Unit 23: Compressors QUIZ (CRF)-Mr.Graham

Which of the following best describes the function of a compressor?

• The compressor restricts the flow of refrigerant that enters the evaporator.

• The compressor pumps liquid refrigerant into the condenser to transfer heat.

• The compressor is used to throttle a thermostatic expansion valve (TXV) open or closed.

• The compressor increases the pressure in the system from the low-side pressure to the high-side pressure.

Five types of compressors are _____________.

• rotating, analog, scroll, screw, and binary

• reciprocating, rotary, scroll, screw, and centrifugal

• bolted, screw, scroll, binary, and centrifugal

• belt-drive, direct-drive, rotating, binary, and scroll

Which of the following is true of HVACR compressors?

• A compressor cannot compress a liquid.

• A compressor can compress a liquid.

• A compressor requires liquid refrigerant for lubrication.

• A compressor takes in vapor and discharges liquid.

What would be considered a higher-than-normal temperature for a discharge gas line on a reciprocating compressor?

• 190°F

• 200°F

• 250°F

• 175°F

Which compressor type uses pistons to compress the gas?

• Scroll

• Reciprocating

• Rotary

• Screw

Which compressor type uses tapered, machined gear components to trap the gas for compression?

• Scroll

• Reciprocating

• Rotary

• Screw

Which style of compressor uses belts to turn the compressor?

• Open drive

• Closed drive

• Chassis drive

• Hermetic drive

What would be done to increase the compressor speed on a belt-driven compressor?

• Decrease drive pulley size

• Increase drive pulley size

• Increase driven pulley size

• Both A and C

A medium-temperature R-134a system that has a suction pressure of 22 psig and a discharge pressure of 185 psig would have a compression ratio of _________.

• 8.40 to 1

• 5.44 to 1

• 10.1 to 1

• 13.89 to 1

A direct-drive compressor typically runs at _______ rpm. a. 1750 or 3450 b. 3450 or 4500 c. 17,500 or 34,500 d. 1800 or 4800

• 1750 or 3450

• 3450 or 4500

• 17,500 or 34,500

• 1800 or 4800