HVAC Heating test Questions With
Complete Verified Solutions.
On a central gas furnace, which of the following conditions would cause the high limit control to open
circuit ? - Answer Fan contol is open
After replacing the compressor in a heat pump during the heating season, a technician must charge the
system to the proper lvl. Which is the most accurate method ? - Answer Weigh in the exact charge
A situation in which the flame on a gas furnace continually rolls out could be caused by - Answer A
plugged heater exchange
On heat pumps using a liquid line temperature sensing device for the terminating defrost cycles, which
causes device to terminate defrost - Answer Increase in the temperate of the liquid line
In a duct system, where should vibration eliminators be placed ? - Answer Between air handler and first
duct
A correct statement regarding the fan/limit controller is that it senses the: - Answer Supply air
temperature in the furnace
A correct statement regarding suction line filter driers is that they should be used when: - Answer
Replacing a compressor after a burnout
The component that is installed on the low since to prevent liquid from entering the compressor is called
an : - Answer Accumulator
The reason many residents are not equipped to take in fresh air through duct system is because : -
Answer Infiltration is used to meet the need for fresh air
, In a natural draft gas- fired furnace, most probable cause of the flame lifting off the burner is: - Answer
Too much gas pressure
For proper burner operation, the manifold pressure on atmospheric draft natural gas-fires furnaces
should be: - Answer 3-4 inches of water
The purpose of sequencer replays in an electric warm-air heating system is to: - Answer Prevent all
elements from being energized at same times
An increase in the latent heat load across the evaporator will cause which of the following changes: -
Answer An increase in evaporator and condenser pressure
The normal indoor airflow through a heat pump or air conditioner should be approximately - Answer
400 cfm/ton
With an oil gun burner, atomized oil is ignited by an: - Answer Electrics arc between electrodes
To check if a fixed resistance crankcase heater is operating with power applied, you would normally use -
Answer An ammeter
Which of the following is the most probable cause of a high discharge pressures in a cooling system ? -
Answer Dirty condenser coil
Commonly specified manufacturers requirements for the venting of 90+ high efficiency furnaces are
sized for vent, number of elbows, venting materials? And: - Answer Length of vent
The most important advantage of using brazing alloys with a higher silver content is that ? - Answer
The joint is stronger
On split system air conditioner, increasing the air flow through an evaporator : - Answer Will cause frost
to build up on coil
Complete Verified Solutions.
On a central gas furnace, which of the following conditions would cause the high limit control to open
circuit ? - Answer Fan contol is open
After replacing the compressor in a heat pump during the heating season, a technician must charge the
system to the proper lvl. Which is the most accurate method ? - Answer Weigh in the exact charge
A situation in which the flame on a gas furnace continually rolls out could be caused by - Answer A
plugged heater exchange
On heat pumps using a liquid line temperature sensing device for the terminating defrost cycles, which
causes device to terminate defrost - Answer Increase in the temperate of the liquid line
In a duct system, where should vibration eliminators be placed ? - Answer Between air handler and first
duct
A correct statement regarding the fan/limit controller is that it senses the: - Answer Supply air
temperature in the furnace
A correct statement regarding suction line filter driers is that they should be used when: - Answer
Replacing a compressor after a burnout
The component that is installed on the low since to prevent liquid from entering the compressor is called
an : - Answer Accumulator
The reason many residents are not equipped to take in fresh air through duct system is because : -
Answer Infiltration is used to meet the need for fresh air
, In a natural draft gas- fired furnace, most probable cause of the flame lifting off the burner is: - Answer
Too much gas pressure
For proper burner operation, the manifold pressure on atmospheric draft natural gas-fires furnaces
should be: - Answer 3-4 inches of water
The purpose of sequencer replays in an electric warm-air heating system is to: - Answer Prevent all
elements from being energized at same times
An increase in the latent heat load across the evaporator will cause which of the following changes: -
Answer An increase in evaporator and condenser pressure
The normal indoor airflow through a heat pump or air conditioner should be approximately - Answer
400 cfm/ton
With an oil gun burner, atomized oil is ignited by an: - Answer Electrics arc between electrodes
To check if a fixed resistance crankcase heater is operating with power applied, you would normally use -
Answer An ammeter
Which of the following is the most probable cause of a high discharge pressures in a cooling system ? -
Answer Dirty condenser coil
Commonly specified manufacturers requirements for the venting of 90+ high efficiency furnaces are
sized for vent, number of elbows, venting materials? And: - Answer Length of vent
The most important advantage of using brazing alloys with a higher silver content is that ? - Answer
The joint is stronger
On split system air conditioner, increasing the air flow through an evaporator : - Answer Will cause frost
to build up on coil
