer
As few as possible to reduce resistance of flue gases
Page 1 of 36
,Question 4
What conditions, if any may a technician route the exhaust of the furnace into the exhaust vent of the water heater?
Correct Answer
Under no conditions may you use the water heater exhaust vent.
Question 5
How may a technician terminate the intake and exhaust for proper operation of a high efficiency gas furnace when using
scheduled 40 PVC pipe:
Correct Answer
By using the specific manufacturers termination kit or make one to meet their requirements.
Question 6
When suspended with metal strap and no saddle, flexible duct should be:
Correct Answer
Supported with a minimum strap width of 1/2"
Question 7
Installing a gas furnace and not an air conditioner has what affect on the installation of the supply ductwork:
Correct Answer
Leave adequate space should be allowed for addition of a coil in the future when feasible
Page 2 of 36
,Question 8
Leveling of a Mercury bulb is:
Correct Answer
Critical
Question 9
Spray-type atomizing humidifiers are installed to:
Correct Answer
Discharge moisture into the supply duct
Question 10
Electronic air cleaners (EAC) installed in a gas furnace system should be wired so they:
Correct Answer
Only operate any time the EAC On-Off switch is turned to ON.
Question 11
The LP gas manifold pressure is commonly:
Correct Answer
10 to 11 in. W.C.
Page 3 of 36
, Question 12
The polarity of a 120V gas furnace equipped with electronic flame rectification is important because:
Correct Answer
The ignition control may not prove flame
Question 13
Using a voltmeter, a technician can determine voltage drop at a gas furnace:
Correct Answer
With the furnace not operating and then with the furnace operating.
Question 14
The setting on a 4 speed PSC blower motor can be changed by changing the:
Correct Answer
Motor tap connection
Question 15
When starting up a dual system, the temperature rise method for determining airflow cannot be used with compressor
cycle of the heat pump because:
Correct Answer
The capacity of the system varies too much with outdoor temperature.
Page 4 of 36
2025/2026 Update | 100% Correct Latest
Question 1
What precautions are required when mounting any gas furnace on a wood platform in an attic?
Correct Answer
None
Question 2
The gas control valve may be damaged if exposed to an inlet pressure above:
Correct Answer
14 in. W.C.
Question 3
How many elbows and joints should a vent connector have:
Correct Answer
As few as possible to reduce resistance of flue gases
Page 1 of 36
,Question 4
What conditions, if any may a technician route the exhaust of the furnace into the exhaust vent of the water heater?
Correct Answer
Under no conditions may you use the water heater exhaust vent.
Question 5
How may a technician terminate the intake and exhaust for proper operation of a high efficiency gas furnace when using
scheduled 40 PVC pipe:
Correct Answer
By using the specific manufacturers termination kit or make one to meet their requirements.
Question 6
When suspended with metal strap and no saddle, flexible duct should be:
Correct Answer
Supported with a minimum strap width of 1/2"
Question 7
Installing a gas furnace and not an air conditioner has what affect on the installation of the supply ductwork:
Correct Answer
Leave adequate space should be allowed for addition of a coil in the future when feasible
Page 2 of 36
,Question 8
Leveling of a Mercury bulb is:
Correct Answer
Critical
Question 9
Spray-type atomizing humidifiers are installed to:
Correct Answer
Discharge moisture into the supply duct
Question 10
Electronic air cleaners (EAC) installed in a gas furnace system should be wired so they:
Correct Answer
Only operate any time the EAC On-Off switch is turned to ON.
Question 11
The LP gas manifold pressure is commonly:
Correct Answer
10 to 11 in. W.C.
Page 3 of 36
, Question 12
The polarity of a 120V gas furnace equipped with electronic flame rectification is important because:
Correct Answer
The ignition control may not prove flame
Question 13
Using a voltmeter, a technician can determine voltage drop at a gas furnace:
Correct Answer
With the furnace not operating and then with the furnace operating.
Question 14
The setting on a 4 speed PSC blower motor can be changed by changing the:
Correct Answer
Motor tap connection
Question 15
When starting up a dual system, the temperature rise method for determining airflow cannot be used with compressor
cycle of the heat pump because:
Correct Answer
The capacity of the system varies too much with outdoor temperature.
Page 4 of 36
