NATE :Heat Pump Exam 2024 Questions with
100% Correct Answers
What is the purpose of the reversing valve on an air-to-air heat pump:
It changes the flow of the refrigerant, making the indoor coil the condenser during the winter months
On a reversing-valve solenoid, what is connected to the top tube:
the compressor discharge line
On a reversing-valve solenoid, what is connected to the bottom center tube:
the compressor suction line
What pressure difference must be between the low side and the high side of the heat pump system
for the reversing valve to operate properly:
75 psig
Where are the check valves located on an air-to-air heat pump:
on the outdoor coil and indoor coil
How are the check valves connected in a heat pump system:
in parallel with both metering devices+in series with one metering device and parallel with the other
A ball-type check valve must be installed:
vertically, with the seat on the bottom of the valve
When installing a ball-type check valve, what must be done to prevent warping:
A heat sink must be used when brazing it into the line
Where is the accumulator located on a heat pump system:
between the bottom center tube of the reversing valve and the compressor
When would you most likely find liquid in the vapor line on a heat pump:
during the heating mode after a defrost
What component must always be de-energized during the defrost cycle on a heat pump:
the outdoor fan
Why are the auxiliary strip heaters energized during the defrost cycle:
to increase supply-air temperature for comfort
What position must the reversing valve be in during the defrost cycle:
the cooling mode
When a heat pump switches into the defrost cycle, it must:
100% Correct Answers
What is the purpose of the reversing valve on an air-to-air heat pump:
It changes the flow of the refrigerant, making the indoor coil the condenser during the winter months
On a reversing-valve solenoid, what is connected to the top tube:
the compressor discharge line
On a reversing-valve solenoid, what is connected to the bottom center tube:
the compressor suction line
What pressure difference must be between the low side and the high side of the heat pump system
for the reversing valve to operate properly:
75 psig
Where are the check valves located on an air-to-air heat pump:
on the outdoor coil and indoor coil
How are the check valves connected in a heat pump system:
in parallel with both metering devices+in series with one metering device and parallel with the other
A ball-type check valve must be installed:
vertically, with the seat on the bottom of the valve
When installing a ball-type check valve, what must be done to prevent warping:
A heat sink must be used when brazing it into the line
Where is the accumulator located on a heat pump system:
between the bottom center tube of the reversing valve and the compressor
When would you most likely find liquid in the vapor line on a heat pump:
during the heating mode after a defrost
What component must always be de-energized during the defrost cycle on a heat pump:
the outdoor fan
Why are the auxiliary strip heaters energized during the defrost cycle:
to increase supply-air temperature for comfort
What position must the reversing valve be in during the defrost cycle:
the cooling mode
When a heat pump switches into the defrost cycle, it must:
