Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. One a psychrometric chart cooling and humidification process using spray can be shown by
a. A line parallel to wet bulb temperature lines
b. A curve
c. A line parallel to dry bulb temperature lines
d. A horizontal line
e. A vertical line
Q. 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
Q. If wet bulb temperature is same as dew point, the relative humidity of air will be
a. 0
b. 25
c. 67
d. 100
e. 50
Q. A plant has one 300 ton and one 500 ton centrifugal unit. The total flow of brine is 6400 litres per minute. What should be the distribution of brine flow through each unit
a. 3200 litres each
b. 2400 litres through 300 ton plant and 4000 litres through 500 ton plant
c. 4000 litres through 300 ton plant and 2400 litres through 500 ton plant
d. Same brine should flow through both
e. None of the above
Q. Which of the following refrigerant has the lowest specific volume?
a. Ammonia
b. Freon 22
c. All the refrigerants have identical specific volume
d. Freon 12
e. Carbondioxide
Q. Which of the following refrigerant compressor is not classified as positive displacement compressor
a. Reciprocating compressor
b. Centrifugal compressor
c. Rotary compressor
d. Screw compressor
e. None of the above
Q. Class II group of refrigerants absorb sensible heat while giving refrigeration effect. Which of the following is a class II refrigerant
a. Ammonia
b. Carbondioxide
c. Freon 12
d. Methyl chloride
e. All of the above
Q. The critical pressure of a liquid is the pressure
a. Below which a liquid will always be in vapour form
b. Above which a liquid will remain a liquid
c. Above which a liquid will always turn into a vapour
d. Above which a liquid will explode
e. None of the above
Q. Frost on cooling coils
a. Increases heat transfer
b. Reduces evaporator temperature
c. Improves COP of the system
d. Acts as an insulation, increasing power consumption
e. Reduces power consumption
Q. The coefficient of performance of a domestic refrigerator as compared to that of an air conditioner is gererally
a. Less
b. Cannot be compared
c. More
d. Air conditioner performance depends on whether conditions
e. Same
Q. The leakage in a refrigeration system using freon is detected by
a. Acetylene torch
b. Halide torch
c. Sulphur stricks
d. Soap and water
e. Any of the above
Q. The critical temperature for Freon 12 is
a. Above 100?C
b. Less than - 50?C
c. Around - 20?C
d. 0?C
e. Around 50?C
Q. In a vapour compression cycle the lowest temperature occurs in
a. Evaporator
b. Expansion valve
c. Condenser
d. Receiver
e. Compressor
Q. If dry bulb temperature is 25?C and wet bulb temperature is 18?C, then which of the following temperatures could possibly represent dew point?
a. 14?C
b. 25?C
c. 40?C
d. 43?C
e. 18?C
Q. 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