MASSACHUSETTS HVAC TECHNICIAN QUESTIONS AND
CORRECT ANSWERS (VERIFIED ANSWERS) Q&A 2026
|INSTANT DOWNLOAD PDF
1. What is the primary purpose of a thermostat in an HVAC
system?
A. To increase the airflow in ductwork
B. To regulate temperature by controlling the system *
C. To clean the air of dust particles
D. To circulate refrigerant
Rationale: The thermostat senses room temperature and
signals the HVAC system to turn on or off to maintain the
desired temperature.
2. Which type of refrigerant is commonly used in modern
residential air conditioning systems?
A. R-12
B. R-22
C. R-410A *
D. R-134
Rationale: R-410A is non-ozone-depleting and widely used in
new residential AC units, replacing older R-22 systems.
,3. What is the function of a compressor in a refrigeration
cycle?
A. To absorb heat from indoor air
B. To increase refrigerant pressure and circulate it *
C. To filter contaminants in the refrigerant
D. To reduce system pressure
Rationale: The compressor raises the refrigerant pressure so it
can release heat in the condenser and continue the cycle.
4. Which tool is used to measure electrical current in an HVAC
system?
A. Thermometer
B. Clamp meter *
C. Manometer
D. Pressure gauge
Rationale: A clamp meter allows technicians to safely measure
current without breaking the circuit.
5. What is the primary reason for installing an expansion valve
in a refrigeration system?
A. To filter refrigerant
B. To reduce refrigerant pressure and control flow *
C. To heat the refrigerant
D. To increase airflow
,Rationale: The expansion valve lowers refrigerant pressure,
allowing it to evaporate and absorb heat efficiently in the
evaporator coil.
6. Which type of airflow is required for proper HVAC system
operation?
A. Laminar airflow
B. Restricted airflow
C. Unobstructed airflow *
D. Random airflow
Rationale: Proper airflow ensures efficient heat exchange and
prevents system damage due to freezing or overheating.
7. In a split AC system, where is the evaporator coil located?
A. Outside the building
B. Inside the air handler or furnace *
C. In the condenser unit
D. In the ductwork
Rationale: The evaporator coil absorbs heat from indoor air and
is typically located in the air handler.
8. What does SEER stand for in air conditioning systems?
, A. Seasonal Energy Efficiency Ratio *
B. Standard Energy Evaluation Rating
C. System Efficiency and Energy Ratio
D. Seasonal Electrical Energy Requirement
Rationale: SEER measures cooling efficiency over a typical
cooling season. Higher SEER indicates better energy efficiency.
9. Which safety device prevents excessive pressure in a
refrigerant system?
A. Expansion valve
B. Pressure relief valve *
C. Check valve
D. Solenoid valve
Rationale: The pressure relief valve opens to prevent damage
when system pressure exceeds safe limits.
10. Which type of heat pump can provide both heating and
cooling?
A. Air-source heat pump *
B. Ground-source heat pump
C. Gas furnace
D. Evaporative cooler
Rationale: Air-source heat pumps reverse refrigerant flow to
switch between heating and cooling modes.
CORRECT ANSWERS (VERIFIED ANSWERS) Q&A 2026
|INSTANT DOWNLOAD PDF
1. What is the primary purpose of a thermostat in an HVAC
system?
A. To increase the airflow in ductwork
B. To regulate temperature by controlling the system *
C. To clean the air of dust particles
D. To circulate refrigerant
Rationale: The thermostat senses room temperature and
signals the HVAC system to turn on or off to maintain the
desired temperature.
2. Which type of refrigerant is commonly used in modern
residential air conditioning systems?
A. R-12
B. R-22
C. R-410A *
D. R-134
Rationale: R-410A is non-ozone-depleting and widely used in
new residential AC units, replacing older R-22 systems.
,3. What is the function of a compressor in a refrigeration
cycle?
A. To absorb heat from indoor air
B. To increase refrigerant pressure and circulate it *
C. To filter contaminants in the refrigerant
D. To reduce system pressure
Rationale: The compressor raises the refrigerant pressure so it
can release heat in the condenser and continue the cycle.
4. Which tool is used to measure electrical current in an HVAC
system?
A. Thermometer
B. Clamp meter *
C. Manometer
D. Pressure gauge
Rationale: A clamp meter allows technicians to safely measure
current without breaking the circuit.
5. What is the primary reason for installing an expansion valve
in a refrigeration system?
A. To filter refrigerant
B. To reduce refrigerant pressure and control flow *
C. To heat the refrigerant
D. To increase airflow
,Rationale: The expansion valve lowers refrigerant pressure,
allowing it to evaporate and absorb heat efficiently in the
evaporator coil.
6. Which type of airflow is required for proper HVAC system
operation?
A. Laminar airflow
B. Restricted airflow
C. Unobstructed airflow *
D. Random airflow
Rationale: Proper airflow ensures efficient heat exchange and
prevents system damage due to freezing or overheating.
7. In a split AC system, where is the evaporator coil located?
A. Outside the building
B. Inside the air handler or furnace *
C. In the condenser unit
D. In the ductwork
Rationale: The evaporator coil absorbs heat from indoor air and
is typically located in the air handler.
8. What does SEER stand for in air conditioning systems?
, A. Seasonal Energy Efficiency Ratio *
B. Standard Energy Evaluation Rating
C. System Efficiency and Energy Ratio
D. Seasonal Electrical Energy Requirement
Rationale: SEER measures cooling efficiency over a typical
cooling season. Higher SEER indicates better energy efficiency.
9. Which safety device prevents excessive pressure in a
refrigerant system?
A. Expansion valve
B. Pressure relief valve *
C. Check valve
D. Solenoid valve
Rationale: The pressure relief valve opens to prevent damage
when system pressure exceeds safe limits.
10. Which type of heat pump can provide both heating and
cooling?
A. Air-source heat pump *
B. Ground-source heat pump
C. Gas furnace
D. Evaporative cooler
Rationale: Air-source heat pumps reverse refrigerant flow to
switch between heating and cooling modes.
