How does the receiver ensure that only 100% liquid refrigerant enters the liquid line?
Test?
By means of dip tube.
One use for a low pressure switch is?
Test?
For low charge protection.
A condenser flooding system is sometimes used to provide low ambient temperature operation. To use this method, an extra device must be added to this system. The device is a___?
Test?
Over sized receiver.
To protect the compressor during periods of a hot pull down a __ valve is used.
CPR (crank case pressure regulator)
Refrigeration systems are designed to operate year round. For this reason they are equipped with___?
A low ambient control
Some type of head pressure control.
Random defrost is accomplished how___?
It occurs automatically during the off cycle of the compressor.
When a system pumps down, where is the refrigerant stored?
Receiver
Evaporator
Defrost using internal heat is accomplished using__?
Hot gas from the compressor.
What are some type of low ambient temperature head pressure control?
Pressure controlled dampers in the condenser air stream.
fan cycling
vfd, motormaster controls fan speed
Two temperature operation of a refrigeration system is necessary when__?
More than one evaporator, each at a different temperature, is operating from one compressor.
A hot pull down is when___?
The load on the evaporator produces a suction pressure that increases the load on the compressor.
As the adjusting spring on an evaporator pressure regulator is tightened, the pressure in the evaporator will____?
Increase.
The best way to adjust a CPR valve is by___?
Adjusting the CPR to produce an amperage draw of the compressor motor to the motor name plate rating.
A suction line accumulator is used to reduce the possibility of liquid refrigerant entering the compressor.
True or False
True
An oil separator is installed at the suction intake of the compressor to ensure separation of the refrigerant and oil before entering the compressor.
True or False
False
The crankcase pressure regulator (CPR) puts a limit on the pressure that can return to the compressor
true
Author
salvatorefricano
ID
296773
Card Set
Commercial Refrig. Special Refrig. System Components Chapter 25