NATE Gas & Heat Newest Exam / NATE Gas & Heat
Preparation/NATE Gas & Heat Exam Practice Exam With
500 Questions And Correct Answers| Brand New Version!
What precautions are required when mounting any gas furnace on a wood
platform in an attic? - ans -None
The gas control valve may be damaged if exposed to an inlet pressure above: - ans
-14 in. W.C.
How many elbows and joints should a vent connector have: - ans -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? - ans -Under no conditions may you use the
water heater exhaust vent.
How may a technician terminate the intake and exhaust for proper operation of a
high efficiency gas furnace when using scheduled 40 PVC pipe: - ans -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: - ans -
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: - ans -Leave adequate space should be
allowed for addition of a coil in the future when feasible
Leveling of a Mercury bulb is: - ans -Critical
Spray-type atomizing humidifiers are installed to: - ans -Discharge moisture into
the supply duct
Electronic air cleaners (EAC) installed in a gas furnace system should be wired so
they: - ans -Only operate any time the EAC On-Off switch is turned to ON.
The LP gas manifold pressure is commonly: - ans -10 to 11 in. W.C.
,The polarity of a 120V gas furnace equipped with electronic flame rectification is
important because: - ans -The ignition control may not prove flame
Using a voltmeter, a technician can determine voltage drop at a gas furnace: - ans
-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: - ans
-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: - ans -
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: - ans -Hard and
forceful flame with a light blue appearance and little to no yellow
Compressed air is recommended for a: - ans -Pressurization leak test of fuel gas
pipe
Diaphragm type differential pressure gauge is used to: - ans -Measure air pressure
The pressure reading on a manometer is expressed in: - ans -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: - ans
-The CFM would be 1323
A dirty or clogged air filter in an operating gas furnace can cause an: - ans -
Increase temperature rise
Bent vanes on a direct drive blower wheel in a gas furnace can cause a: - ans -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: - ans -Stealing combustion air preventing
complete fuel burning
During a preventive maintenance check of a gas furnace: - ans -Ductwork should
always be checked for leaks and damage
When performing a cycle check during a preventive maintenance call, the
technician should: - ans -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: - ans -
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: - ans -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. - ans -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; - ans -The next check
would be the gas supply and/or gas valve
The complaint is that there is static electricity throughout the house. The home
has a bypass humidifier. The technician has checked the humidistat and verified
that it is set properly. - ans -The next check would be to see if the humidifier
damper is open.
, A customer complains the unit is "blowing cold air". The technician determines
that the problem occurs at the end of the heating sequence. The furnace used an
electronic integrated blower control. - ans -The likely problem with the system is
the blower off delay is set too long.
Undersized ductwork causes: - ans -High sound levels; Insufficient air quantities;
High static pressure
For accuracy, the preferred locations for the temperature probes when measuring
temperature rise across a heat exchanger in a gas furnace is to: - ans -Read inlet
temp in the return plenum as close as possible to the heat exchanger. Read outlet
temp in supply plenum as close as possible, but beyond "line of sight" to the heat
exchanger.
A system airflow check determines that supply static is 0.15 in. W.C. And return
static is a -0.55 in. W.C. These readings tell the technician: - ans -The difference
between supply static and return static is unacceptably low.
The following measurements would be needed to properly evaluate a complaint
of "drafty" operation with a gas heating system: - ans -System TD, Drop and static
pressure
A furnace is inoperative because of a failure in the ignition sequence at the flame
proving stage. To check the flame proving circuit the technician would: - ans -
Connect a microampmeter set to DC microamps in the sensor circuit and operate
the furnace.
A technician receives a call that a gas furnace is running constantly in heating and
cannot be shut off. While checking the thermostat, the technician observes the
burner shuts off by removing the wire on the R terminal on the thermostat
subbase. - ans -Most likely there is a short in the thermostat subbase
The continuity of a fuse should be tested by: - ans -Checking resistance with
power off
A standing pilot furnace uses a relay for controlling the supply blower. On a call
for heat, the burner lights, the fan control closes, but the blower does not run. A
Preparation/NATE Gas & Heat Exam Practice Exam With
500 Questions And Correct Answers| Brand New Version!
What precautions are required when mounting any gas furnace on a wood
platform in an attic? - ans -None
The gas control valve may be damaged if exposed to an inlet pressure above: - ans
-14 in. W.C.
How many elbows and joints should a vent connector have: - ans -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? - ans -Under no conditions may you use the
water heater exhaust vent.
How may a technician terminate the intake and exhaust for proper operation of a
high efficiency gas furnace when using scheduled 40 PVC pipe: - ans -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: - ans -
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: - ans -Leave adequate space should be
allowed for addition of a coil in the future when feasible
Leveling of a Mercury bulb is: - ans -Critical
Spray-type atomizing humidifiers are installed to: - ans -Discharge moisture into
the supply duct
Electronic air cleaners (EAC) installed in a gas furnace system should be wired so
they: - ans -Only operate any time the EAC On-Off switch is turned to ON.
The LP gas manifold pressure is commonly: - ans -10 to 11 in. W.C.
,The polarity of a 120V gas furnace equipped with electronic flame rectification is
important because: - ans -The ignition control may not prove flame
Using a voltmeter, a technician can determine voltage drop at a gas furnace: - ans
-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: - ans
-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: - ans -
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: - ans -Hard and
forceful flame with a light blue appearance and little to no yellow
Compressed air is recommended for a: - ans -Pressurization leak test of fuel gas
pipe
Diaphragm type differential pressure gauge is used to: - ans -Measure air pressure
The pressure reading on a manometer is expressed in: - ans -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: - ans
-The CFM would be 1323
A dirty or clogged air filter in an operating gas furnace can cause an: - ans -
Increase temperature rise
Bent vanes on a direct drive blower wheel in a gas furnace can cause a: - ans -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: - ans -Stealing combustion air preventing
complete fuel burning
During a preventive maintenance check of a gas furnace: - ans -Ductwork should
always be checked for leaks and damage
When performing a cycle check during a preventive maintenance call, the
technician should: - ans -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: - ans -
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: - ans -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. - ans -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; - ans -The next check
would be the gas supply and/or gas valve
The complaint is that there is static electricity throughout the house. The home
has a bypass humidifier. The technician has checked the humidistat and verified
that it is set properly. - ans -The next check would be to see if the humidifier
damper is open.
, A customer complains the unit is "blowing cold air". The technician determines
that the problem occurs at the end of the heating sequence. The furnace used an
electronic integrated blower control. - ans -The likely problem with the system is
the blower off delay is set too long.
Undersized ductwork causes: - ans -High sound levels; Insufficient air quantities;
High static pressure
For accuracy, the preferred locations for the temperature probes when measuring
temperature rise across a heat exchanger in a gas furnace is to: - ans -Read inlet
temp in the return plenum as close as possible to the heat exchanger. Read outlet
temp in supply plenum as close as possible, but beyond "line of sight" to the heat
exchanger.
A system airflow check determines that supply static is 0.15 in. W.C. And return
static is a -0.55 in. W.C. These readings tell the technician: - ans -The difference
between supply static and return static is unacceptably low.
The following measurements would be needed to properly evaluate a complaint
of "drafty" operation with a gas heating system: - ans -System TD, Drop and static
pressure
A furnace is inoperative because of a failure in the ignition sequence at the flame
proving stage. To check the flame proving circuit the technician would: - ans -
Connect a microampmeter set to DC microamps in the sensor circuit and operate
the furnace.
A technician receives a call that a gas furnace is running constantly in heating and
cannot be shut off. While checking the thermostat, the technician observes the
burner shuts off by removing the wire on the R terminal on the thermostat
subbase. - ans -Most likely there is a short in the thermostat subbase
The continuity of a fuse should be tested by: - ans -Checking resistance with
power off
A standing pilot furnace uses a relay for controlling the supply blower. On a call
for heat, the burner lights, the fan control closes, but the blower does not run. A
