NATE INDUSTRY COMPETENCY EXAM

NATE INDUSTRY COMPETENCY EXAM

COMMERCIAL REFRIGERATION LATEST EXAM 2023

ACTUAL EXAM 100 QUESTIONS AND CORRECT

DETAILED ANSWERS WITH RATIONALES (VERIFIED

ANSWERS) |ALREADY GRADED A+

What is the primary function of a refrigerant distributor at the outlet of a thermostatic expansion valve?

• Allow the evaporator to operate with proper superheat.
• Feed the evaporator sufficient liquid to control the leaving air

temperature.

• Decrease the pressure drop across the evaporator coil.
• Evenly feed each evaporator circuit. - ANSWER- D

The voltage that controls the operation of the contact points in a

potential relay is:

• Line voltage.
• Run-winding voltage.
• Back EMF.
• Control voltage. - ANSWER- C

Refrigerant migration can be minimized by the use of a(n)

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• Oil separator.
• Receiver tank.
• Liquid line solenoid valve.
• Crankcase pressure regulating valve. - ANSWER- C

A transformer rated at 40 VA at 24 volts output has a maximum capacity

of:

• 0.625 A.
• 0.960 A.
• 1.240 A.
• 1.667 A. - ANSWER- D

Using the illustration below, what is the pressure drop across the refrigerant distributor and distributor tubes?

• 2.5 psi.
• 35 psi.
• 71 psi.
• 120 psi. - ANSWER- B

The current that opens the contacts in the current relay is the:

• Start-winding current. 2 / 4

• Run-winding current.
• 24-volt applied voltage.
• Back EMF. - ANSWER- D

The holding coil of the potential start relay is connected across:

• The run-winding and common.
• The start-winding and common.
• Both run and start windings.
• The line voltage. - ANSWER- B

In a pump-down refrigeration system, the compressor is cycled on and

off by the:

• Temperature control.
• Low pressure control.
• Head pressure control.
• Liquid solenoid valve. - ANSWER- B

Low ambient head pressure controls in a condensing unit function by

controlling flooding of liquid refrigerant in the:

• Receiver.
• Accumulator. 3 / 4

• Evaporator.
• Condenser. - ANSWER- D

As head pressure increases while suction pressure remains constant, the

compressor current:

• Increases and capacity increases.
• Decreases and capacity increases.
• Increases and capacity decreases.
• Increases and capacity remains constant. - ANSWER- B

On an inside 30 lb. receiver with a safety-pressure relief device, the

discharge of the safety device should be piped to the:

• Inside compressor.
• Outside condenser.
• Outside atmosphere.
• Inside evaporator. - ANSWER- C

On a new installation, the purpose of adjusting a thermostatic expansion

valve to maintain a low superheat is to ensure that:

• The liquid refrigerant will boil off as quickly as possible in the

evaporator.

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