Unit 25 - Chapter 115 Flashcards
Raising the condensing point of the refrigerant vapour above the temperature of the cooling medium is a function of the
Compressor
Which of the following are principal parts in a closed cycle compression refrigeration system?
- Evaporator
- compressor
- condenser
Which is not a component of the low pressure side of the system?
Compressor discharge
The temperature in the evaporator
Depends in the pressure in the evaporator
A purpose of a liquid refrigerant control or regulating valve is
To regulate the refrigerant flow to the evaporator
Refrigerant condensers
Cool the gas refrigerant discharged from the compressor
For a direct expansion system which statement is true?
The evaporator can be located in air circulating ducts communicating with the material or space being refrigerated
The primary difference between direct and indirect refrigeration system is the
Evaporator location
Which statement about a system that circulates warm brine or water back to a chiller tank is true?
The evaporator cools the brine or water
The type of brine used for skating or hockey rink refrigeration systems is usually
Calcium chloride
Refrigerant evaporators
May have brine pumped past the coils in an indirect system
Which is not an advantage of a factory assembled packaged refrigerant?
Parts can be ordered and installed separately
Which statement about economizers is false?
Controls the flow of liquid refrigerant from the low pressure evaporator to the high pressure condenser
Which is a result of an economizer on the refrigeration system?
- an inter cooling effect on the compressor
- reduction of the power required for compression in the second stage compressor
- reduction of flash vapour in the evaporator
- increase in the refrigerating capacity of a system
In actual systems there will be a gradual pressure drop through each side of the system due to
Friction in the evaporator, condenser, and piping
What is the term used to describe the device used on a centrifugal chiller to improve efficiency and provide an intercooling effect?
Economizer
Another name for a direct refrigeration system is
A direct expansion system
Which is not an advantage of factory assembled packaged refrigeration units?
The final installation must be according to code
In the evaporator of a refrigeration system
The refrigerant absorbs heat from the surrounding medium
A controlled amount of high temperature high pressure liquid refrigerant
Passes through the regulating valve of the evaporator
The brine pump of a refrigeration system
Circulates the brine through the cooling circuits
Refrigerant condensers
Cool the gas refrigerant discharged from the compressor
