G2 PREP TEST ACTUAL PAPER 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◉ Flame rods (flame rectifiers) utilize:
A) Milliamps
B) millivolts
C) microamps
D) microvolts. Answer: C) Microamps
◉ The flue and ventilation effect in a building causes:
A) infiltration of air to replace that which is exhausted through vents
and exhaust devices
B) exfiltration of air due to the positive pressure created by the
venting of combustion gases and exhaustive devices
C) unnecessary heat loss and should be prevented by sealing the
building
D) negative pressures on the upper floors compared to lower floors
and basements. Answer: A) infiltration of air to replace that which is
exhausted through vents and exhaust devices
,◉ Which is the most common cause of flue gas spillage from gas
appliances?
A) Positive air pressure caused by mechanical systems
B) Negative air pressure caused by mechanical systems
C) cracked or leaking heat exchangers
D) chimney which are too short. Answer: B) Negative air pressure
caused by mechanical systems
◉ Which device shuts off the spark ignite in a spark ignition dryer
after proper ignition?
A) spark sensor
B) ignition sensor
C) limit switch
D) main burner switch. Answer: B) ignition sensor
◉ A propane vaporizer shall not raise the pressure in a tank in
excess of:
A) the design pressure of the tank
B) 100psig (690kPa)
C) 215 psig (1480kPa)
,D) 375 psig (2580kPa). Answer: C) 215 psig (1480kPa)
◉ the maximum gas pressure allowed in a recreational vehicle or
mobile home is:
A) 11"w.c. (2.7kPa)
B) 13" w.c. (3.2kPa)
C) 1 psig (6.9kPa)
D) 20psig (138kPa). Answer: B) 13" w.c. (3.2kPa)
◉ When the required minimum clearance for a vent connector is 9"
(228 mm) to combustible material with no protection, what is the
acceptable method to reduce the clearance by 3" (76 mm)?
A. use 0.05" (12 mm) insulating millboard spaced out 0.05 (12 mm)
with noncombustible spacers
B. use 0.25" (6 mm) insulating millboard spaced out 1" (25 mm)
C. use 22 gauge sheet metal attached to the hot side of the-
combustible material
D. use 28 gauge sheet metal spaced out 1" (25 mm) from the
combustible material. Answer: B) use 0.25" (6 mm) insulating
millboard spaced out 1" (25 mm)
◉ A customer complains that the pilot goes out every once in a
while. This is the 2nd service call for this problem this month. When
, the pilot is reestablished, the closed circuit millivolt test stays steady
at 14 millivolts. The magnet drops out at 4 millivolts. What should be
done next?
A) Replace the gas valve because the magnet is weak
B) Clean and adjust the pilot and burner(s)
C) Replace the thermocouple
D) check for another problem such as down draft or pilot position.
Answer: D) check for another problem such as down draft or pilot
position
◉ The type of heat exchanger associated with forced air
combination system is:
A) a water to air type
B) an air to water type
C) a radiant type
QUESTIONS WITH SOLUTIONS GRADED A+
◉ Flame rods (flame rectifiers) utilize:
A) Milliamps
B) millivolts
C) microamps
D) microvolts. Answer: C) Microamps
◉ The flue and ventilation effect in a building causes:
A) infiltration of air to replace that which is exhausted through vents
and exhaust devices
B) exfiltration of air due to the positive pressure created by the
venting of combustion gases and exhaustive devices
C) unnecessary heat loss and should be prevented by sealing the
building
D) negative pressures on the upper floors compared to lower floors
and basements. Answer: A) infiltration of air to replace that which is
exhausted through vents and exhaust devices
,◉ Which is the most common cause of flue gas spillage from gas
appliances?
A) Positive air pressure caused by mechanical systems
B) Negative air pressure caused by mechanical systems
C) cracked or leaking heat exchangers
D) chimney which are too short. Answer: B) Negative air pressure
caused by mechanical systems
◉ Which device shuts off the spark ignite in a spark ignition dryer
after proper ignition?
A) spark sensor
B) ignition sensor
C) limit switch
D) main burner switch. Answer: B) ignition sensor
◉ A propane vaporizer shall not raise the pressure in a tank in
excess of:
A) the design pressure of the tank
B) 100psig (690kPa)
C) 215 psig (1480kPa)
,D) 375 psig (2580kPa). Answer: C) 215 psig (1480kPa)
◉ the maximum gas pressure allowed in a recreational vehicle or
mobile home is:
A) 11"w.c. (2.7kPa)
B) 13" w.c. (3.2kPa)
C) 1 psig (6.9kPa)
D) 20psig (138kPa). Answer: B) 13" w.c. (3.2kPa)
◉ When the required minimum clearance for a vent connector is 9"
(228 mm) to combustible material with no protection, what is the
acceptable method to reduce the clearance by 3" (76 mm)?
A. use 0.05" (12 mm) insulating millboard spaced out 0.05 (12 mm)
with noncombustible spacers
B. use 0.25" (6 mm) insulating millboard spaced out 1" (25 mm)
C. use 22 gauge sheet metal attached to the hot side of the-
combustible material
D. use 28 gauge sheet metal spaced out 1" (25 mm) from the
combustible material. Answer: B) use 0.25" (6 mm) insulating
millboard spaced out 1" (25 mm)
◉ A customer complains that the pilot goes out every once in a
while. This is the 2nd service call for this problem this month. When
, the pilot is reestablished, the closed circuit millivolt test stays steady
at 14 millivolts. The magnet drops out at 4 millivolts. What should be
done next?
A) Replace the gas valve because the magnet is weak
B) Clean and adjust the pilot and burner(s)
C) Replace the thermocouple
D) check for another problem such as down draft or pilot position.
Answer: D) check for another problem such as down draft or pilot
position
◉ The type of heat exchanger associated with forced air
combination system is:
A) a water to air type
B) an air to water type
C) a radiant type
