Industry Competency Exam (ICE) Light
Commercial HVAC Practice Exam
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which type of refrigerant is most commonly used in light commercial
HVAC systems today?
A. R-22
B. R-410A
C. R-134a
D. R-12
R-410A is widely used in modern light commercial HVAC systems due
to its efficiency and lower ozone depletion potential compared to R-
22.
2. What is the purpose of a TXV (Thermostatic Expansion Valve) in a
refrigeration system?
, A. Increase compressor efficiency
B. Regulate the flow of refrigerant into the evaporator
C. Reduce condenser pressure
D. Heat the air in winter
A TXV controls refrigerant flow to the evaporator to ensure proper
superheat and efficient heat transfer.
3. In a direct expansion (DX) cooling system, the evaporator is located:
A. After the condenser
B. Inside the air handler
C. In the compressor
D. Outside the building
The DX evaporator is inside the air handler or indoor unit, where it
absorbs heat from the conditioned air.
4. What is the primary purpose of a condenser in an HVAC system?
A. Cool the air
B. Increase refrigerant pressure
C. Reject heat from the refrigerant to the environment
D. Filter indoor air
The condenser removes heat from the refrigerant, allowing it to
condense from a gas to a liquid.
5. Which type of compressor is commonly used in light commercial
rooftop units?
A. Scroll
, B. Reciprocating
C. Screw
D. Scroll
Scroll compressors are preferred for light commercial systems due to
their reliability, efficiency, and low vibration.
6. What is the typical pressure range for a medium-temperature R-410A
system evaporator?
A. 10-50 psi
B. 60-100 psi
C. 110-145 psi
D. 200-250 psi
R-410A operates at higher pressures than older refrigerants;
medium-temperature evaporators usually run around 110-145 psi.
7. What is superheat in a refrigeration system?
A. The temperature of refrigerant in the condenser
B. The heat added to the compressor
C. The temperature of refrigerant vapor above its saturation
temperature
D. The difference between ambient air and return air
Superheat is measured at the evaporator outlet to ensure no liquid
refrigerant enters the compressor.
8. Which safety device protects the compressor from overpressure in the
discharge line?
, A. Low-pressure switch
B. High-pressure switch
C. TXV
D. Expansion valve
A high-pressure switch shuts off the compressor if discharge pressure
exceeds safe limits, preventing damage.
9. Which airflow problem can cause icing on the evaporator coil?
A. Low refrigerant charge
B. Restricted airflow
C. Dirty condenser coil
D. High outdoor temperature
Restricted airflow reduces heat transfer at the evaporator, causing
the coil to drop below freezing and ice to form.
10. In light commercial HVAC, what is the main function of a
economizer?
A. Reduce refrigerant pressure
B. Use outside air for free cooling when conditions allow
C. Increase indoor humidity
D. Protect compressors
Economizers reduce energy costs by using cool outside air to assist or
replace mechanical cooling.
11. What is the typical efficiency rating used for light commercial
rooftop units?
Commercial HVAC Practice Exam
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which type of refrigerant is most commonly used in light commercial
HVAC systems today?
A. R-22
B. R-410A
C. R-134a
D. R-12
R-410A is widely used in modern light commercial HVAC systems due
to its efficiency and lower ozone depletion potential compared to R-
22.
2. What is the purpose of a TXV (Thermostatic Expansion Valve) in a
refrigeration system?
, A. Increase compressor efficiency
B. Regulate the flow of refrigerant into the evaporator
C. Reduce condenser pressure
D. Heat the air in winter
A TXV controls refrigerant flow to the evaporator to ensure proper
superheat and efficient heat transfer.
3. In a direct expansion (DX) cooling system, the evaporator is located:
A. After the condenser
B. Inside the air handler
C. In the compressor
D. Outside the building
The DX evaporator is inside the air handler or indoor unit, where it
absorbs heat from the conditioned air.
4. What is the primary purpose of a condenser in an HVAC system?
A. Cool the air
B. Increase refrigerant pressure
C. Reject heat from the refrigerant to the environment
D. Filter indoor air
The condenser removes heat from the refrigerant, allowing it to
condense from a gas to a liquid.
5. Which type of compressor is commonly used in light commercial
rooftop units?
A. Scroll
, B. Reciprocating
C. Screw
D. Scroll
Scroll compressors are preferred for light commercial systems due to
their reliability, efficiency, and low vibration.
6. What is the typical pressure range for a medium-temperature R-410A
system evaporator?
A. 10-50 psi
B. 60-100 psi
C. 110-145 psi
D. 200-250 psi
R-410A operates at higher pressures than older refrigerants;
medium-temperature evaporators usually run around 110-145 psi.
7. What is superheat in a refrigeration system?
A. The temperature of refrigerant in the condenser
B. The heat added to the compressor
C. The temperature of refrigerant vapor above its saturation
temperature
D. The difference between ambient air and return air
Superheat is measured at the evaporator outlet to ensure no liquid
refrigerant enters the compressor.
8. Which safety device protects the compressor from overpressure in the
discharge line?
, A. Low-pressure switch
B. High-pressure switch
C. TXV
D. Expansion valve
A high-pressure switch shuts off the compressor if discharge pressure
exceeds safe limits, preventing damage.
9. Which airflow problem can cause icing on the evaporator coil?
A. Low refrigerant charge
B. Restricted airflow
C. Dirty condenser coil
D. High outdoor temperature
Restricted airflow reduces heat transfer at the evaporator, causing
the coil to drop below freezing and ice to form.
10. In light commercial HVAC, what is the main function of a
economizer?
A. Reduce refrigerant pressure
B. Use outside air for free cooling when conditions allow
C. Increase indoor humidity
D. Protect compressors
Economizers reduce energy costs by using cool outside air to assist or
replace mechanical cooling.
11. What is the typical efficiency rating used for light commercial
rooftop units?
