Air Conditioning Repair Refrigeration System Repair 2

Question 1

A technician measures suction pressure that is too high and discharge pressure that is too low. What is the most likely cause?

Accepted Answer

Faulty compressor valves

Answer

Faulty compressor valves (worn or leaking) allow high-pressure gas to bypass back to the suction side, raising suction pressure and lowering discharge pressure.

Question 2

Which refrigerant is classified as an A2L (mildly flammable) and is commonly used as a replacement for R-22 in new equipment?

Accepted Answer

R-32

Answer

R-32 is classified as A2L (mildly flammable) and is increasingly used in new equipment as an environmentally preferable alternative.

Question 3

When replacing a filter-drier on a refrigeration system, what is the correct procedure after installing the new drier?

Accepted Answer

Pull a deep vacuum before recharging

Answer

After replacing a filter-drier, a deep vacuum must be pulled to remove air and moisture before recharging with refrigerant.

Question 4

A refrigerant sight glass shows bubbles even though the system appears to have adequate charge. What could cause this besides low charge?

Accepted Answer

Pressure drop across a restriction in the liquid line

Answer

A restriction in the liquid line causes a pressure drop that can flash refrigerant into vapor, producing bubbles in the sight glass even with sufficient charge.

Question 5

What is the purpose of a suction line accumulator in a refrigeration system?

Accepted Answer

Prevent liquid refrigerant from entering the compressor

Answer

A suction line accumulator catches any liquid refrigerant before it can reach the compressor, protecting it from liquid slugging damage.

Air Conditioning Repair Practice Test

Air Conditioning Repair Practice Test

Air Conditioning Repair Refrigeration System Repair 2