(ENTRY-LEVEL)
Questions And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant Download Pdf
NURSE CELESTINE
,1. What is the primary function of a thermostat in an HVAC system?
A. To circulate refrigerant
B. To sense temperature and control system operation
C. To compress refrigerant
D. To filter air
The thermostat monitors space temperature and signals heating
or cooling equipment to turn on or off.
2. Which component raises the pressure and temperature of
refrigerant vapor?
A. Evaporator
B. Condenser
C. Compressor
D. Expansion valve
The compressor increases refrigerant pressure so heat can be
rejected in the condenser.
3. Which refrigerant property allows heat absorption in the
evaporator?
A. High viscosity
B. Low boiling point
C. High density
, D. Chemical stability
Refrigerants boil at low temperatures, allowing them to absorb
heat efficiently.
4. What type of current is commonly used in residential HVAC
equipment?
A. Direct current (DC)
B. Alternating current (AC)
C. Pulsed current
D. Static current
Most residential systems operate on AC power supplied by utilities.
5. What is the main purpose of an air filter?
A. Increase airflow
B. Remove dust and contaminants
C. Cool the air
D. Reduce noise
Filters protect equipment and improve indoor air quality by
trapping particles.
6. Which meter is used to measure electrical resistance?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Wattmeter
An ohmmeter measures resistance in electrical circuits.
7. What happens to refrigerant in the condenser?
A. It evaporates
B. It expands
C. It releases heat and condenses to liquid