Oklahoma Refrigeration Journeyman
Exam Practice Questions And Correct
Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant
Download Pdf.
1. In a standard vapor-compression refrigeration system, the
compressor receives low-pressure refrigerant vapor from the
evaporator and raises both its pressure and temperature before
discharging it toward the condenser. Which statement best
describes the primary function of the compressor?
A. To reduce the refrigerant pressure so that it can evaporate at a lower
temperature
B. To remove moisture from the liquid refrigerant before it enters the
expansion device
C. To circulate refrigerant through the system while increasing the
vapor’s pressure and temperature
D. To convert high-pressure liquid refrigerant directly into low-pressure
vapor
,The compressor establishes refrigerant circulation and raises the
pressure and temperature of the suction vapor, preparing it for heat
rejection in the condenser.
2. A refrigeration technician measures voltage across a contactor coil
and finds the correct control voltage, but the contactor does not
pull in. Assuming the control circuit is properly energized, which
component condition is most likely responsible?
A. Open condenser coil
B. Restricted liquid line
C. Open or failed contactor coil
D. Low evaporator superheat
If the proper control voltage is present across the coil but the contactor
does not energize, an open or failed coil is a primary suspect.
3. When troubleshooting a refrigeration motor circuit, a technician
measures resistance through a motor winding with the power
disconnected. What does an extremely high or infinite resistance
reading generally indicate?
A. A properly energized winding
B. A shorted winding
C. A grounded winding with normal continuity
D. An open winding or broken electrical connection
,An infinite resistance reading indicates that current cannot pass through
the measured path, commonly because of an open winding, conductor,
or connection.
4. A single-phase refrigeration compressor uses a start winding and a
run winding. What is the principal purpose of the start winding
during startup?
A. To reduce condenser pressure
B. To maintain low evaporator pressure
C. To provide additional starting torque to bring the motor up to
operating speed
D. To prevent refrigerant migration during shutdown
The start winding creates the phase relationship necessary to develop
sufficient starting torque for the compressor motor.
5. A technician is using a multimeter to verify whether a refrigeration
control circuit is receiving power. Which measurement is normally
made first when determining whether the expected voltage is
present?
A. Resistance across an energized circuit
B. Voltage across the appropriate points in the circuit
C. Continuity through a pressurized refrigerant line
D. Capacitance across the condenser coil
, Voltage testing is the appropriate method for determining whether
electrical potential is present at a control point; resistance
measurements should generally be made on de-energized circuits.
6. A refrigeration system uses a normally closed low-pressure control
to stop the compressor when suction pressure falls below a
predetermined setting. Under normal operation, what happens to
the control contacts when suction pressure falls below its cutout
setting?
A. They close and energize the compressor
B. They open and interrupt the compressor control circuit
C. They reverse condenser-fan rotation
D. They open the liquid-line solenoid only
A low-pressure control protects and regulates the system by opening its
contacts when suction pressure falls to the specified cutout pressure.
7. A technician finds that a refrigeration compressor repeatedly trips
its overload protector shortly after startup. Which condition could
directly contribute to excessive motor current and overheating?
A. Excessively low condensing pressure
B. Excessively clean condenser fins
C. High head pressure or mechanical compressor overload
D. Correct refrigerant charge and normal airflow
Exam Practice Questions And Correct
Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant
Download Pdf.
1. In a standard vapor-compression refrigeration system, the
compressor receives low-pressure refrigerant vapor from the
evaporator and raises both its pressure and temperature before
discharging it toward the condenser. Which statement best
describes the primary function of the compressor?
A. To reduce the refrigerant pressure so that it can evaporate at a lower
temperature
B. To remove moisture from the liquid refrigerant before it enters the
expansion device
C. To circulate refrigerant through the system while increasing the
vapor’s pressure and temperature
D. To convert high-pressure liquid refrigerant directly into low-pressure
vapor
,The compressor establishes refrigerant circulation and raises the
pressure and temperature of the suction vapor, preparing it for heat
rejection in the condenser.
2. A refrigeration technician measures voltage across a contactor coil
and finds the correct control voltage, but the contactor does not
pull in. Assuming the control circuit is properly energized, which
component condition is most likely responsible?
A. Open condenser coil
B. Restricted liquid line
C. Open or failed contactor coil
D. Low evaporator superheat
If the proper control voltage is present across the coil but the contactor
does not energize, an open or failed coil is a primary suspect.
3. When troubleshooting a refrigeration motor circuit, a technician
measures resistance through a motor winding with the power
disconnected. What does an extremely high or infinite resistance
reading generally indicate?
A. A properly energized winding
B. A shorted winding
C. A grounded winding with normal continuity
D. An open winding or broken electrical connection
,An infinite resistance reading indicates that current cannot pass through
the measured path, commonly because of an open winding, conductor,
or connection.
4. A single-phase refrigeration compressor uses a start winding and a
run winding. What is the principal purpose of the start winding
during startup?
A. To reduce condenser pressure
B. To maintain low evaporator pressure
C. To provide additional starting torque to bring the motor up to
operating speed
D. To prevent refrigerant migration during shutdown
The start winding creates the phase relationship necessary to develop
sufficient starting torque for the compressor motor.
5. A technician is using a multimeter to verify whether a refrigeration
control circuit is receiving power. Which measurement is normally
made first when determining whether the expected voltage is
present?
A. Resistance across an energized circuit
B. Voltage across the appropriate points in the circuit
C. Continuity through a pressurized refrigerant line
D. Capacitance across the condenser coil
, Voltage testing is the appropriate method for determining whether
electrical potential is present at a control point; resistance
measurements should generally be made on de-energized circuits.
6. A refrigeration system uses a normally closed low-pressure control
to stop the compressor when suction pressure falls below a
predetermined setting. Under normal operation, what happens to
the control contacts when suction pressure falls below its cutout
setting?
A. They close and energize the compressor
B. They open and interrupt the compressor control circuit
C. They reverse condenser-fan rotation
D. They open the liquid-line solenoid only
A low-pressure control protects and regulates the system by opening its
contacts when suction pressure falls to the specified cutout pressure.
7. A technician finds that a refrigeration compressor repeatedly trips
its overload protector shortly after startup. Which condition could
directly contribute to excessive motor current and overheating?
A. Excessively low condensing pressure
B. Excessively clean condenser fins
C. High head pressure or mechanical compressor overload
D. Correct refrigerant charge and normal airflow
