HVAC JOURNEYMAN EXAM AND PREP TEST
2026/2027 Complete Questions and Answers Detailed
Rationales Pass Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Refrigeration Principles and Cycle | Q1 – Q10
Section 2 | Electrical Components and Controls | Q11 – Q20
Section 3 | Heating Systems (Gas, Oil, Electric, Heat Pumps) | Q21 – Q30
Section 4 | Air Distribution, Duct Design, and Ventilation | Q31 – Q40
Section 5 | Safety, Tools, and EPA Regulations | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: REFRIGERATION PRINCIPLES AND CYCLE Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 45-year-old service technician is called to a restaurant walk-in cooler that is not
maintaining temperature. The system uses R-404A. The suction pressure reads 65 psig,
the discharge pressure reads 280 psig, and the ambient temperature is 85°F. The box
temperature is 38°F. During inspection, the tech notices frost on the suction line
extending all the way back to the compressor. What is the most likely cause of this
condition?
A. The system is slightly undercharged and needs approximately 2 pounds of refrigerant
B. The thermostatic expansion valve is overfeeding, causing liquid floodback to the
compressor ✓ CORRECT
C. The condenser fan motor is running in reverse and recirculating hot air
D. The head pressure control is set too high and is forcing excess refrigerant into the
evaporator
Correct Answer: B
,Rationale: Frost on the suction line extending back to the compressor indicates liquid
refrigerant is returning to the compressor, which occurs when the thermostatic
expansion valve overfeeds the evaporator. An undercharge would produce a hot suction
line and inadequate cooling, not frost back to the compressor. Proper superheat should
be 8°F to 12°F at the compressor inlet to prevent slugging and bearing washout.
Question 2 of 50
A 52-year-old contractor is inspecting a newly installed residential split system charged
with R-410A. The indoor wet bulb is 67°F and the outdoor dry bulb is 95°F. He measures
the suction line temperature at the evaporator outlet at 48°F, and the saturated suction
temperature at the same point is 38°F. What do these readings indicate?
A. The system has a significant overcharge of refrigerant that requires immediate
recovery
B. The evaporator is severely restricted and starving for refrigerant
C. The compressor amp draw is below specification and the motor is failing
D. The system has approximately 10°F of superheat, indicating the metering device is
properly adjusted ✓ CORRECT
Correct Answer: D
Rationale: Ten degrees of superheat at the evaporator outlet indicates the refrigerant
has fully boiled and picked up sensible heat, confirming the metering device is properly
adjusted for the load. An evaporator restriction would produce excessively high
superheat and low suction pressure, while an overcharge would drive superheat toward
zero and risk liquid floodback. Superheat measurements should always be taken with
stable indoor and outdoor conditions for accuracy.
Question 3 of 50
A 38-year-old service technician responds to a call about a 5-ton rooftop unit that is
blowing warm air. She finds the sight glass shows continuous bubbles, the receiver
,feels cold to the touch, and the liquid line temperature at the condenser outlet is 95°F
while the ambient temperature is 90°F. What is the most likely cause of the warm air
complaint?
A. The system has a low refrigerant charge, indicated by bubbles in the sight glass and
minimal liquid in the receiver ✓ CORRECT
B. The condenser coils are severely dirty and need immediate chemical cleaning
C. The evaporator fan is running too slowly and failing to draw adequate airflow
D. The crankcase heater has failed and allowed refrigerant to migrate into the
compressor
Correct Answer: A
Rationale: Bubbles in the sight glass combined with a cold receiver indicate insufficient
liquid refrigerant in the system, which is consistent with a low charge. A dirty condenser
would elevate head pressure and subcooling rather than produce bubbles, and a failed
crankcase heater causes flooded starts during off-cycles without creating sight glass
bubbles. The low charge causes flashing at the metering device and reduced cooling
capacity.
Question 4 of 50
A 41-year-old journeyman is troubleshooting a commercial ice machine on a hot
summer afternoon. The high-pressure cutout trips intermittently when the outdoor
temperature climbs above 95°F. With the system running, the head pressure reads 400
psig on R-404A and the ambient temperature is 90°F. The condenser coils were
chemically cleaned last week. What should he investigate next?
A. Replace the high-pressure control with a higher-pressure setting to prevent nuisance
trips
B. Add refrigerant to the system to increase the suction pressure and balance the cycle
C. Verify the condenser fan is moving the correct CFM and check for non-condensables
in the system ✓ CORRECT
D. Install a larger evaporator to reduce the overall load on the compressor
, Correct Answer: C
Rationale: An abnormally high head pressure with clean condenser coils points to
inadequate air volume across the condenser or non-condensable gases trapped in the
system. Raising the high-pressure control setting or adding refrigerant would mask the
problem and risk compressor damage, while verifying fan performance and purging
non-condensables addresses the root cause. Always measure actual airflow before
condemning a compressor.
Question 5 of 50
A 29-year-old apprentice is recovering refrigerant from a residential split system on a
summer day. The recovery cylinder is sitting in direct sunlight on the truck bed and the
ambient temperature is 98°F. The pressure gauge on the recovery tank reads 375 psig.
What should the apprentice do immediately?
A. Continue recovery since R-410A recovery tanks are rated for pressures above 400
psig
B. Move the recovery cylinder to shade and cool it with water to prevent overpressure
and potential rupture ✓ CORRECT
C. Open the tank valve slightly to vent excess pressure before continuing
D. Switch to a larger diameter recovery hose to speed up the transfer and reduce tank
pressure
Correct Answer: B
Rationale: Recovery cylinders in direct sunlight can exceed their pressure rating as
temperature rises, creating a rupture hazard that endangers everyone nearby. Venting
refrigerant violates EPA regulations and wastes product, while switching hoses does
nothing to reduce cylinder pressure. Water cooling is the standard field practice to keep
recovery tank pressures within safe limits during hot weather.
Question 6 of 50
2026/2027 Complete Questions and Answers Detailed
Rationales Pass Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Refrigeration Principles and Cycle | Q1 – Q10
Section 2 | Electrical Components and Controls | Q11 – Q20
Section 3 | Heating Systems (Gas, Oil, Electric, Heat Pumps) | Q21 – Q30
Section 4 | Air Distribution, Duct Design, and Ventilation | Q31 – Q40
Section 5 | Safety, Tools, and EPA Regulations | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: REFRIGERATION PRINCIPLES AND CYCLE Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 45-year-old service technician is called to a restaurant walk-in cooler that is not
maintaining temperature. The system uses R-404A. The suction pressure reads 65 psig,
the discharge pressure reads 280 psig, and the ambient temperature is 85°F. The box
temperature is 38°F. During inspection, the tech notices frost on the suction line
extending all the way back to the compressor. What is the most likely cause of this
condition?
A. The system is slightly undercharged and needs approximately 2 pounds of refrigerant
B. The thermostatic expansion valve is overfeeding, causing liquid floodback to the
compressor ✓ CORRECT
C. The condenser fan motor is running in reverse and recirculating hot air
D. The head pressure control is set too high and is forcing excess refrigerant into the
evaporator
Correct Answer: B
,Rationale: Frost on the suction line extending back to the compressor indicates liquid
refrigerant is returning to the compressor, which occurs when the thermostatic
expansion valve overfeeds the evaporator. An undercharge would produce a hot suction
line and inadequate cooling, not frost back to the compressor. Proper superheat should
be 8°F to 12°F at the compressor inlet to prevent slugging and bearing washout.
Question 2 of 50
A 52-year-old contractor is inspecting a newly installed residential split system charged
with R-410A. The indoor wet bulb is 67°F and the outdoor dry bulb is 95°F. He measures
the suction line temperature at the evaporator outlet at 48°F, and the saturated suction
temperature at the same point is 38°F. What do these readings indicate?
A. The system has a significant overcharge of refrigerant that requires immediate
recovery
B. The evaporator is severely restricted and starving for refrigerant
C. The compressor amp draw is below specification and the motor is failing
D. The system has approximately 10°F of superheat, indicating the metering device is
properly adjusted ✓ CORRECT
Correct Answer: D
Rationale: Ten degrees of superheat at the evaporator outlet indicates the refrigerant
has fully boiled and picked up sensible heat, confirming the metering device is properly
adjusted for the load. An evaporator restriction would produce excessively high
superheat and low suction pressure, while an overcharge would drive superheat toward
zero and risk liquid floodback. Superheat measurements should always be taken with
stable indoor and outdoor conditions for accuracy.
Question 3 of 50
A 38-year-old service technician responds to a call about a 5-ton rooftop unit that is
blowing warm air. She finds the sight glass shows continuous bubbles, the receiver
,feels cold to the touch, and the liquid line temperature at the condenser outlet is 95°F
while the ambient temperature is 90°F. What is the most likely cause of the warm air
complaint?
A. The system has a low refrigerant charge, indicated by bubbles in the sight glass and
minimal liquid in the receiver ✓ CORRECT
B. The condenser coils are severely dirty and need immediate chemical cleaning
C. The evaporator fan is running too slowly and failing to draw adequate airflow
D. The crankcase heater has failed and allowed refrigerant to migrate into the
compressor
Correct Answer: A
Rationale: Bubbles in the sight glass combined with a cold receiver indicate insufficient
liquid refrigerant in the system, which is consistent with a low charge. A dirty condenser
would elevate head pressure and subcooling rather than produce bubbles, and a failed
crankcase heater causes flooded starts during off-cycles without creating sight glass
bubbles. The low charge causes flashing at the metering device and reduced cooling
capacity.
Question 4 of 50
A 41-year-old journeyman is troubleshooting a commercial ice machine on a hot
summer afternoon. The high-pressure cutout trips intermittently when the outdoor
temperature climbs above 95°F. With the system running, the head pressure reads 400
psig on R-404A and the ambient temperature is 90°F. The condenser coils were
chemically cleaned last week. What should he investigate next?
A. Replace the high-pressure control with a higher-pressure setting to prevent nuisance
trips
B. Add refrigerant to the system to increase the suction pressure and balance the cycle
C. Verify the condenser fan is moving the correct CFM and check for non-condensables
in the system ✓ CORRECT
D. Install a larger evaporator to reduce the overall load on the compressor
, Correct Answer: C
Rationale: An abnormally high head pressure with clean condenser coils points to
inadequate air volume across the condenser or non-condensable gases trapped in the
system. Raising the high-pressure control setting or adding refrigerant would mask the
problem and risk compressor damage, while verifying fan performance and purging
non-condensables addresses the root cause. Always measure actual airflow before
condemning a compressor.
Question 5 of 50
A 29-year-old apprentice is recovering refrigerant from a residential split system on a
summer day. The recovery cylinder is sitting in direct sunlight on the truck bed and the
ambient temperature is 98°F. The pressure gauge on the recovery tank reads 375 psig.
What should the apprentice do immediately?
A. Continue recovery since R-410A recovery tanks are rated for pressures above 400
psig
B. Move the recovery cylinder to shade and cool it with water to prevent overpressure
and potential rupture ✓ CORRECT
C. Open the tank valve slightly to vent excess pressure before continuing
D. Switch to a larger diameter recovery hose to speed up the transfer and reduce tank
pressure
Correct Answer: B
Rationale: Recovery cylinders in direct sunlight can exceed their pressure rating as
temperature rises, creating a rupture hazard that endangers everyone nearby. Venting
refrigerant violates EPA regulations and wastes product, while switching hoses does
nothing to reduce cylinder pressure. Water cooling is the standard field practice to keep
recovery tank pressures within safe limits during hot weather.
Question 6 of 50
