NATE Heat Pump Service Exam Questions and Correct Answers

NATE HEAT PUMP SERVICE EXAM QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2027 |INSTANT DOWNLAOD PDF
1. What is the primary function of a heat pump in heating
mode?
A. Remove heat from indoors and reject it outdoors
B. Transfer heat from outdoors to indoors
C. Convert electrical energy directly into heat
D. Circulate only indoor air
Correct Answer: B. Transfer heat from outdoors to indoors
Rationale: In heating mode, a heat pump absorbs available
heat from the outdoor environment and transfers it indoors.
2. Which component reverses refrigerant flow between
heating and cooling modes?
A. Thermostatic expansion valve
B. Accumulator
C. Reversing valve
D. Filter-drier
Correct Answer: C. Reversing valve
Rationale: The reversing valve changes the direction of
refrigerant flow so the system can operate in either heating or
cooling mode.
3. In cooling mode, the indoor coil normally functions as the:
A. Condenser
B. Evaporator

,C. Receiver
D. Accumulator
Correct Answer: B. Evaporator
Rationale: The indoor coil absorbs heat from indoor air as
refrigerant evaporates.
4. In heating mode, the indoor coil normally functions as the:
A. Evaporator
B. Condenser
C. Receiver
D. Suction accumulator
Correct Answer: B. Condenser
Rationale: In heating mode, hot refrigerant vapor releases heat
through the indoor coil and condenses.
5. Which component compresses low-pressure refrigerant
vapor?
A. Compressor
B. Condenser
C. Expansion valve
D. Receiver
Correct Answer: A. Compressor
Rationale: The compressor raises the pressure and
temperature of the refrigerant vapor.
6. What is the purpose of the outdoor coil in heating mode?
A. Reject heat to outdoor air
B. Absorb heat from outdoor air

,C. Store liquid refrigerant
D. Reduce compressor discharge pressure
Correct Answer: B. Absorb heat from outdoor air
Rationale: The outdoor coil operates as the evaporator during
heating and absorbs heat from the outdoor environment.
7. What happens to refrigerant pressure across a typical
metering device?
A. It increases substantially
B. It remains constant
C. It decreases
D. It becomes atmospheric
Correct Answer: C. It decreases
Rationale: The metering device creates a pressure drop that
allows the refrigerant to evaporate at a lower temperature.
8. Which measurement is most useful for evaluating
evaporator refrigerant feed?
A. Superheat
B. Voltage only
C. Wire resistance only
D. Oil level only
Correct Answer: A. Superheat
Rationale: Superheat helps determine whether the evaporator
is receiving an appropriate amount of refrigerant.
9. What does subcooling measure?
A. Temperature of vapor above saturation temperature

, B. Temperature of liquid below saturation temperature
C. Compressor amperage
D. Airflow through the blower
Correct Answer: B. Temperature of liquid below saturation
temperature
Rationale: Subcooling is the difference between the saturation
temperature and actual liquid refrigerant temperature.
10. Which component protects a compressor from liquid
refrigerant entering the suction line?
A. Receiver
B. Suction accumulator
C. Condenser
D. Sight glass
Correct Answer: B. Suction accumulator
Rationale: A suction accumulator can temporarily collect liquid
refrigerant and help prevent liquid from reaching the
compressor.
11. What is compressor liquid slugging?
A. Excessive air velocity
B. Liquid refrigerant entering the compressor
C. Low condenser airflow
D. Refrigerant leakage from the condenser
Correct Answer: B. Liquid refrigerant entering the compressor
Rationale: Compressors are designed primarily to compress