In control cooling water system, chromates, phosphates and silicates are added to water
A.To prevent scale formation
B.To remove odour
C.To increase remove foreign particle
D.To inhibit corrosion
E.To prevent algae growth
Category: Refrigeration and Air conditioning Mcqs
If a discharge pressure of a refrigeration compressor is too high, it shows there is (are)
A.Too little or too warm condenser water
B.Fouled tubes in shell and tube condenser
C.Improper operations of evaporator condenser
D.Overcharge of refrigerant
E.Any of the above
For for measurement of temperature in cryogenic range the thermometers used are
A.Pyrometers
B.Radiation pyrometers
C.Mercury thermometers
D.Gas thermometers
E.Electronic digital instruments
A prssure gauge on the discharge side of compressor
A.Indicates the temperature of refrigerant after compression
B.Gives an ideas about the coefficient of performance of the cycle
C.Gives a warning when the pressure reaches a dangerous point
D.Confirms the flow of refrigerant in cycle
E.Is mounted for show only
The performance of an evaporative condenser largely depends on
A.Dry bulb temperature
B.Wet bulb temperature
C.Hot water temperature
D.Ambient temperature
E.Air conditioned room temperature
Freon 12 is a compound consisting of stoms of
A.Carbon, hydrogen and fluorine
B.Carbon, hydrogen and oxygen
C.Carbon, hydrogen, fluorine and chlorine
D.Carbon, fluorine and chlorine
E.Carbon and hydrogen
In a vapour compression cycle the refrigerant immediately after expansion valve is in
A.Liquid form
B.Wet vapour form
C.Dry vapour form
D.Dry and saturated vapour form
E.None of the above
Brine is always used as a secondary refrigerant in
A.Cold storage plant
B.Milk chilling plant
C.Cinema hall air conditioning plants
D.Ice plant
E.All of the above
The effect of under cooling the refrigerant is to
A.Reducing the COP of the cycle
B.Increase the COP of the cycle
C.Reduce the refrigerating effect
D.Increase the super heat of vapour
E.None of the above
Sometimes refrigeration plants use cooling towers. The water cooled in those towers is supplied
A.For defrosting evaporator coils
B.To cool compressor cylinder only
C.To cool refrigerant in evaporator
D.To cool refrigerant in condenser
E.None of the above
