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NATE Air Distribution exam (actual 2025/2026) with
100% verified correct answers
What is the function of a transformer in a gas furnace? - (answer)It reduces line
voltage to control voltage.
On a call for heat, the thermostat energizes the __________ terminal -
(answer)W
What is the function of the inducer in a gas furnace? - (answer)It brings in air for
combustion
Rollout limit switches are located in the __________. - (answer)Burner area
Which of the following statements is true regarding inshot burners? -
(answer)They require a seperate flame carryover channel.
A furnace with an AFUE of 90% or higher has ___________. - (answer)Both
primary and secondary heat exchangers.
For natural gas applications, an ideal line pressure is __________ - (answer)7.0 in.
w.g.
For natural gas applications, the manifold pressure typically is set at
_____________. - (answer)3.5 in. wg.
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In a gas furnace application, "ESP" refers to the ___________. -
(answer)resistance to air flow in the supply and return ducts
What is the first step in the sequence of operation for a typical gas ignition
system? - (answer)The thermostat closes the R-W circuit
In a counterflow furnace, air passes from ___________. - (answer)The top to the
bottom of the furnace
Regarding combustion air requirements, a "confined space" is defined as a space
who's volume is ___________ per 1,000 BTUH of the combined input rating of all
appliances installed in that space. - (answer)Less than 50 ft.^3
Oil furnaces are vented with _________ venting material. - (answer)Type L
The purpose of a CAD cell in an oil furnace is to _______________. -
(answer)Prove the presence of flame
Normal CAD cell resistance is ______________ with flame present. - (answer)Less
than 1,600 Ohms
Oil furnaces typically are designed to burn _____________. - (answer)#2 fuel oil
only
NATE Air Distribution exam (actual 2025/2026) with
100% verified correct answers
What is the function of a transformer in a gas furnace? - (answer)It reduces line
voltage to control voltage.
On a call for heat, the thermostat energizes the __________ terminal -
(answer)W
What is the function of the inducer in a gas furnace? - (answer)It brings in air for
combustion
Rollout limit switches are located in the __________. - (answer)Burner area
Which of the following statements is true regarding inshot burners? -
(answer)They require a seperate flame carryover channel.
A furnace with an AFUE of 90% or higher has ___________. - (answer)Both
primary and secondary heat exchangers.
For natural gas applications, an ideal line pressure is __________ - (answer)7.0 in.
w.g.
For natural gas applications, the manifold pressure typically is set at
_____________. - (answer)3.5 in. wg.
, 2|Page
In a gas furnace application, "ESP" refers to the ___________. -
(answer)resistance to air flow in the supply and return ducts
What is the first step in the sequence of operation for a typical gas ignition
system? - (answer)The thermostat closes the R-W circuit
In a counterflow furnace, air passes from ___________. - (answer)The top to the
bottom of the furnace
Regarding combustion air requirements, a "confined space" is defined as a space
who's volume is ___________ per 1,000 BTUH of the combined input rating of all
appliances installed in that space. - (answer)Less than 50 ft.^3
Oil furnaces are vented with _________ venting material. - (answer)Type L
The purpose of a CAD cell in an oil furnace is to _______________. -
(answer)Prove the presence of flame
Normal CAD cell resistance is ______________ with flame present. - (answer)Less
than 1,600 Ohms
Oil furnaces typically are designed to burn _____________. - (answer)#2 fuel oil
only
