Refrigeration and Air Conditioning Quiz

Which causes considerable ice build-up around a TEV?

• High evaporator load

• Evaporator fan failing

• Defrost failing

• Short of refrigerant

Which refrigerant listed below is A3?

• R404a

• R1234yf

• R717

• R290

Which of the following is used to transfer waste refrigerant from HCFC system to a storage cylinder?

• Recovery unit

• Vacuum pump

• Reclaim unit

• Oil sump pump

What would indicate that there had been a leak on a pressure relief valve on a liquid receiver?

• Excessive oil staining

• Condensation on the PRV

• Partial frosting on the valve

• Sweating on the outside of the receiver

If a leak occurs on a service valve, where is it likely around?

• The cap

• The service valve key

• The gland nut

• The stem

Excessive superheat across a direct expansion evaporator in a supermarket frozen food case is likely caused by:

• Evaporator fans turned off

• Damaged evaporator fins

• Partially blocked EEV strainer

• Overcharge of refrigerant

The reference point of a Celsius thermometer is taken from?

• -10 degrees C

• 0 degrees C

• +10 degrees C

• +20 degrees C

To save energy the evaporator temperature in an indoor of an air conditioner for human comfort cooling is:

• +20 degrees C

• -15 degrees C

• +10 degrees C

• -10 degrees C

Which one of the following is likely to damage a compressor?

• High suction superheat

• High subcooling

• Low suction superheat

• Clear oil in the sump sight glass

A TEV phial is disconnected from a suction line would cause?

• High subcooling

• High superheat

• Low superheat

• Flooding back to the compressor