1|Page
NATE Gas Furnace Service Preparation Version 3
Newest Verified Exam With Complete Questions And
Correct Detailed Answers| Newest Exam!!!
What precautions, if any, must be taken when installing a
gas furnace on a wooden platform in an attic? - Answers-
Use a zero-clearance furnace or add a non-combustible
base
A vent connector should have a as few elbows and joints
as possible to: - Answers-Reduce resistance of flue gases
The gas control valve may be damaged if exposed to an
inlet pressure above - Answers-14in wc
To which thermostat is leveling the most critical: -
Answers-Mercury Bulb
Which of the following is a reason for the thermostat to
short cycle a gas furnace - Answers-A system that is
oversized for the load
,2|Page
When a thermocouple pilot flame is lost on a standing pilot
gas furnace, the primary component which shuts off gas
flow to the main burner is: - Answers-Pilot solenoid
The most important consideration when working on a gas
furnace with ribbon type insertion burners is - Answers-
The individual burners must be mounted in correct
alignment
Primary air is mixed with the gas within the - Answers-
Venturi or throat of the burner
An intermittent pilot gas furnace is one in which a -
Answers-Pilot is lit on every call for heat
The pressure reading on a monometer is expressed in
inches of - Answers-Water
How mush of the end of the thermocouple should be
enveloped by the pilot flame - Answers-3/8 to ½ inch
The LP gas manifold pressure is commonly - Answers-10
to 11in wc
,3|Page
A thermocouple system usually generates its own control
circuit voltage of - Answers-750mv
On a single stage combination gas valve with a
thermocouple flame proving circuit, the main burner gas
flow is - Answers-In series with the pilot gas valve
What do the initials "A.F.U.E" represent - Answers-Annual
Fuel Utilization Efficiency
A technician measures the return air temperature of a
100,000 btuh output gas furnace to be 65 F and the supply
side air temperature is 135F What is the CFM - Answers-
135-65=70TD
70TD x 1.08 = 75.6
100,000/75.6 = 13,227CFM
A furnace is inoperative because of a failure in the ignition
sequence of the flame proving stage. To check the flame
proving circuit the technician would connect a: - Answers-
Microammeter set to DC microamps in the flame rod
circuit and operate the furnace
, 4|Page
A flame on a high efficiency gas furnace is burning
primarily yellow. What, if anything is the problem in this
furnace - Answers-The flame is burning without sufficient
combustion air
A typical four-way multi-positional gas furnace is converted
from up-flow to downflow by - Answers-Turning the
furnace upside down with specified alterations
In the sequence of operation of an induced draft,
intermittent pilot gas furnace, the induced draft motor
starts - Answers-When the thermostat calls for heat
A gas furnace with a standing pilot uses a flame switch for
proving pilot flame. What type of signal is generated by
such a flame er - Answers-NO Signal is generated by a
flame switch, but the flame sensor
Which of the following components is considered a fire
protection device on a gas furnace - Answers-Roll out
switch
NATE Gas Furnace Service Preparation Version 3
Newest Verified Exam With Complete Questions And
Correct Detailed Answers| Newest Exam!!!
What precautions, if any, must be taken when installing a
gas furnace on a wooden platform in an attic? - Answers-
Use a zero-clearance furnace or add a non-combustible
base
A vent connector should have a as few elbows and joints
as possible to: - Answers-Reduce resistance of flue gases
The gas control valve may be damaged if exposed to an
inlet pressure above - Answers-14in wc
To which thermostat is leveling the most critical: -
Answers-Mercury Bulb
Which of the following is a reason for the thermostat to
short cycle a gas furnace - Answers-A system that is
oversized for the load
,2|Page
When a thermocouple pilot flame is lost on a standing pilot
gas furnace, the primary component which shuts off gas
flow to the main burner is: - Answers-Pilot solenoid
The most important consideration when working on a gas
furnace with ribbon type insertion burners is - Answers-
The individual burners must be mounted in correct
alignment
Primary air is mixed with the gas within the - Answers-
Venturi or throat of the burner
An intermittent pilot gas furnace is one in which a -
Answers-Pilot is lit on every call for heat
The pressure reading on a monometer is expressed in
inches of - Answers-Water
How mush of the end of the thermocouple should be
enveloped by the pilot flame - Answers-3/8 to ½ inch
The LP gas manifold pressure is commonly - Answers-10
to 11in wc
,3|Page
A thermocouple system usually generates its own control
circuit voltage of - Answers-750mv
On a single stage combination gas valve with a
thermocouple flame proving circuit, the main burner gas
flow is - Answers-In series with the pilot gas valve
What do the initials "A.F.U.E" represent - Answers-Annual
Fuel Utilization Efficiency
A technician measures the return air temperature of a
100,000 btuh output gas furnace to be 65 F and the supply
side air temperature is 135F What is the CFM - Answers-
135-65=70TD
70TD x 1.08 = 75.6
100,000/75.6 = 13,227CFM
A furnace is inoperative because of a failure in the ignition
sequence of the flame proving stage. To check the flame
proving circuit the technician would connect a: - Answers-
Microammeter set to DC microamps in the flame rod
circuit and operate the furnace
, 4|Page
A flame on a high efficiency gas furnace is burning
primarily yellow. What, if anything is the problem in this
furnace - Answers-The flame is burning without sufficient
combustion air
A typical four-way multi-positional gas furnace is converted
from up-flow to downflow by - Answers-Turning the
furnace upside down with specified alterations
In the sequence of operation of an induced draft,
intermittent pilot gas furnace, the induced draft motor
starts - Answers-When the thermostat calls for heat
A gas furnace with a standing pilot uses a flame switch for
proving pilot flame. What type of signal is generated by
such a flame er - Answers-NO Signal is generated by a
flame switch, but the flame sensor
Which of the following components is considered a fire
protection device on a gas furnace - Answers-Roll out
switch
