HVAC Level 4 Technician Certification Exam Practice Questions
And Correct Answers (100% Solved) Latest Update 2026/2027 |
Graded A+ | Guaranteed Pass.
1. What is the primary purpose of a superheat measurement in a
refrigeration system?
a) To measure the system’s pressure
b) To prevent compressor damage
c) To check airflow
d) To determine the refrigerant type
Answer: b) To prevent compressor damage
Superheat ensures that only vapor enters the compressor, preventing
liquid refrigerant from causing damage.
2. Which type of expansion device provides variable metering based
on load conditions? a) Fixed orifice
b) Capillary tube
c) Thermostatic expansion valve (TXV)
d) Manual valve
Answer: c) Thermostatic expansion valve (TXV)
TXVs adjust refrigerant flow dynamically to maintain proper superheat
at the evaporator.
3. What is the effect of high indoor humidity on an HVAC system?
a) Reduces cooling efficiency
b) Increases heating efficiency
c) Has no effect
,d) Improves airflow
Answer: a) Reduces cooling efficiency
High humidity increases the latent cooling load, making the system work
harder to remove moisture.
4. Which type of refrigerant is classified as low GWP and low ODP?
a) R-22
b) R-410A
c) R-32
d) R-134a
Answer: c) R-32
R-32 has lower global warming potential and zero ozone depletion
potential compared to older refrigerants.
6. Which is the most accurate method to measure airflow in an HVAC
duct?
a) Pressure gauge
b) Thermometer
c) Anemometer
d) Hygrometer
Answer: c) Anemometer
An anemometer directly measures air velocity and, when combined with
duct cross-sectional area, calculates airflow.
7. What is the function of a heat recovery ventilator (HRV)?
a) Increase refrigerant efficiency
b) Recover heat from exhaust air
c) Dehumidify indoor air only
,d) Reduce static pressure
Answer: b) Recover heat from exhaust air
HRVs transfer heat between incoming fresh air and outgoing stale air,
improving energy efficiency.
8. Which electrical component controls the speed of a variable-speed
blower motor? a) Contactor
b) Transformer
c) Variable frequency drive (VFD)
d) Relay
Answer: c) Variable frequency drive (VFD)
VFDs adjust the motor speed by changing the frequency of the electrical
supply.
5. What component protects the compressor from liquid slugging? a)
Filter dryer
b) Suction accumulator
c) Condenser fan
d) TXV
Answer: b) Suction accumulator
The suction accumulator traps any liquid refrigerant to prevent it from
entering the compressor.
9. In a split-system air conditioner, the indoor unit contains which
components?
a) Compressor and condenser coil
, b) Condenser coil and expansion valve
c) Evaporator coil and blower
d) Condenser and metering device
Answer: c) Evaporator coil and blower
The indoor unit contains the evaporator, where heat is absorbed, and the
blower to circulate air.
12. Which refrigerant change is required when converting a system
from R-22 to R-410A?
a) No changes needed
b) New compressor oil and components rated for R-410A
c) Only change the metering device
d) Adjust the thermostat
Answer: b) New compressor oil and components rated for R-410A R-
410A operates at higher pressure and requires synthetic oil compatible
with the system.
13. What is the purpose of a condenser in a refrigeration system?
a) Evaporate refrigerant
b) Absorb heat from the indoor air
c) Reject heat to the outdoor air
d) Measure system pressure
Answer: c) Reject heat to the outdoor air
The condenser releases the heat absorbed from inside to the outside
environment.
14. Which tool is used to check for refrigerant leaks in a sealed
system?
a) Manometer
And Correct Answers (100% Solved) Latest Update 2026/2027 |
Graded A+ | Guaranteed Pass.
1. What is the primary purpose of a superheat measurement in a
refrigeration system?
a) To measure the system’s pressure
b) To prevent compressor damage
c) To check airflow
d) To determine the refrigerant type
Answer: b) To prevent compressor damage
Superheat ensures that only vapor enters the compressor, preventing
liquid refrigerant from causing damage.
2. Which type of expansion device provides variable metering based
on load conditions? a) Fixed orifice
b) Capillary tube
c) Thermostatic expansion valve (TXV)
d) Manual valve
Answer: c) Thermostatic expansion valve (TXV)
TXVs adjust refrigerant flow dynamically to maintain proper superheat
at the evaporator.
3. What is the effect of high indoor humidity on an HVAC system?
a) Reduces cooling efficiency
b) Increases heating efficiency
c) Has no effect
,d) Improves airflow
Answer: a) Reduces cooling efficiency
High humidity increases the latent cooling load, making the system work
harder to remove moisture.
4. Which type of refrigerant is classified as low GWP and low ODP?
a) R-22
b) R-410A
c) R-32
d) R-134a
Answer: c) R-32
R-32 has lower global warming potential and zero ozone depletion
potential compared to older refrigerants.
6. Which is the most accurate method to measure airflow in an HVAC
duct?
a) Pressure gauge
b) Thermometer
c) Anemometer
d) Hygrometer
Answer: c) Anemometer
An anemometer directly measures air velocity and, when combined with
duct cross-sectional area, calculates airflow.
7. What is the function of a heat recovery ventilator (HRV)?
a) Increase refrigerant efficiency
b) Recover heat from exhaust air
c) Dehumidify indoor air only
,d) Reduce static pressure
Answer: b) Recover heat from exhaust air
HRVs transfer heat between incoming fresh air and outgoing stale air,
improving energy efficiency.
8. Which electrical component controls the speed of a variable-speed
blower motor? a) Contactor
b) Transformer
c) Variable frequency drive (VFD)
d) Relay
Answer: c) Variable frequency drive (VFD)
VFDs adjust the motor speed by changing the frequency of the electrical
supply.
5. What component protects the compressor from liquid slugging? a)
Filter dryer
b) Suction accumulator
c) Condenser fan
d) TXV
Answer: b) Suction accumulator
The suction accumulator traps any liquid refrigerant to prevent it from
entering the compressor.
9. In a split-system air conditioner, the indoor unit contains which
components?
a) Compressor and condenser coil
, b) Condenser coil and expansion valve
c) Evaporator coil and blower
d) Condenser and metering device
Answer: c) Evaporator coil and blower
The indoor unit contains the evaporator, where heat is absorbed, and the
blower to circulate air.
12. Which refrigerant change is required when converting a system
from R-22 to R-410A?
a) No changes needed
b) New compressor oil and components rated for R-410A
c) Only change the metering device
d) Adjust the thermostat
Answer: b) New compressor oil and components rated for R-410A R-
410A operates at higher pressure and requires synthetic oil compatible
with the system.
13. What is the purpose of a condenser in a refrigeration system?
a) Evaporate refrigerant
b) Absorb heat from the indoor air
c) Reject heat to the outdoor air
d) Measure system pressure
Answer: c) Reject heat to the outdoor air
The condenser releases the heat absorbed from inside to the outside
environment.
14. Which tool is used to check for refrigerant leaks in a sealed
system?
a) Manometer
