NYC Health Hospitals Senior Air
Conditioning Mechanic Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. A Senior Air Conditioning Mechanic working in a hospital environment
is responsible for maintaining critical HVAC systems that support
patient care areas, operating rooms, laboratories, and administrative
spaces. When troubleshooting a central air-conditioning system that
has lost cooling capacity, which diagnostic sequence is the most
appropriate approach?
A. Replace the compressor immediately, recharge the refrigerant, and then
inspect the electrical system
B. Check operating conditions, verify electrical controls, inspect airflow, and
then evaluate the refrigeration circuit
C. Increase thermostat settings, bypass safety controls, and observe system
,operation
D. Replace all filters, motors, and valves before performing any testing
Answer: B
A systematic HVAC diagnosis begins with gathering operating data,
checking controls and electrical components, verifying airflow, and then
analyzing refrigeration performance to avoid unnecessary component
replacement.
2. In a hospital chilled-water air-conditioning system, the primary
purpose of the chilled-water pump is to:
A. Increase refrigerant pressure inside the compressor
B. Circulate chilled water between the chiller and air-handling units
C. Remove moisture directly from conditioned spaces
D. Control the temperature of combustion gases
Answer: B
Chilled-water pumps move cooled water through piping circuits so air-
handling units can transfer heat from building air into the chilled-water
system.
3. A Senior Air Conditioning Mechanic observes that a reciprocating
compressor is short cycling repeatedly. Which condition is most likely
to cause this problem?
,A. Proper refrigerant charge and unrestricted airflow
B. Oversized compressor operation or faulty control settings
C. Clean condenser coils and correct voltage
D. Balanced airflow throughout the building
Answer: B
Short cycling often results from control problems, improper equipment
sizing, refrigerant issues, or safety controls activating due to abnormal
operating conditions.
4. In HVAC refrigeration systems, superheat is used primarily to
determine:
A. The temperature difference between supply and return air
B. The amount of refrigerant subcooling in the condenser
C. Whether refrigerant vapor leaving the evaporator is properly evaporated
D. The electrical resistance of compressor windings
Answer: C
Superheat measures the temperature increase of refrigerant vapor above
its boiling point and helps verify proper evaporator operation and
refrigerant metering.
5. A hospital air-handling unit has reduced airflow even though the
supply fan motor is operating correctly. The most likely cause is:
, A. A dirty filter or restricted duct system
B. Excessive refrigerant charge
C. A defective compressor crankcase heater
D. Low oil level in the condenser
Answer: A
Restricted filters, blocked ducts, or dirty coils reduce airflow even when the
fan motor is functioning normally.
6. When performing maintenance on HVAC equipment in a healthcare
facility, lockout/tagout procedures are required primarily to:
A. Improve equipment efficiency
B. Prevent unauthorized operation and protect workers from hazardous
energy
C. Reduce refrigerant pressure
D. Increase motor horsepower
Answer: B
Lockout/tagout prevents accidental energization of equipment while
maintenance is being performed, protecting technicians from electrical and
mechanical hazards.
7. The main function of an expansion valve in a refrigeration system is to:
A. Compress refrigerant vapor
B. Remove oil from refrigerant
Conditioning Mechanic Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. A Senior Air Conditioning Mechanic working in a hospital environment
is responsible for maintaining critical HVAC systems that support
patient care areas, operating rooms, laboratories, and administrative
spaces. When troubleshooting a central air-conditioning system that
has lost cooling capacity, which diagnostic sequence is the most
appropriate approach?
A. Replace the compressor immediately, recharge the refrigerant, and then
inspect the electrical system
B. Check operating conditions, verify electrical controls, inspect airflow, and
then evaluate the refrigeration circuit
C. Increase thermostat settings, bypass safety controls, and observe system
,operation
D. Replace all filters, motors, and valves before performing any testing
Answer: B
A systematic HVAC diagnosis begins with gathering operating data,
checking controls and electrical components, verifying airflow, and then
analyzing refrigeration performance to avoid unnecessary component
replacement.
2. In a hospital chilled-water air-conditioning system, the primary
purpose of the chilled-water pump is to:
A. Increase refrigerant pressure inside the compressor
B. Circulate chilled water between the chiller and air-handling units
C. Remove moisture directly from conditioned spaces
D. Control the temperature of combustion gases
Answer: B
Chilled-water pumps move cooled water through piping circuits so air-
handling units can transfer heat from building air into the chilled-water
system.
3. A Senior Air Conditioning Mechanic observes that a reciprocating
compressor is short cycling repeatedly. Which condition is most likely
to cause this problem?
,A. Proper refrigerant charge and unrestricted airflow
B. Oversized compressor operation or faulty control settings
C. Clean condenser coils and correct voltage
D. Balanced airflow throughout the building
Answer: B
Short cycling often results from control problems, improper equipment
sizing, refrigerant issues, or safety controls activating due to abnormal
operating conditions.
4. In HVAC refrigeration systems, superheat is used primarily to
determine:
A. The temperature difference between supply and return air
B. The amount of refrigerant subcooling in the condenser
C. Whether refrigerant vapor leaving the evaporator is properly evaporated
D. The electrical resistance of compressor windings
Answer: C
Superheat measures the temperature increase of refrigerant vapor above
its boiling point and helps verify proper evaporator operation and
refrigerant metering.
5. A hospital air-handling unit has reduced airflow even though the
supply fan motor is operating correctly. The most likely cause is:
, A. A dirty filter or restricted duct system
B. Excessive refrigerant charge
C. A defective compressor crankcase heater
D. Low oil level in the condenser
Answer: A
Restricted filters, blocked ducts, or dirty coils reduce airflow even when the
fan motor is functioning normally.
6. When performing maintenance on HVAC equipment in a healthcare
facility, lockout/tagout procedures are required primarily to:
A. Improve equipment efficiency
B. Prevent unauthorized operation and protect workers from hazardous
energy
C. Reduce refrigerant pressure
D. Increase motor horsepower
Answer: B
Lockout/tagout prevents accidental energization of equipment while
maintenance is being performed, protecting technicians from electrical and
mechanical hazards.
7. The main function of an expansion valve in a refrigeration system is to:
A. Compress refrigerant vapor
B. Remove oil from refrigerant
