Which of the following actions would always be considered \major\ under epa\s regulations?

Charged low pressure refrigeration machines may be most efficiently checked by:
A. Adding dry nitrogen
B. Adding HCFC 22
C. Raising system pressure by heating with circulated hot water or heating blankets
D. Operating the purge system

C. Raising system pressure by heating with circulated hot water or heating blankets

With a low pressure chiller, what must you do after recovering the liquid refrigerant?
A. Recover the vapor refrigerant
B. Pressurize system with nitrogen
C. Remove the oil from the system
D. Solvent flush entire system

A. Recover the vapor refrigerant

When removing oil from a low pressure system, the temperature should be 130F because:
A. You can warm your hands on the container
B. Less refrigerant will be contained in the oil at the higher temperature
C. Warmer oil has a lower viscosity and flows more easily
D. It shows that the heater is working

B. Less refrigerant will be contained in the oil at the higher temperature

After system servicing, why is refrigerant vapor re-introduced to the refrigeration system before refrigerant liquid?
A. Vapor charging increases pressure slowly, preventing failure of the rupture disk
B. Vapor charging is faster than liquid charging
C. Liquid charging is more difficult to control than vapor charging
D. Liquid charge into a deep vacuum will boil and may lower temperatures enough to freeze water in the tubes

D. Liquid charge into a deep vacuum will boil and may lower temperatures enough to freeze water in the tubes

Appliances need not be evacuated all the way to the prescribed level when:
A. The repair is major
B. The repair is followed by an evacuation of the appliance to the environment
C. Leaks in the appliance make evacuation to the prescribed level unattainable
D. The appliance is being disposed

C. Leaks in the appliance make evacuation to the prescribed level unattainable

Which of the following repairs would ALWAYS be considered "major" under EPA's regulations?
A. Replacement of an evaporator coil
B. Replacement of a drier filter
C. Replacement of a switch
D. Replacement of a purge unit

A. Replacement of an evaporator coil

After reaching the required recover vacuum on an appliance, you should:
A. Immediately disconnect the recycling or recovery equipment and open the system for service
B. Wait for at least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in liquid form or in the oil
C. Immediately break the vacuum with nitrogen and open the system for service
D. Immediately pressurize the system with nitrogen and perform a leak check

B. Wait for at least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in liquid form or in the oil

Which of the following WOULD NOT fall under the EPA definition for "Major maintenance -service -or repair"?
A. Replacing an oil
B. Replacing the compressor
C. Re-tubing a heat exchanger (condenser)
D. Replacing a fin and tube forced air evaporator coil

A. Replacing an oil filter

During vapor removal from a low pressure refrigeration system:
A. The system water pumps should be on, and the recovery compressor should be off
B. The system water pumps should be on, the recovery compressor should be on, and the recovery condenser water should be off
C. The water pumps, the recovery compressor, and the recovery condenser water should all be on
D. The system water pumps should be off, and the recovery compressor should be on

C. The water pumps, the recovery compressor, and the recovery condenser water should all be on

The PRIMARY purpose of a purge pump unit on a CFC 11 chiller is to:
A. Remove CFC's from the system
B. Condense air out of the system
C. Condense water out of the system
D. Remove non-condensable from the system

D. Remove non-condensable from the system