RETA CARO Chapter 2 Exam With Complete
Solutions
Four required components of a mechanical refrigeration system
Expansion device, evaporator, compressor, condenser
Purpose of the Expansion Device
1) To separate the high pressure side of the system and the low pressure side of the system
2) Responsible for metering the proper amount of liquid into the evaporator
Flash Gas
The vapor that results from the expansion process (no practical cooling is done by this item)
Purpose of Evaporator
Absorb heat from the space or product to be cooled
Provides a place for liquid refrigerant to vaporize
Where are saturated conditions found in the refrigeration cycle?
Within the tubes of the evaporator
Purpose of Compressor
1) Receive the vapor that is generated in the evaporator to control the suction pressure within the
evaporator
2) Increase the pressure and temperature of the refrigerant by reducing the volume of the vapor;
moves the suction vapor generated in the evaporator
3) Separates the low side of the system and the high side of the system, moves refrigerant vapor from
the low side of the system to the high side
Low Side Pressure
Found at Compressor Inlet
High Side Pressure
Found at Compressor Outlet
Purpose of Condenser
Reject all of the heat that the refrigerant absorbed into the system
What process is better at absorbing BTUs?
Boiling liquid while changing state (from liquid to vapor)
Ideal refrigeration characteristics
low boiling point and high latent heat of vaporization
Latent Heat of Vaporization
The temperature at which liquid boils is the constant temperature at which it absorbs this
Solutions
Four required components of a mechanical refrigeration system
Expansion device, evaporator, compressor, condenser
Purpose of the Expansion Device
1) To separate the high pressure side of the system and the low pressure side of the system
2) Responsible for metering the proper amount of liquid into the evaporator
Flash Gas
The vapor that results from the expansion process (no practical cooling is done by this item)
Purpose of Evaporator
Absorb heat from the space or product to be cooled
Provides a place for liquid refrigerant to vaporize
Where are saturated conditions found in the refrigeration cycle?
Within the tubes of the evaporator
Purpose of Compressor
1) Receive the vapor that is generated in the evaporator to control the suction pressure within the
evaporator
2) Increase the pressure and temperature of the refrigerant by reducing the volume of the vapor;
moves the suction vapor generated in the evaporator
3) Separates the low side of the system and the high side of the system, moves refrigerant vapor from
the low side of the system to the high side
Low Side Pressure
Found at Compressor Inlet
High Side Pressure
Found at Compressor Outlet
Purpose of Condenser
Reject all of the heat that the refrigerant absorbed into the system
What process is better at absorbing BTUs?
Boiling liquid while changing state (from liquid to vapor)
Ideal refrigeration characteristics
low boiling point and high latent heat of vaporization
Latent Heat of Vaporization
The temperature at which liquid boils is the constant temperature at which it absorbs this
