One method of controlling the capacity of reciprocating compressors is to bypass the discharge from one or more cylinders back to the suction side of the compressor. The control is called

One method of controlling the capacity of reciprocating compressors is to bypass the discharge from one or more cylinders back to the suction side of the compressor. The control is called

a) compressor unloading
b) damping
c) suction throttling
d) cylinder bypass
e) sectional evaporating






Answer: D

Which of the statements about automatic expansion valves is false?

Which of the statements about automatic expansion valves is false?

a) The valve maintains constant pressure in the evaporator during compressor operation regardless of the load.
b) When the compressor stops the valve automatically shuts off.
c) A spring exerting a downward force on the diaphragm tends to open the valve.
d) The spring force is countered by evaporator pressure acting upward against the diaphragm which closes the valve.
e) The control may be used with multiple cooling coils connected to the same compressor.

Answer: E

A method of controlling the capacity of reciprocating refrigeration compressors, whereby the discharge of high-pressure refrigerant is re-introduced to the suction side of the compressor, is called:

A method of controlling the capacity of reciprocating refrigeration compressors, whereby the discharge of high-pressure refrigerant is re-introduced to the suction side of the compressor, is called:

a. Compressor unloading
b. Cylinder throttling
c. Suction throttling
d. Hot gas bypass
e. Cylinder unloading






Answer: D

The most widely used refrigerant metering device, which consists of a pressure-sensitive bellows or diaphragm connected to a temperature sensing bulb, is a/an:

The most widely used refrigerant metering device, which consists of a pressure-sensitive bellows or diaphragm connected to a temperature sensing bulb, is a/an:

a. Thermostatic expansion valve
b. Automatic expansion valve
c. Capillary tube
d. Equalizer
e. Constant pressure valve






Answer: A

The simple, small-bore device that restricts the flow of liquid from the condenser to the evaporator and maintains a pressure difference between the two, is called:

The simple, small-bore device that restricts the flow of liquid from the condenser to the evaporator and maintains a pressure difference between the two, is called:

a. A high-pressure float valve
b. A low-pressure float valve
c. An equalizer line
d. A capillary tube
e. An intermediate valve (pressure reducing valve)





Answer: D

In a refrigeration system controlled by a high-pressure float valve, excessive refrigerant charge will cause

In a refrigeration system controlled by a high-pressure float valve, excessive refrigerant charge will cause 

a. Liquid carry-over to the compressor
b. The float chamber to become flooded
c. The evaporator to be starved of refrigerant
d. Frost formation on the evaporator
e. The compressor to run continuously






Answer: A