HVAC NATE HEAT PUMP TEST BANK 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◉ On a reversing-valve solenoid, what is connected to the top tube:
Answer: the compressor discharge line
◉ On a reversing-valve solenoid, what is connected to the bottom center
tube: Answer: 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:
Answer: 75 psig
◉ Where are the check valves located on an air-to-air heat pump:
Answer: on the outdoor coil and indoor coil
◉ How are the check valves connected in a heat pump system: Answer:
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: Answer: vertically, with the
seat on the bottom of the valve
, ◉ When installing a ball-type check valve, what must be done to prevent
warping: Answer: A heat sink must be used when brazing it into the line
◉ Where is the accumulator located on a heat pump system: Answer:
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: Answer: during the heating mode after a defrost
◉ What component must always be de-energized during the defrost
cycle on a heat pump: Answer: the outdoor fan
◉ Why are the auxiliary strip heaters energized during the defrost cycle:
Answer: to increase supply-air temperature for comfort
◉ What position must the reversing valve be in during the defrost cycle:
Answer: the cooling mode
◉ When a heat pump switches into the defrost cycle, it must: Answer:
remain in defrost until the outdoor coil has reached a predetermined
temperature
◉ A defrost termination thermostat is commonly located: Answer: on the
outdoor coil, and opens at 55° F
QUESTIONS WITH SOLUTIONS GRADED A+
◉ On a reversing-valve solenoid, what is connected to the top tube:
Answer: the compressor discharge line
◉ On a reversing-valve solenoid, what is connected to the bottom center
tube: Answer: 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:
Answer: 75 psig
◉ Where are the check valves located on an air-to-air heat pump:
Answer: on the outdoor coil and indoor coil
◉ How are the check valves connected in a heat pump system: Answer:
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: Answer: vertically, with the
seat on the bottom of the valve
, ◉ When installing a ball-type check valve, what must be done to prevent
warping: Answer: A heat sink must be used when brazing it into the line
◉ Where is the accumulator located on a heat pump system: Answer:
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: Answer: during the heating mode after a defrost
◉ What component must always be de-energized during the defrost
cycle on a heat pump: Answer: the outdoor fan
◉ Why are the auxiliary strip heaters energized during the defrost cycle:
Answer: to increase supply-air temperature for comfort
◉ What position must the reversing valve be in during the defrost cycle:
Answer: the cooling mode
◉ When a heat pump switches into the defrost cycle, it must: Answer:
remain in defrost until the outdoor coil has reached a predetermined
temperature
◉ A defrost termination thermostat is commonly located: Answer: on the
outdoor coil, and opens at 55° F
