G2 gas fitter exam prep Questions and
Answers 100% Solved
Which of the following flame detectors generates sufficient electricity to operate a main gas
valve and an operating/limit control circuit? ⬛
✓Correct Ans-thermopile
"Ignition spark response test" must be conducted on all installations that utilize what type of
detection system? ⬛✓Correct Ans-ultraviolet
What is the "minimum" flame rod to ground in area needed to operate a flame
rod detection system? ⬛
✓Correct Ans-ground fin area 4 times larger than the flame rod area
Identify the statement that bestdescribes flame rectification. ⬛
✓Correct Ans-the flame conducts
electrons better from the flame-rod to ground than from ground to flame rod causing an
average DC micro-amp signal
Draft that is caused by the pressure difference of hot gases rising in a chimney is called by:
✓Correct Ans-natural thermal draft
⬛
a high intensity surface combustion infrared heater requires: ⬛
✓Correct Ans-no vent
spillage of flue gases at the appliance draft diverter is an indication of: ⬛
✓Correct Ans-a
restriction in the venting systems
a draft hood will: ⬛
✓Correct Ans-prevent a downdraft from entering the appliance
insufficient natural draft can usually be corrected by: ⬛
✓Correct Ans-increasing the height of
the chimney
,A vent system that can only be used with an appliance that the vent system has been tested and
approved with is called a(n): ⬛
✓Correct Ans-special venting system
most underfired storage water heater temperature controls utilize ⬛
✓Correct Ans-rod and tube
sensors
a resistance temperature detector senses changes in temperature by: ⬛
✓Correct Ans-the
increase in resistance of a wire as temperatures increase
pressuretrols respond to changes in ⬛
✓Correct Ans-water or steam pressure
Aquastats respond to changes in ⬛
✓Correct Ans-water temperature
differential pressure switches sense: ⬛
✓Correct Ans-positive and negative pressure
simultaneously
what is the purpose of a low water cut-off device found on fas fired boilers? ⬛
✓Correct Ans-to
shut off the burner in the event of an unsafe water level in the boiler
If upon reactivation of an appliance a G-3 technician notices flame roll-out, the technician is
required to: ⬛
✓Correct Ans-turn off gas supply and call a qualified technician to repair the
problem
from the following list, what is the most important action to take before lighting a gas burner on
a boiler: ⬛
✓Correct Ans-ensure there is water in the boiler
the law of electrical charges is ⬛
✓Correct Ans-Like charges repel and opposite charges attract
, electrical current in a wire may cause ⬛
✓Correct Ans-friction and therefore heat in the wire, the
opposite electrical charge to be induced in another material, a magnetic field around the wire
electromotive force is another term for ⬛
✓Correct Ans-voltage
The voltage reading across an open switch of an energized electrical circuit should be:
✓Correct Ans-applied voltage
⬛
an ampere is a unit of measurement of: ⬛
✓Correct Ans-electrical current
Electrical current is measured in ⬛
✓Correct Ans-Amperes
electrical potential is measured in ⬛
✓Correct Ans-Volts
A DC voltage measurement is being taken when the needle on the analog meter moves below
zero on the scale. This indicates that the: ⬛
✓Correct Ans-test leads are reversed
"VA" rating on a transformer means ⬛
✓Correct Ans-the available power to the secondary unit
How many inches water column equal one psig pressure ⬛
✓Correct Ans-28"
How many pascals equal one psig pressure ⬛
✓Correct Ans-6895
the odorant added to natural gas for detection purposes is ⬛
✓Correct Ans-mercaptan
what is the approximate ignition temperature of natural gas ⬛
✓Correct Ans-1200*F(649*C)
the specific gravity of natural gas is ⬛
✓Correct Ans-0.6
Answers 100% Solved
Which of the following flame detectors generates sufficient electricity to operate a main gas
valve and an operating/limit control circuit? ⬛
✓Correct Ans-thermopile
"Ignition spark response test" must be conducted on all installations that utilize what type of
detection system? ⬛✓Correct Ans-ultraviolet
What is the "minimum" flame rod to ground in area needed to operate a flame
rod detection system? ⬛
✓Correct Ans-ground fin area 4 times larger than the flame rod area
Identify the statement that bestdescribes flame rectification. ⬛
✓Correct Ans-the flame conducts
electrons better from the flame-rod to ground than from ground to flame rod causing an
average DC micro-amp signal
Draft that is caused by the pressure difference of hot gases rising in a chimney is called by:
✓Correct Ans-natural thermal draft
⬛
a high intensity surface combustion infrared heater requires: ⬛
✓Correct Ans-no vent
spillage of flue gases at the appliance draft diverter is an indication of: ⬛
✓Correct Ans-a
restriction in the venting systems
a draft hood will: ⬛
✓Correct Ans-prevent a downdraft from entering the appliance
insufficient natural draft can usually be corrected by: ⬛
✓Correct Ans-increasing the height of
the chimney
,A vent system that can only be used with an appliance that the vent system has been tested and
approved with is called a(n): ⬛
✓Correct Ans-special venting system
most underfired storage water heater temperature controls utilize ⬛
✓Correct Ans-rod and tube
sensors
a resistance temperature detector senses changes in temperature by: ⬛
✓Correct Ans-the
increase in resistance of a wire as temperatures increase
pressuretrols respond to changes in ⬛
✓Correct Ans-water or steam pressure
Aquastats respond to changes in ⬛
✓Correct Ans-water temperature
differential pressure switches sense: ⬛
✓Correct Ans-positive and negative pressure
simultaneously
what is the purpose of a low water cut-off device found on fas fired boilers? ⬛
✓Correct Ans-to
shut off the burner in the event of an unsafe water level in the boiler
If upon reactivation of an appliance a G-3 technician notices flame roll-out, the technician is
required to: ⬛
✓Correct Ans-turn off gas supply and call a qualified technician to repair the
problem
from the following list, what is the most important action to take before lighting a gas burner on
a boiler: ⬛
✓Correct Ans-ensure there is water in the boiler
the law of electrical charges is ⬛
✓Correct Ans-Like charges repel and opposite charges attract
, electrical current in a wire may cause ⬛
✓Correct Ans-friction and therefore heat in the wire, the
opposite electrical charge to be induced in another material, a magnetic field around the wire
electromotive force is another term for ⬛
✓Correct Ans-voltage
The voltage reading across an open switch of an energized electrical circuit should be:
✓Correct Ans-applied voltage
⬛
an ampere is a unit of measurement of: ⬛
✓Correct Ans-electrical current
Electrical current is measured in ⬛
✓Correct Ans-Amperes
electrical potential is measured in ⬛
✓Correct Ans-Volts
A DC voltage measurement is being taken when the needle on the analog meter moves below
zero on the scale. This indicates that the: ⬛
✓Correct Ans-test leads are reversed
"VA" rating on a transformer means ⬛
✓Correct Ans-the available power to the secondary unit
How many inches water column equal one psig pressure ⬛
✓Correct Ans-28"
How many pascals equal one psig pressure ⬛
✓Correct Ans-6895
the odorant added to natural gas for detection purposes is ⬛
✓Correct Ans-mercaptan
what is the approximate ignition temperature of natural gas ⬛
✓Correct Ans-1200*F(649*C)
the specific gravity of natural gas is ⬛
✓Correct Ans-0.6
