Exam 23: Compressors

Excessive heat and pressure on the oil in a compressor can cause oil to break down and cause the formation of ____________________ and acid.

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

The sight glass on a semihermetic compressor is used to allow light to enter the crankcase to keep the oil warm .

____________________ is a bimetallic disc that senses compressor discharge temperature and opens at 270ºF.

____________________ opens at approximately 400 ± 50 psi differential between high- and low-side pressures for R-22, and at a 500 to 625 psi differential for R-410A.

The higher the rpm of a compressor, the higher the pumping efficiency.

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

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

The compression ratio for an R-22 compressor operating with 68.5 psig suction pressure and 260 psig heat pressure is ____________________.

Rotary compressors have pistons that rotate inside the cylinders.

The screw compressor is used primarily in ____.

The space at the top of the cylinder when the piston reaches the top of its stroke is called ____________________.

Scroll compressors are becoming popular because they can handle liquid floodback without compressor damage.

Why can't reciprocating compressors pump liquid?

When the piston reaches the bottom of its stroke, it is called ____________________.

A compressor that has the motor and compressor in a housing that is bolted together is called a(n) ____________________ type.

The clearance volume of a compressor cylinder is the ____.

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

Explain when the compressor's lubrication system is fully effective.

A decrease in suction pressure will have what effect on a reciprocating compressor?