GAS FITTER 2 PRACTICE TEST EXAM
QUESTIONS WITH CORRECT ANSWERS
What diameter and length of a dirt pocket is required when a drop line is 3-inch
diameter?
A. 3 inch diameter by 3 inches long
B. 1 inch diameter by 3 inches long
C. 3/4 inch diameter by 3 inches long
D. 2 inch diameter by 3 inches long - Answer-D
What type of room heater maybe installed in a bathroom?
A. Natural draft
B. Direct fired
C. Forced draft
D. Direct vent - Answer-D
What safety control protects a steam boiler if the condensate pump fails to return water
to the boiler?
A. High pressure limit control
B. Low pressure limit control
C. Flame safeguard control
D. Low water cut off - Answer-D
The relief valve for a residential low-pressure hot water boiler system should be?
A. 14.7 psia
B. 15 psia
C. 30 psig
D. 30 psia - Answer-C
A backflow prevent used in a boiler system should be located in the:
A. Over flow line connected to the drain
B. Return line close to the boiler
C. 1/4" line connecting the boiler and cushion tank
D. Make up water line to the system - Answer-B
Automatic chlorinators must be installed:
A. upstream of the heater
B. downstream of the heater
C. upstream of the filter
D. downstream of the filter - Answer-B
On seasonal start up, a pool heater should run:
A. intermittently
B. continuously for 24 hours
,C. continuously until the thermostat is satisfied
D. one hour on and one hour off until the thermostat is satisfied - Answer-C
Before lighting a burner in a steam boiler, ensure that:
A. there is water in the boiler
B. the temperature controller is set properly
C. the main burner test firing valve is turned on
D. the safety valves are open - Answer-A
The recommended water temperature setting from a mixing valve to the domestic water
system in combination heating systems that employ oil-fired water heaters for heating
potable water and for space heating is:
A. 43°C (110°F)
B. 49°C to 54°C (120°F to 130°F)
C. 60°C to 66°C (140°F to 150°F)
D. 83°C (180°F) - Answer-B
An inverted sensor (measures water level) can be found operating what type of
appliance?
A. Hot water boiler
B. Steam water boiler
C. Domestic hot water storage tank
D. Domestic potable hot water tank - Answer-D
A backflow prevent used in a hydronic heating system is used to:
A. Keep hot water from entering the cold water system
B. Hold the pressure on the system during a temporary shutdown to prevent the entry of
air
C. Prevent the heating water from circulating the wrong way in the system
D. Keep non-combustible water from entering the drinking water system - Answer-D
A low water cut off device on an automatically fired hot water heating boiler rated at
350,000 Btuh (102 kW) is:
A. Not required if a limit control is installed
B. Not required if it is installed in the industrial application
C. Required when any portion of the circulating system is located below the boiler
D. Required only in commercial applications - Answer-C
A pressure reducing valve
A. Relieves system pressure in excess of the set pressure
B. Reduces the city main pressure to a safe working pressure
C. Reduces the working pressure to the city main pressure
D. Prevents hot water gravity circulation - Answer-B
The maximum operating pressure of a low pressure steam boiler is
A. 5 psig (35kPa)
,B. 15 psig (100 kPa)
C. 100 psig (690 kPa)
D. 150 psig (1035 kPa) - Answer-B
A scotch marine boiler is what type of boiler?
A. Two pass boiler
B. Copper tube boiler
C. Fire tube boiler
D. Four pass water tube boiler - Answer-C
A fire tube boiler has:
A. Water outside the tube and flue gases outside
B. Water inside the tubes and flue gasses outside
C. Water inside the tubes and water outside
D. Water outside the tubes and flue gases inside - Answer-D
Why is a pressure relief valve installed on a pool heater system?
A. To maintain the pool water level
B. To prevent over pressurizing the filter
C. To prevent damage to the system
D. To relieve excess water pressure caused by solar gun - Answer-C
When does an electrically operated automatic vent damper on a mid-efficiency furnace
open?
A. Before the ignition cycle
B. When the furnace is hot
C. At the same time as the gas comes on
D. When the main switch is turned on - Answer-A
What is the minimum distance the vent of a Category 4 furnace with an input under
100,000 Btuh can terminate from a combustion air inlet of any other appliance?
A. 12"
B. 36"
C. 60"
D. 120" - Answer-A
If an air conditioning system is added to a heating system, it is recommended that:
A. A smaller blower pulley be installed
B. A larger blower pulley be installed
C. A larger motor pulley be installed
D. A smaller motor pulley be installed - Answer-C
If an appliance is less than 83% efficient and non-positive it would be considered a?
A. Category II
B. Category I
C. Category IV
, D. Category III - Answer-B
When is it premissible to vent a Category IV furnace into the sam chimney or vent as a
water heater?
A. it is always allowed
B. it is never allowed
C. it is allowed only when a "T" or "Y" fitting is used
D. it is allowed only when "B" vent is used - Answer-B
When can combination heating systems employing a waterheater be attached to
baseboards or radiators that were previously used for boiler heating - Answer-B
The minimum allowable distance to be maintained from a 50,000 Btuh water heater flue
outlet to grade level is:
A. 6" (150mm)
B. 12" (300mm)
C. 18" (450mm)
D. 24" (600mm) - Answer-B
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 - 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 - 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 - 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
QUESTIONS WITH CORRECT ANSWERS
What diameter and length of a dirt pocket is required when a drop line is 3-inch
diameter?
A. 3 inch diameter by 3 inches long
B. 1 inch diameter by 3 inches long
C. 3/4 inch diameter by 3 inches long
D. 2 inch diameter by 3 inches long - Answer-D
What type of room heater maybe installed in a bathroom?
A. Natural draft
B. Direct fired
C. Forced draft
D. Direct vent - Answer-D
What safety control protects a steam boiler if the condensate pump fails to return water
to the boiler?
A. High pressure limit control
B. Low pressure limit control
C. Flame safeguard control
D. Low water cut off - Answer-D
The relief valve for a residential low-pressure hot water boiler system should be?
A. 14.7 psia
B. 15 psia
C. 30 psig
D. 30 psia - Answer-C
A backflow prevent used in a boiler system should be located in the:
A. Over flow line connected to the drain
B. Return line close to the boiler
C. 1/4" line connecting the boiler and cushion tank
D. Make up water line to the system - Answer-B
Automatic chlorinators must be installed:
A. upstream of the heater
B. downstream of the heater
C. upstream of the filter
D. downstream of the filter - Answer-B
On seasonal start up, a pool heater should run:
A. intermittently
B. continuously for 24 hours
,C. continuously until the thermostat is satisfied
D. one hour on and one hour off until the thermostat is satisfied - Answer-C
Before lighting a burner in a steam boiler, ensure that:
A. there is water in the boiler
B. the temperature controller is set properly
C. the main burner test firing valve is turned on
D. the safety valves are open - Answer-A
The recommended water temperature setting from a mixing valve to the domestic water
system in combination heating systems that employ oil-fired water heaters for heating
potable water and for space heating is:
A. 43°C (110°F)
B. 49°C to 54°C (120°F to 130°F)
C. 60°C to 66°C (140°F to 150°F)
D. 83°C (180°F) - Answer-B
An inverted sensor (measures water level) can be found operating what type of
appliance?
A. Hot water boiler
B. Steam water boiler
C. Domestic hot water storage tank
D. Domestic potable hot water tank - Answer-D
A backflow prevent used in a hydronic heating system is used to:
A. Keep hot water from entering the cold water system
B. Hold the pressure on the system during a temporary shutdown to prevent the entry of
air
C. Prevent the heating water from circulating the wrong way in the system
D. Keep non-combustible water from entering the drinking water system - Answer-D
A low water cut off device on an automatically fired hot water heating boiler rated at
350,000 Btuh (102 kW) is:
A. Not required if a limit control is installed
B. Not required if it is installed in the industrial application
C. Required when any portion of the circulating system is located below the boiler
D. Required only in commercial applications - Answer-C
A pressure reducing valve
A. Relieves system pressure in excess of the set pressure
B. Reduces the city main pressure to a safe working pressure
C. Reduces the working pressure to the city main pressure
D. Prevents hot water gravity circulation - Answer-B
The maximum operating pressure of a low pressure steam boiler is
A. 5 psig (35kPa)
,B. 15 psig (100 kPa)
C. 100 psig (690 kPa)
D. 150 psig (1035 kPa) - Answer-B
A scotch marine boiler is what type of boiler?
A. Two pass boiler
B. Copper tube boiler
C. Fire tube boiler
D. Four pass water tube boiler - Answer-C
A fire tube boiler has:
A. Water outside the tube and flue gases outside
B. Water inside the tubes and flue gasses outside
C. Water inside the tubes and water outside
D. Water outside the tubes and flue gases inside - Answer-D
Why is a pressure relief valve installed on a pool heater system?
A. To maintain the pool water level
B. To prevent over pressurizing the filter
C. To prevent damage to the system
D. To relieve excess water pressure caused by solar gun - Answer-C
When does an electrically operated automatic vent damper on a mid-efficiency furnace
open?
A. Before the ignition cycle
B. When the furnace is hot
C. At the same time as the gas comes on
D. When the main switch is turned on - Answer-A
What is the minimum distance the vent of a Category 4 furnace with an input under
100,000 Btuh can terminate from a combustion air inlet of any other appliance?
A. 12"
B. 36"
C. 60"
D. 120" - Answer-A
If an air conditioning system is added to a heating system, it is recommended that:
A. A smaller blower pulley be installed
B. A larger blower pulley be installed
C. A larger motor pulley be installed
D. A smaller motor pulley be installed - Answer-C
If an appliance is less than 83% efficient and non-positive it would be considered a?
A. Category II
B. Category I
C. Category IV
, D. Category III - Answer-B
When is it premissible to vent a Category IV furnace into the sam chimney or vent as a
water heater?
A. it is always allowed
B. it is never allowed
C. it is allowed only when a "T" or "Y" fitting is used
D. it is allowed only when "B" vent is used - Answer-B
When can combination heating systems employing a waterheater be attached to
baseboards or radiators that were previously used for boiler heating - Answer-B
The minimum allowable distance to be maintained from a 50,000 Btuh water heater flue
outlet to grade level is:
A. 6" (150mm)
B. 12" (300mm)
C. 18" (450mm)
D. 24" (600mm) - Answer-B
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 - 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 - 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 - 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
