New York HVAC Technician License
Examination Practice Questions And
Correct Answers (Verified Answers) Plus
Rationales 2025|2026 Q&A | Instant
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1. What is the primary function of an expansion valve in a refrigeration
system?
A. Increase refrigerant pressure
B. Compress refrigerant vapor
C. Control refrigerant flow into the evaporator
D. Remove non-condensables
The expansion valve meters refrigerant to maintain proper superheat
in the evaporator and controls flow, not pressure increase.
2. Which refrigerant is classified as having zero ozone depletion potential
(ODP)?
, A. R-22
B. R-11
C. R-134a
D. R-12
R-134a has zero ODP though it has global warming potential.
3. What tool is used to measure superheat in an HVAC system?
A. Vacuum pump
B. Thermometer and pressure gauge
C. Leak detector
D. Psychrometer
Superheat is calculated using temperature and pressure readings at
the evaporator outlet.
4. What is the typical color of an acetylene cylinder?
A. Blue
B. Maroon
C. Green
D. Yellow
Standard cylinder colors: oxygen is green, acetylene is maroon.
5. What is the maximum safe working pressure for standard R-410A
service hoses?
A. 200 psi
B. 400 psi
C. 500 psi
, D. 800 psi
R-410A operates at higher pressures, requiring hoses rated at least
800 psi working pressure.
6. Which component removes moisture and contaminants from the
refrigerant?
A. Condenser
B. Evaporator
C. Filter-drier
D. Sight glass
Filter-driers contain desiccant to absorb moisture and filter debris.
7. What is the function of the condenser in the refrigeration cycle?
A. Absorb heat from space
B. Reject heat to surroundings
C. Compress refrigerant
D. Regulate refrigerant flow
The condenser rejects heat absorbed in the evaporator plus
compressor heat.
8. What electrical device protects a motor from overload?
A. Contactor
B. Overload relay
C. Transformer
D. Capacitor
Overload relays trip circuits when motor current exceeds safe limits.
, 9. What is the minimum evacuation level for systems containing less
than 200 pounds of refrigerant (per EPA Section 608)?
A. 1000 microns
B. 2000 microns
C. 500 microns
D. 150 microns
EPA requires 500 microns for high vacuum evacuation of most
systems.
10. In psychrometrics, relative humidity is defined as:
A. Amount of moisture air can hold
B. Ratio of actual moisture content to maximum at same
temperature
C. Temperature at which condensation begins
D. Dew point
Relative humidity expresses actual water vapor compared to
saturation point.
11. The purpose of a crankcase heater in a compressor is to:
A. Increase oil viscosity
B. Prevent refrigerant migration into crankcase
C. Reduce discharge pressure
D. Control superheat
Examination Practice Questions And
Correct Answers (Verified Answers) Plus
Rationales 2025|2026 Q&A | Instant
Download Pdf
1. What is the primary function of an expansion valve in a refrigeration
system?
A. Increase refrigerant pressure
B. Compress refrigerant vapor
C. Control refrigerant flow into the evaporator
D. Remove non-condensables
The expansion valve meters refrigerant to maintain proper superheat
in the evaporator and controls flow, not pressure increase.
2. Which refrigerant is classified as having zero ozone depletion potential
(ODP)?
, A. R-22
B. R-11
C. R-134a
D. R-12
R-134a has zero ODP though it has global warming potential.
3. What tool is used to measure superheat in an HVAC system?
A. Vacuum pump
B. Thermometer and pressure gauge
C. Leak detector
D. Psychrometer
Superheat is calculated using temperature and pressure readings at
the evaporator outlet.
4. What is the typical color of an acetylene cylinder?
A. Blue
B. Maroon
C. Green
D. Yellow
Standard cylinder colors: oxygen is green, acetylene is maroon.
5. What is the maximum safe working pressure for standard R-410A
service hoses?
A. 200 psi
B. 400 psi
C. 500 psi
, D. 800 psi
R-410A operates at higher pressures, requiring hoses rated at least
800 psi working pressure.
6. Which component removes moisture and contaminants from the
refrigerant?
A. Condenser
B. Evaporator
C. Filter-drier
D. Sight glass
Filter-driers contain desiccant to absorb moisture and filter debris.
7. What is the function of the condenser in the refrigeration cycle?
A. Absorb heat from space
B. Reject heat to surroundings
C. Compress refrigerant
D. Regulate refrigerant flow
The condenser rejects heat absorbed in the evaporator plus
compressor heat.
8. What electrical device protects a motor from overload?
A. Contactor
B. Overload relay
C. Transformer
D. Capacitor
Overload relays trip circuits when motor current exceeds safe limits.
, 9. What is the minimum evacuation level for systems containing less
than 200 pounds of refrigerant (per EPA Section 608)?
A. 1000 microns
B. 2000 microns
C. 500 microns
D. 150 microns
EPA requires 500 microns for high vacuum evacuation of most
systems.
10. In psychrometrics, relative humidity is defined as:
A. Amount of moisture air can hold
B. Ratio of actual moisture content to maximum at same
temperature
C. Temperature at which condensation begins
D. Dew point
Relative humidity expresses actual water vapor compared to
saturation point.
11. The purpose of a crankcase heater in a compressor is to:
A. Increase oil viscosity
B. Prevent refrigerant migration into crankcase
C. Reduce discharge pressure
D. Control superheat
