Utah S350 HVAC Contractor Examination
Newest Evaluated Exam Practice 120
Questions 2026-2027|Original Questions &
Answers |Detailed Rationales |*Hinted*
Complete Exam Prep Graded A+**Instant
Download Pdf**
1. Which condition most directly increases the sensible cooling load of a
building?
A. Reduced outdoor-air ventilation
B. Increased insulation thickness
C. Increased solar heat gain through glazing
D. Reduced lighting wattage
Answer: C. Increased solar heat gain through glazing
Solar radiation entering through windows adds sensible heat to the conditioned
space and increases the required cooling capacity.
2. A heat pump operates in cooling mode, but the indoor coil begins icing
while indoor airflow is confirmed adequate. Which condition should be
investigated first?
A. Excessively high indoor humidity only
B. Low refrigerant charge or restricted refrigerant flow
C. Oversized outdoor fan
D. Excessive condenser airflow
Answer: B. Low refrigerant charge or restricted refrigerant flow
Insufficient refrigerant or a restriction can reduce evaporator pressure and
temperature enough to cause coil icing.
, 3. Which component reverses refrigerant flow in a typical air-source heat
pump?
A. Accumulator
B. Receiver
C. Four-way reversing valve
D. Thermal expansion valve
Answer: C. Four-way reversing valve
The reversing valve changes the direction of refrigerant flow so the indoor and
outdoor coils exchange their heating and cooling functions.
4. What is the primary purpose of Manual J in residential HVAC design?
A. Selecting refrigerant piping sizes
B. Calculating residential heating and cooling loads
C. Designing electrical branch circuits
D. Determining gas-pipe pressure
Answer: B. Calculating residential heating and cooling loads
Manual J is used to determine the design heating and cooling loads needed for
residential equipment sizing.
5. A duct system has excessive static pressure and inadequate airflow at
several supply registers. Which condition is most likely contributing to the
problem?
A. Oversized return ductwork
B. Excessively restrictive ductwork
C. Low outdoor temperature
D. High condenser airflow
Answer: B. Excessively restrictive ductwork
High duct resistance increases static pressure and reduces the airflow delivered by
the blower.
, 6. Which instrument is most appropriate for measuring static pressure in an
HVAC duct system?
A. Psychrometer
B. Manometer
C. Megohmmeter
D. Tachometer
Answer: B. Manometer
A manometer measures pressure differences, including the static pressure
commonly evaluated during duct-system testing.
7. A system has a return-air temperature of 75°F and a supply-air temperature
of 55°F. What is the air-temperature split?
A. 10°F
B. 15°F
C. 20°F
D. 25°F
Answer: C. 20°F
The temperature difference is 75°F − 55°F = 20°F.
8. What is the principal purpose of an expansion device in a vapor-
compression refrigeration system?
A. Increase condenser pressure
B. Reduce refrigerant pressure before evaporation
C. Increase compressor discharge temperature
D. Remove noncondensable gases
Answer: B. Reduce refrigerant pressure before evaporation
The expansion device meters refrigerant into the evaporator while producing the
pressure drop necessary for evaporation.
9. Which sequence correctly represents the basic vapor-compression
refrigeration cycle?
, A. Compressor → evaporator → condenser → expansion device
B. Evaporator → compressor → condenser → expansion device
C. Condenser → compressor → evaporator → receiver
D. Compressor → expansion device → condenser → evaporator
Answer: B. Evaporator → compressor → condenser → expansion device
Refrigerant leaves the evaporator, enters the compressor, condenses in the
condenser, and then passes through the expansion device before returning to the
evaporator.
10.What is the primary function of a compressor?
A. Remove moisture from refrigerant
B. Raise refrigerant vapor pressure and temperature
C. Lower condenser pressure
D. Meter liquid refrigerant
Answer: B. Raise refrigerant vapor pressure and temperature
The compressor receives low-pressure vapor and compresses it into a higher-
pressure, higher-temperature vapor.
11.Which condition generally causes a lower-than-normal evaporator
pressure?
A. Excessive evaporator airflow
B. Low refrigerant charge
C. Excessively high suction pressure
D. Excessive indoor heat load
Answer: B. Low refrigerant charge
A low refrigerant charge commonly reduces refrigerant mass flow through the
evaporator and can result in abnormally low suction pressure.
12.What is the primary purpose of superheat measurement at an evaporator
outlet?
Newest Evaluated Exam Practice 120
Questions 2026-2027|Original Questions &
Answers |Detailed Rationales |*Hinted*
Complete Exam Prep Graded A+**Instant
Download Pdf**
1. Which condition most directly increases the sensible cooling load of a
building?
A. Reduced outdoor-air ventilation
B. Increased insulation thickness
C. Increased solar heat gain through glazing
D. Reduced lighting wattage
Answer: C. Increased solar heat gain through glazing
Solar radiation entering through windows adds sensible heat to the conditioned
space and increases the required cooling capacity.
2. A heat pump operates in cooling mode, but the indoor coil begins icing
while indoor airflow is confirmed adequate. Which condition should be
investigated first?
A. Excessively high indoor humidity only
B. Low refrigerant charge or restricted refrigerant flow
C. Oversized outdoor fan
D. Excessive condenser airflow
Answer: B. Low refrigerant charge or restricted refrigerant flow
Insufficient refrigerant or a restriction can reduce evaporator pressure and
temperature enough to cause coil icing.
, 3. Which component reverses refrigerant flow in a typical air-source heat
pump?
A. Accumulator
B. Receiver
C. Four-way reversing valve
D. Thermal expansion valve
Answer: C. Four-way reversing valve
The reversing valve changes the direction of refrigerant flow so the indoor and
outdoor coils exchange their heating and cooling functions.
4. What is the primary purpose of Manual J in residential HVAC design?
A. Selecting refrigerant piping sizes
B. Calculating residential heating and cooling loads
C. Designing electrical branch circuits
D. Determining gas-pipe pressure
Answer: B. Calculating residential heating and cooling loads
Manual J is used to determine the design heating and cooling loads needed for
residential equipment sizing.
5. A duct system has excessive static pressure and inadequate airflow at
several supply registers. Which condition is most likely contributing to the
problem?
A. Oversized return ductwork
B. Excessively restrictive ductwork
C. Low outdoor temperature
D. High condenser airflow
Answer: B. Excessively restrictive ductwork
High duct resistance increases static pressure and reduces the airflow delivered by
the blower.
, 6. Which instrument is most appropriate for measuring static pressure in an
HVAC duct system?
A. Psychrometer
B. Manometer
C. Megohmmeter
D. Tachometer
Answer: B. Manometer
A manometer measures pressure differences, including the static pressure
commonly evaluated during duct-system testing.
7. A system has a return-air temperature of 75°F and a supply-air temperature
of 55°F. What is the air-temperature split?
A. 10°F
B. 15°F
C. 20°F
D. 25°F
Answer: C. 20°F
The temperature difference is 75°F − 55°F = 20°F.
8. What is the principal purpose of an expansion device in a vapor-
compression refrigeration system?
A. Increase condenser pressure
B. Reduce refrigerant pressure before evaporation
C. Increase compressor discharge temperature
D. Remove noncondensable gases
Answer: B. Reduce refrigerant pressure before evaporation
The expansion device meters refrigerant into the evaporator while producing the
pressure drop necessary for evaporation.
9. Which sequence correctly represents the basic vapor-compression
refrigeration cycle?
, A. Compressor → evaporator → condenser → expansion device
B. Evaporator → compressor → condenser → expansion device
C. Condenser → compressor → evaporator → receiver
D. Compressor → expansion device → condenser → evaporator
Answer: B. Evaporator → compressor → condenser → expansion device
Refrigerant leaves the evaporator, enters the compressor, condenses in the
condenser, and then passes through the expansion device before returning to the
evaporator.
10.What is the primary function of a compressor?
A. Remove moisture from refrigerant
B. Raise refrigerant vapor pressure and temperature
C. Lower condenser pressure
D. Meter liquid refrigerant
Answer: B. Raise refrigerant vapor pressure and temperature
The compressor receives low-pressure vapor and compresses it into a higher-
pressure, higher-temperature vapor.
11.Which condition generally causes a lower-than-normal evaporator
pressure?
A. Excessive evaporator airflow
B. Low refrigerant charge
C. Excessively high suction pressure
D. Excessive indoor heat load
Answer: B. Low refrigerant charge
A low refrigerant charge commonly reduces refrigerant mass flow through the
evaporator and can result in abnormally low suction pressure.
12.What is the primary purpose of superheat measurement at an evaporator
outlet?
