USVI HVAC/R Technician Licensing Exam 2026 – 190 Practice
Questions with Answers & Detailed Rationales, Heating and Cooling
Systems, Refrigeration, Electrical Controls, HVAC Installation,
System Diagnostics, Troubleshooting, Preventive Maintenance,
Safety Standards & Licensing Exam Preparation
1. Heat always flows from:
A. Cold to hot
B. Hot to cold
C. Equal to equal
D. Random direction
Correct Answer: B
Heat spontaneously moves from higher to lower temperature.
2. A ton of refrigeration equals:
A. 6,000 BTU/hr
B. 12,000 BTU/hr
C. 18,000 BTU/hr
D. 24,000 BTU/hr
Correct Answer: B
One ton = 12,000 BTU/hr heat removal.
3. Superheat is measured as:
A. Liquid temp minus saturation
B. Suction temp minus saturation
C. Discharge temp minus ambient
D. Condenser temp minus outdoor
,Correct Answer: B
Superheat confirms vapor leaving evaporator.
4. Subcooling measures:
A. Vapor above saturation
B. Liquid below saturation
C. Compressor oil temp
D. Airflow across coil
Correct Answer: B
Subcooling verifies liquid seal at condenser.
5. A vacuum rising after isolation indicates:
A. Proper evacuation
B. Moisture or leak
C. Overcharge
D. Undersized pump
Correct Answer: B
Rising microns reveal moisture or leak.
6. Standard airflow per ton is:
A. 200 CFM
B. 300 CFM
C. 400 CFM
D. 500 CFM
Correct Answer: C
400 CFM/ton is nominal design airflow.
,7. High head pressure with high subcooling suggests:
A. Undercharge
B. Overcharge
C. Low airflow
D. Bad compressor
Correct Answer: B
Excess refrigerant raises head and subcooling.
8. A start capacitor provides:
A. Continuous torque
B. Starting torque
C. Voltage regulation
D. Phase balance
Correct Answer: B
Start capacitors boost motor starting torque.
9. Ohm's Law is:
A. V = I/R
B. V = I × R
C. R = V × I
D. I = V × R
Correct Answer: B
Voltage equals current times resistance.
10. A clamp meter measures:
A. Voltage
B. Current
C. Resistance
, D. Capacitance
Correct Answer: B
Clamp meters read current inductively.
11. A pressure relief valve protects against:
A. Low charge
B. Excess pressure
C. Voltage spikes
D. Ice buildup
Correct Answer: B
It vents at unsafe pressure limits.
12. An economizer saves energy by:
A. Boosting compressor
B. Using outdoor air
C. Heating refrigerant
D. Increasing charge
Correct Answer: B
Free cooling uses cool outdoor air.
13. A heat pump reverses flow using a:
A. Contactor
B. Reversing valve
C. Relay
D. Thermostat
Correct Answer: B
The reversing valve swaps coil functions.
Questions with Answers & Detailed Rationales, Heating and Cooling
Systems, Refrigeration, Electrical Controls, HVAC Installation,
System Diagnostics, Troubleshooting, Preventive Maintenance,
Safety Standards & Licensing Exam Preparation
1. Heat always flows from:
A. Cold to hot
B. Hot to cold
C. Equal to equal
D. Random direction
Correct Answer: B
Heat spontaneously moves from higher to lower temperature.
2. A ton of refrigeration equals:
A. 6,000 BTU/hr
B. 12,000 BTU/hr
C. 18,000 BTU/hr
D. 24,000 BTU/hr
Correct Answer: B
One ton = 12,000 BTU/hr heat removal.
3. Superheat is measured as:
A. Liquid temp minus saturation
B. Suction temp minus saturation
C. Discharge temp minus ambient
D. Condenser temp minus outdoor
,Correct Answer: B
Superheat confirms vapor leaving evaporator.
4. Subcooling measures:
A. Vapor above saturation
B. Liquid below saturation
C. Compressor oil temp
D. Airflow across coil
Correct Answer: B
Subcooling verifies liquid seal at condenser.
5. A vacuum rising after isolation indicates:
A. Proper evacuation
B. Moisture or leak
C. Overcharge
D. Undersized pump
Correct Answer: B
Rising microns reveal moisture or leak.
6. Standard airflow per ton is:
A. 200 CFM
B. 300 CFM
C. 400 CFM
D. 500 CFM
Correct Answer: C
400 CFM/ton is nominal design airflow.
,7. High head pressure with high subcooling suggests:
A. Undercharge
B. Overcharge
C. Low airflow
D. Bad compressor
Correct Answer: B
Excess refrigerant raises head and subcooling.
8. A start capacitor provides:
A. Continuous torque
B. Starting torque
C. Voltage regulation
D. Phase balance
Correct Answer: B
Start capacitors boost motor starting torque.
9. Ohm's Law is:
A. V = I/R
B. V = I × R
C. R = V × I
D. I = V × R
Correct Answer: B
Voltage equals current times resistance.
10. A clamp meter measures:
A. Voltage
B. Current
C. Resistance
, D. Capacitance
Correct Answer: B
Clamp meters read current inductively.
11. A pressure relief valve protects against:
A. Low charge
B. Excess pressure
C. Voltage spikes
D. Ice buildup
Correct Answer: B
It vents at unsafe pressure limits.
12. An economizer saves energy by:
A. Boosting compressor
B. Using outdoor air
C. Heating refrigerant
D. Increasing charge
Correct Answer: B
Free cooling uses cool outdoor air.
13. A heat pump reverses flow using a:
A. Contactor
B. Reversing valve
C. Relay
D. Thermostat
Correct Answer: B
The reversing valve swaps coil functions.
