NATE Gas & Heat Exam NEWEST 2025 COMPLETE
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!!
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.
When suspended with metal strap and no saddle, flexible duct should be: - CORRECT ANSWER-
Supported with a minimum strap width of 1/2"
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
Leveling of a Mercury bulb is: - CORRECT ANSWER- Critical
Spray-type atomizing humidifiers are installed to: - CORRECT ANSWER- Discharge moisture into
the supply duct
,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.
The LP gas manifold pressure is commonly: - CORRECT ANSWER- 10 to 11 in. W.C.
The polarity of a 120V gas furnace equipped with electronic flame rectification is important
because: - CORRECT ANSWER- The ignition control may not prove flame
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.
The setting on a 4 speed PSC blower motor can be changed by changing the: - CORRECT
ANSWER- Motor tap connection
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.
The flame pattern a technician would expect to see on a properly operating single stage gas
furnace equipped with "in shot" type burner is a: - CORRECT ANSWER- Hard and forceful flame
with a light blue appearance and little to no yellow
Compressed air is recommended for a: - CORRECT ANSWER- Pressurization leak test of fuel gas
pipe
Diaphragm type differential pressure gauge is used to: - CORRECT ANSWER- Measure air
pressure
,What precautions are required when mounting any gas furnace on a wood platform in an attic?
- CORRECT ANSWER- None
The gas control valve may be damaged if exposed to an inlet pressure above: - CORRECT
ANSWER- 14 in. W.C.
How many elbows and joints should a vent connector have: - CORRECT ANSWER- As few as
possible to reduce resistance of flue gases
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.
The pressure reading on a manometer is expressed in: - CORRECT ANSWER- Inches of water
A technician measures the return air temperature of a 100,000 BTU output gas furnace to be 65
degrees and the supply side air temperature is 135 degrees: - CORRECT ANSWER- The CFM
would be 1323
A dirty or clogged air filter in an operating gas furnace can cause an: - CORRECT ANSWER-
Increase temperature rise
Bent vanes on a direct drive blower wheel in a gas furnace can cause a: - CORRECT ANSWER-
Loss in airflow, excessive blower motor wear, and increase noise
A gas clothes dryer can interfere with the operation of a nearby natural draft gas furnace with
an atmospheric burner by: - CORRECT ANSWER- Stealing combustion air preventing complete
fuel burning
, During a preventive maintenance check of a gas furnace: - CORRECT ANSWER- Ductwork should
always be checked for leaks and damage
When performing a cycle check during a preventive maintenance call, the technician should: -
CORRECT ANSWER- First, check with owner for equipment performance
Next, turn the unit off at the thermostat system switch
Next, set fan switch to ON and check that the blower is running
The measurements required to calculate the CFM of a gas furnace are: - CORRECT ANSWER-
Entering air temperature
Leaving air temperature
Outdoor ambient and rated capacity
The reason for checking the temperature rise across the heat exchanger of a gas furnace is to: -
CORRECT ANSWER- Compare temperature differential to nameplate rating
The technician is servicing a gas furnace located in a basement and the complaint is "not
enough heat". The following conditions exist: Properly sized furnace is operating correctly;
Temperature rise is within specification; Filter is clean and CFM from blower is running. -
CORRECT ANSWER- The most likely problem with this system is the air side is leaking at one or
more supply ducts
The technician is checking the operation of an induced draft furnace with an atmospheric
burner and a direct ignition system. On a call for heat the: Vent blower comes on; Igniter glows;
Main burner does not light; - CORRECT ANSWER- The next check would be the gas supply and/or
gas valve
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!!
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.
When suspended with metal strap and no saddle, flexible duct should be: - CORRECT ANSWER-
Supported with a minimum strap width of 1/2"
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
Leveling of a Mercury bulb is: - CORRECT ANSWER- Critical
Spray-type atomizing humidifiers are installed to: - CORRECT ANSWER- Discharge moisture into
the supply duct
,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.
The LP gas manifold pressure is commonly: - CORRECT ANSWER- 10 to 11 in. W.C.
The polarity of a 120V gas furnace equipped with electronic flame rectification is important
because: - CORRECT ANSWER- The ignition control may not prove flame
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.
The setting on a 4 speed PSC blower motor can be changed by changing the: - CORRECT
ANSWER- Motor tap connection
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.
The flame pattern a technician would expect to see on a properly operating single stage gas
furnace equipped with "in shot" type burner is a: - CORRECT ANSWER- Hard and forceful flame
with a light blue appearance and little to no yellow
Compressed air is recommended for a: - CORRECT ANSWER- Pressurization leak test of fuel gas
pipe
Diaphragm type differential pressure gauge is used to: - CORRECT ANSWER- Measure air
pressure
,What precautions are required when mounting any gas furnace on a wood platform in an attic?
- CORRECT ANSWER- None
The gas control valve may be damaged if exposed to an inlet pressure above: - CORRECT
ANSWER- 14 in. W.C.
How many elbows and joints should a vent connector have: - CORRECT ANSWER- As few as
possible to reduce resistance of flue gases
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.
The pressure reading on a manometer is expressed in: - CORRECT ANSWER- Inches of water
A technician measures the return air temperature of a 100,000 BTU output gas furnace to be 65
degrees and the supply side air temperature is 135 degrees: - CORRECT ANSWER- The CFM
would be 1323
A dirty or clogged air filter in an operating gas furnace can cause an: - CORRECT ANSWER-
Increase temperature rise
Bent vanes on a direct drive blower wheel in a gas furnace can cause a: - CORRECT ANSWER-
Loss in airflow, excessive blower motor wear, and increase noise
A gas clothes dryer can interfere with the operation of a nearby natural draft gas furnace with
an atmospheric burner by: - CORRECT ANSWER- Stealing combustion air preventing complete
fuel burning
, During a preventive maintenance check of a gas furnace: - CORRECT ANSWER- Ductwork should
always be checked for leaks and damage
When performing a cycle check during a preventive maintenance call, the technician should: -
CORRECT ANSWER- First, check with owner for equipment performance
Next, turn the unit off at the thermostat system switch
Next, set fan switch to ON and check that the blower is running
The measurements required to calculate the CFM of a gas furnace are: - CORRECT ANSWER-
Entering air temperature
Leaving air temperature
Outdoor ambient and rated capacity
The reason for checking the temperature rise across the heat exchanger of a gas furnace is to: -
CORRECT ANSWER- Compare temperature differential to nameplate rating
The technician is servicing a gas furnace located in a basement and the complaint is "not
enough heat". The following conditions exist: Properly sized furnace is operating correctly;
Temperature rise is within specification; Filter is clean and CFM from blower is running. -
CORRECT ANSWER- The most likely problem with this system is the air side is leaking at one or
more supply ducts
The technician is checking the operation of an induced draft furnace with an atmospheric
burner and a direct ignition system. On a call for heat the: Vent blower comes on; Igniter glows;
Main burner does not light; - CORRECT ANSWER- The next check would be the gas supply and/or
gas valve
