Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. When Freon 12 is the refrigerant, the condenser and evaporator cables are made of
a. Aluminium
b. Cast iron
c. Steel
d. Copper
e. Wrought iron
Q. In vapour absorption system using ammonia, water is required for
a. Absorber only
b. Separator only
c. Condenser, absorber and separator
d. Condenser only
e. Condenser and absorber
Q. The ratio of mass of water vapour associated with unit mass of dry air to the mass of water vapour associated with unit mass of dry air saturated at the same temperature is known as
a. Relative humidity
b. Specific humidity decreases
c. Humidity ratio
d. Degree of saturation
e. None of the above
Q. In a refrigerator system if compressor fails to operate, the probable reason could be
a. Power failure
b. Low voltage
c. Burnt motor
d. Fuse blown
e. Any of the above
Q. A thermometer in vapour compression system is installed in the main line close to the compressor
a. As it helps the operator to adjust compressor for greatest efficiency
b. As temperature indicates whether liquid or vapour refrigerant is going to compressor
c. As temperature helps in calculating the coefficient of performance
d. As the performance of other units of the cycle can be controlled
e. None of the above
Q. White ice is
a. Sub-cooled water
b. Fast cooled water
c. Due to dissolved air, gases and impurities
d. Produced by blowing air during freezing
e. None of the above
Q. In which type of single phase motor the starting torque is low
a. Capacitor start type
b. Shaded pole type
c. Starting torque is same in all motors
d. Permanent split capacitor type
e. Capacitor start and capacitor run type
Q. Air conditioning means
a. All above
b. Removal of air impurities
c. Heating
d. Dehumidifying
e. Cooling
Q. Dew points temperature is an indication of
a. Moisture content of air
b. Dryness of air
c. Lowest temperature where air and water vapour start separating
d. Condition air
e. Any of the above
Q. The most common type of vapour absorption system in use for industrial application is
a. Hydrogen and water
b. Freon 22 and water
c. Brine and water
d. Freon 12 and water
e. Ammonia and water
Q. Brazing is the process used for joining
a. Two ferrous materials
b. One ferrous and one non-ferrous material
c. Two non-ferrous materials
d. Two non-metals
e. None of the above
Q. Of the following chemicals the liquid having the greatest cooling effect on an individual is
a. Water
b. Water containing ammonium hydroxide
c. Ether
d. Alcohol
e. Brine
Q. In vapour absorption system the function of rectifier is
a. To cool the vapour leaving the analyzer
b. To separate ammonia and water
c. To dissolve ammonia in water
d. To add energy from external source
e. None of the above
Q. 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
Q. When moisture is added to air at constant dry bulb temperature, the process is known as
a. Humidification
b. Sensible cooling
c. Wetting
d. Chilling
e. None of the above