Multiple Choice Questions (MCQ) with answers on Refrigeration and Air conditioning

21-The process in winter air conditioning is

(A) Dehumidification

(B) Heating and humidification

(C) Humidification

(D) Cooling and dehumidification


22-A thermostatic expansion valve function with

(A) suction pressure

(B) discharge pressure

(C) discharge temperature

(D) suction temperature


23-The colour of the flame of halide torch in case of leakage of Freon refrigerant will change t:

(A) Purple

(B) Pink

(C) Bright green

(D) Blue


24-Liquid charged in thermostatic expansion valves sensing bulb is:

(A) alcohol

(B) same refrigerant

(C) mercury

(D) nitrogen


25-The oil used with 134A refrigerant is:

(A) Mineral oil

(B) Capilla D

(C) Polyol ester oil

(D) Lubricating oil


26-The difference between DBT and WBT is called:

(A) wet bulb depression

(B) dew point depression

(C) effective temperature

(D) adiabatic saturation temperature


27-A device which is used to find relative humidity:

(A) Pyrometer

(B) Anemometer

(C) Hydrometer

(D) Hygrometer


28-Which type of valve is used in a reciprocating refrigeration compressor?

(A) rotary valve

(B) poppet valve

(C) ring plate

(D) glob valve


29-The capacity of visible cooler is expressed in:

(A) cubic feet

(B) litres


(D) tons of refrigeration


30-Chemical name of Freon 22 is

(A) Dichloro difluoro methane

(B) Monochloro difluoro methane

(C) Trichloro monofluoro methane

(D) Dichloro monofluoro methane



21-(B), 22-(A), 23-(C), 24-(B), 25-(C), 26-(A), 27-(D), 28-(B), 29-(B), 30-(B)