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G2 EXAM PREPARATION VERSION 2 NEWEST
2025/2026 COMPLETE 300 QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW VERSION!!
What is a vapor barrier installed in the building envelope, and what is the minimum thickness - ANSWER-On the interior side of the insulation or at least no more than one third of the depth of the insulation from the interior
What is the outside circumference of a 4L-280 "v" drive belt - ANSWER- 28"
How would you measure humidity - ANSWER-Wet bulb and dry bulb
After the appliance has been checked and repaired, what is done prior to conversion - ANSWER-Combustion air and venting system must be re- sized for the new fuel
A furnace is found to be cycling on the high limit. The fan rotation, belt, filter and the clocked input is according to the rating plate. What is the most Lilly problem - ANSWER-return air volume is too low 1 / 4
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Vapour barriers should be installed on - ANSWER-The warm side of the insulation
A forced warm air furnace uses________ form of heat transfer to heat a home - ANSWER-Convective
Currently the most common type of building constructed is a - ANSWER-Platform
Main components of a gas fired refrigerator are - ANSWER-Generator, evaporator, absorber, condenser
The temp of the water returning from the heating loop in a combo system employer a water heater for domestic hot water and space heating must be - ANSWER-Lower than the minimum temperature required to activate the burner
A second stage regulator located outdoors shall be installed - ANSWER- Vertically with the vent at the bottom or facing down
If an a/c system is added to a heating system, it is recommended that - ANSWER-A larger motor pulley be installed 2 / 4
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To reduce heat loss, the most effective thing to do is - ANSWER-Seal air leaks
What hydronic control de-energizes the main burner if the operating control fails in the closed position - ANSWER-The high limit control
All relay contacts on a electrical schematic must be designated to - ANSWER-The same coil that operates them
Net stack temp is the glue gas temp - ANSWER-Minus the ambient temperature
If the belt on the blower motor is to tight the - ANSWER-motor current will increase
What will happen when the neutral pressure point for a conversion burner is improperly set - ANSWER-The burner efficiency will be affected
What is the main reason for a blown fuse - ANSWER-Excessive amperage
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For appliances with the same input, the same orfice used for a propane appliance should be - ANSWER-Smaller than the orfice used for natural gas
A therm-o-disc operating the door locking mechanism in a self cleaning oven locks at - ANSWER-650F (340c)
The stacking effect in a water heater is usually cause by - ANSWER-Short draws of water from the heater
Millivolt wiring should be isolated from Line Voltage Wiring because - ANSWER-The Line Voltage will induce a Voltage into the Millivolt Wiring
If a natural gas service regulator appears to be incorrectly adjusted - ANSWER-Contact the gas supplier
What is required to determine the size of a circulator pump to be used in a combo system employing a water heater - ANSWER-The required flow rate and the head pressure in the complete heating loop
As the temperature difference between the outdoor and indoor temp increase the stack effect - ANSWER-Causes an increase in air pressure in the upper levels of the building
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