GAS FITTER EXAM 2026-2027 NEWEST
QUESTIONS AND CORRECT ANSWERS |
A+ GRADE VERIFIED ANSWERS
The temperature of the water returning from the heating
loop in a combination system employing a water heater for
domestic hot water and space heating must be:
A. higher than the outlet temperature from the water
heater
B. no more than 5°C (9°F) below the outlet temperature
from the water heater
C. lower than the minimum temperature required to
activate the burner
D. at least the set temperature of the domestic hot water
supply Correct answer C
The flow rate of water passing through a heating coil of an
air handler is controlled by the:
A. aquastat on the water heater
B. balancing valve on the heating loop
C. mixing valve on the heating loop
D. mixing valve on the domestic hot water system Correct
answer B
The faster the flow of water through the heating loop of a
combination heating system employing a water heater for
supplying domestic hot water and space heating:
A. The greater the heat transfer to the heated medium
,B. The lower the water temperature drop through the
heating loop
C. The higher the noise level from the pump and piping
system
D. All available choices Correct answer B
A customer complains that the hot water runs out in the
middle of one shower. The water temperature coming out
of the tap is 140 degrees and begins falling within one
minute. After drawing water for 5 minutes the water
temperature at the bottom of the tank is measured at 130
degrees and the burner has not come on. What is the
most likely cause?
A. The temperature control is out of calibration
B. The shower head passes too much water
C. the dip tube is cracked or broken
D. The temperature sensor is in the wrong location Correct
answer A
As the outlet temperature decreases from a water heater
to the heating loop in a combination system the:
A. Heating output from the air handler decreases
B. Heating output from the air handler increases
C. Rate of heat transfer from the water to air increases
D. Greater the temperature drop through the heating loop
Correct answer A
On a hydronic heater system what control responds to a
load change?
A. Low water cut off
B. Expansion tank
,C. Flow switch
D. Aquastat Correct answer C
Which of the hydronic controls listed below de-energizes
the main burner if the operating control fails in the closed
position?
A. Low limit control
B. Temperature and pressure relief valve
C. High limit control
D. Flow switch Correct answer C
The purpose of mixing valve on a combination system
employing a water heater to provide water for potable use
and provide space heating is to
A. Mix hot water with cold water in the heating loop
B. Mix cold water with the hot water supply to the domestic
plumbing system to maintain a consistent temperature of
domestic hot water
C. Mix cold water with the hot water supply to the heating
loop to maintain a consistent temperature of water in the
heating loop
D. Return some of the hot water to the tank so that it does
not run out of water Correct answer C
A customer complains that the pilot goes out every once in
a while. This is the second service call for this problem this
month. When the pilot is re-established, 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 burners
, C. Replace the thermocouple
D. Check for another problem such as down draft or pilot
position Correct answer D
Combination systems are sized to deliver __________ of
the calculated heat loss of the building.
A. 90%
B. 95% to 105%
C. 120%
D. 200% Correct answer C
The most likely cause of an intermittent hissing sound "like
water dripping on something hot" coming from a water
heater is:
A. an intermittent leak in the flue that seals once the tank
heats up
B. Condensation in the flue passage caused by drawing
water from the tank when the hot water has been depleted
C. Condensation in the flue passage caused by high
humidity in the combustion air supply to the water heater
D. Condensation in the flue passage caused by high
moisture content in the as supply Correct answer B
Why is there a low limit on a hot water tank which supplies
both space heating and domestic hot water?
A. To prevent rusting in the system
B. To prevent freeze up
C. To reduce oil consumption
D. To assure a constant supply of domestic hot water
Correct answer D
QUESTIONS AND CORRECT ANSWERS |
A+ GRADE VERIFIED ANSWERS
The temperature of the water returning from the heating
loop in a combination system employing a water heater for
domestic hot water and space heating must be:
A. higher than the outlet temperature from the water
heater
B. no more than 5°C (9°F) below the outlet temperature
from the water heater
C. lower than the minimum temperature required to
activate the burner
D. at least the set temperature of the domestic hot water
supply Correct answer C
The flow rate of water passing through a heating coil of an
air handler is controlled by the:
A. aquastat on the water heater
B. balancing valve on the heating loop
C. mixing valve on the heating loop
D. mixing valve on the domestic hot water system Correct
answer B
The faster the flow of water through the heating loop of a
combination heating system employing a water heater for
supplying domestic hot water and space heating:
A. The greater the heat transfer to the heated medium
,B. The lower the water temperature drop through the
heating loop
C. The higher the noise level from the pump and piping
system
D. All available choices Correct answer B
A customer complains that the hot water runs out in the
middle of one shower. The water temperature coming out
of the tap is 140 degrees and begins falling within one
minute. After drawing water for 5 minutes the water
temperature at the bottom of the tank is measured at 130
degrees and the burner has not come on. What is the
most likely cause?
A. The temperature control is out of calibration
B. The shower head passes too much water
C. the dip tube is cracked or broken
D. The temperature sensor is in the wrong location Correct
answer A
As the outlet temperature decreases from a water heater
to the heating loop in a combination system the:
A. Heating output from the air handler decreases
B. Heating output from the air handler increases
C. Rate of heat transfer from the water to air increases
D. Greater the temperature drop through the heating loop
Correct answer A
On a hydronic heater system what control responds to a
load change?
A. Low water cut off
B. Expansion tank
,C. Flow switch
D. Aquastat Correct answer C
Which of the hydronic controls listed below de-energizes
the main burner if the operating control fails in the closed
position?
A. Low limit control
B. Temperature and pressure relief valve
C. High limit control
D. Flow switch Correct answer C
The purpose of mixing valve on a combination system
employing a water heater to provide water for potable use
and provide space heating is to
A. Mix hot water with cold water in the heating loop
B. Mix cold water with the hot water supply to the domestic
plumbing system to maintain a consistent temperature of
domestic hot water
C. Mix cold water with the hot water supply to the heating
loop to maintain a consistent temperature of water in the
heating loop
D. Return some of the hot water to the tank so that it does
not run out of water Correct answer C
A customer complains that the pilot goes out every once in
a while. This is the second service call for this problem this
month. When the pilot is re-established, 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 burners
, C. Replace the thermocouple
D. Check for another problem such as down draft or pilot
position Correct answer D
Combination systems are sized to deliver __________ of
the calculated heat loss of the building.
A. 90%
B. 95% to 105%
C. 120%
D. 200% Correct answer C
The most likely cause of an intermittent hissing sound "like
water dripping on something hot" coming from a water
heater is:
A. an intermittent leak in the flue that seals once the tank
heats up
B. Condensation in the flue passage caused by drawing
water from the tank when the hot water has been depleted
C. Condensation in the flue passage caused by high
humidity in the combustion air supply to the water heater
D. Condensation in the flue passage caused by high
moisture content in the as supply Correct answer B
Why is there a low limit on a hot water tank which supplies
both space heating and domestic hot water?
A. To prevent rusting in the system
B. To prevent freeze up
C. To reduce oil consumption
D. To assure a constant supply of domestic hot water
Correct answer D
