Refrigeration Exam Questions
and Answers
A refrigeration system circulates warm brine back to a chiller. Which of the following
statements about this system is true?
The condenser in the system is located in direct contact with the material being
refrigerated.
The evaporator in the system is located in direct contact with the material being
refrigerated.
The brine or water is the refrigerant.
The evaporator cools the brine.
The system is a direct refrigeration system. - Answer- The evaporator cools the brine.
The temperature in the evaporator:
Depends on pressure in the receiver.
Will decrease when the compressor stops.
Depends on pressure in the evaporator.
Depends on the ambient temperature.
Is controlled by the charging valve. - Answer- Depends on pressure in the evaporator.
With regard to economizers installed on packaged air-conditioning chillers, which of the
following statements is false?
Economizers control the flow of liquid refrigerant from the evaporator to the condenser.
Liquid refrigerant levels in each chamber are controlled by float operated, valves.
The upper float chamber is connected to the bottom of the condenser.
,The economizer float chamber is connected via the motor to the second stage inlet of
the compressor.
It is composed of two chambers. - Answer- Economizers control the flow of liquid
refrigerant from the evaporator to the condenser.
A compression refrigeration system can be divided into two parts; a high pressure
section carrying the head pressure and a low pressure section carrying the _____
pressure:
Discharge
Back
Hot
Return
Suction - Answer- Suction
Which of the following statements about double tube refrigeration condensers is true?
They consist of two separate tubes side by side.
They are easy to clean.
Water flows in the inner tube in the opposite direction of the flow of refrigerant.
They have the highest efficiency of the water-cooled condensers.
They have a large cooling capacity combined with a small size. - Answer- Water flows in
the inner tube in the opposite direction of the flow of refrigerant.
The amount of heat absorbed by water when it evaporates at atmospheric pressure is:
99.63 kJ/kg
335 kJ/kg
417.46 kJ/kg
2257 kJ/kg
2675.5 kJ/kg - Answer- 2257 kJ/kg
, With regard to refrigeration systems, large-capacity air-cooled condensers are found
mainly:
On roof tops.
In indoor mechanical rooms, with ductwork supplying cooling air.
In locations where water is plentiful.
Where they are protected from the environment.
In systems where the high-side pressure does not exceed 103 kPa. - Answer- On roof
tops.
The refrigeration evaporator that increases heat exchange by crimping several thin
metal plates to single-wall tubes is a:
Plate surface evaporator
Bare tube evaporator
Shell and tube evaporator
Finned tube evaporator
Double tube - Answer- Finned tube evaporator
The amount of water used in the evaporative condenser of a refrigeration plant is only a
small percentage of that used in a water condenser of the same capacity, because:
Evaporating condensers also use air to cool the refrigerant.
The evaporating condensers spray refrigerated water onto condensing coil.
The cooling water evaporates, removing far more heat per kilogram of system coolant.
Of water conservation methods.
Of the scarcity of water in locations that use evaporative condensers. - Answer- The
cooling water evaporates, removing far more heat per kilogram of system coolant
In a refrigeration system, which of the following is NOT a cause of poor condenser
performance?
Waterside scale accumulation.
and Answers
A refrigeration system circulates warm brine back to a chiller. Which of the following
statements about this system is true?
The condenser in the system is located in direct contact with the material being
refrigerated.
The evaporator in the system is located in direct contact with the material being
refrigerated.
The brine or water is the refrigerant.
The evaporator cools the brine.
The system is a direct refrigeration system. - Answer- The evaporator cools the brine.
The temperature in the evaporator:
Depends on pressure in the receiver.
Will decrease when the compressor stops.
Depends on pressure in the evaporator.
Depends on the ambient temperature.
Is controlled by the charging valve. - Answer- Depends on pressure in the evaporator.
With regard to economizers installed on packaged air-conditioning chillers, which of the
following statements is false?
Economizers control the flow of liquid refrigerant from the evaporator to the condenser.
Liquid refrigerant levels in each chamber are controlled by float operated, valves.
The upper float chamber is connected to the bottom of the condenser.
,The economizer float chamber is connected via the motor to the second stage inlet of
the compressor.
It is composed of two chambers. - Answer- Economizers control the flow of liquid
refrigerant from the evaporator to the condenser.
A compression refrigeration system can be divided into two parts; a high pressure
section carrying the head pressure and a low pressure section carrying the _____
pressure:
Discharge
Back
Hot
Return
Suction - Answer- Suction
Which of the following statements about double tube refrigeration condensers is true?
They consist of two separate tubes side by side.
They are easy to clean.
Water flows in the inner tube in the opposite direction of the flow of refrigerant.
They have the highest efficiency of the water-cooled condensers.
They have a large cooling capacity combined with a small size. - Answer- Water flows in
the inner tube in the opposite direction of the flow of refrigerant.
The amount of heat absorbed by water when it evaporates at atmospheric pressure is:
99.63 kJ/kg
335 kJ/kg
417.46 kJ/kg
2257 kJ/kg
2675.5 kJ/kg - Answer- 2257 kJ/kg
, With regard to refrigeration systems, large-capacity air-cooled condensers are found
mainly:
On roof tops.
In indoor mechanical rooms, with ductwork supplying cooling air.
In locations where water is plentiful.
Where they are protected from the environment.
In systems where the high-side pressure does not exceed 103 kPa. - Answer- On roof
tops.
The refrigeration evaporator that increases heat exchange by crimping several thin
metal plates to single-wall tubes is a:
Plate surface evaporator
Bare tube evaporator
Shell and tube evaporator
Finned tube evaporator
Double tube - Answer- Finned tube evaporator
The amount of water used in the evaporative condenser of a refrigeration plant is only a
small percentage of that used in a water condenser of the same capacity, because:
Evaporating condensers also use air to cool the refrigerant.
The evaporating condensers spray refrigerated water onto condensing coil.
The cooling water evaporates, removing far more heat per kilogram of system coolant.
Of water conservation methods.
Of the scarcity of water in locations that use evaporative condensers. - Answer- The
cooling water evaporates, removing far more heat per kilogram of system coolant
In a refrigeration system, which of the following is NOT a cause of poor condenser
performance?
Waterside scale accumulation.
