ACR-104 Unit 23

If the compression ratio of a system with a reciprocating compressor decreases, the amount of refrigerant pumped by the compressor ____.

• will increase
• will decrease
• will remain the same
• cannot be determined

Most of the heat energy in the suction vapor entering the compressor is ____.

• superheated from the evaporator
• subcooled from the condenser
• superheated from the condenser
• subcooled from the evaporator

The temperature of the compressed gas leaving the compressor can best be described as ____.

• hot

• cold
• cool
• warm

The screw compressor is used primarily in ____.

• large commercial and industrial systems
• residential air conditioning
• small commercial refrigeration units
• domestic refrigerators

Rotary compressors are used primarily in ____.

• residential and light commercial air-conditioning
• large industrial refrigeration and air conditioning systems
• small commercial refrigeration units
• high volume residential refrigeration

The clearance volume of a compressor cylinder is the ____.

• volume of the space between the bottom of the valve plate and the top of the piston at the top of the stroke
• amount of refrigerant vapor the compressor cylinder will hold during each stroke
• volume by which the compressor is rated
• total volume of the cylinder when the piston is at the bottom dead-center

The discus valve design is more efficient than a flapper valve design because ____.

• it allows a compressor design with less clearance volume
• it operates with less spring tension
• the amount of expanded vapor in the cylinder is greater
• it will not allow liquid refrigerant in the cylinder

Liquid entering the compression chamber of a reciprocating compressor can lead to ____.

• Both
• damaged valves
• damaged piston rings
• none

Rotary compressors have pistons that rotate inside the cylinders.

• False
• True

The rotary screw compressor uses an open motor instead of the hermetic design.

• True
• False