Refrigeration Exam 1 ALL QUESTIONS AND CORRECT ANSWERS LATEST UPDATE THIS YEAR

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Refrigeration Exam 1 ALL QUESTIONS AND
CORRECT ANSWERS LATEST UPDATE THIS
YEAR
QUESTION: the type of refrigerant system that is least likely to leak refrigerant into the building

space that are being cooled: - ANSWER-the indirect system




QUESTION: the suction pressure of a reciprocating compressor is 65 PSIG. The discharge

pressure of this compressor is 120 PSIG. The atmospheric is 14.7 PSI. the compression ratio for

the given condition is closest to: - ANSWER-1.69




QUESTION: a superheated vapor is: - ANSWER-dry vapor above the saturation temperature




QUESTION: a refrigerant engineer veritifies that a condenser water pump is cavitating. Of the

following, the most likely cause for this condition is: - ANSWER-a faulty cooling tower water

level controller




QUESTION: a centrifugal water pump is known as a lift pump when the: - ANSWER-the water

supply to the pump suction inlet is below the pump level


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QUESTION: a TXV is used to maintain constant: - ANSWER-evaporator superheat




QUESTION: the chilled water supply to the building is 55F. If the chiller is being used for human

comfort, should you be concerned about this, and why? - ANSWER-Yes, this temp is too high for

human comfort purpose




QUESTION: the packing gland of a centrifugal pump serves to: - ANSWER-the drip part of the

packing gland gives evidence that there is water in the pump




QUESTION: capacity control of reciprocating hermetic compressor is typically achieved through

- ANSWER-operation of the hot gas bypass valve




QUESTION: the most important reason to sub-cool the refrigerant in the condenser is to ensure

that: - ANSWER-a pure liquid refrigerant will enter the metering device




QUESTION: A refrigeration engineer is logging readings from a reciprocating system.

Compressor discharge temperature have dropped significantly and the suction line pressure is


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high. Which of the following that may be causing this set of condition? - ANSWER-an expansion

valve that is open to wide




QUESTION: a low side float valve is used to maintain: - ANSWER-the level of the refrigerant in

the evaporator




QUESTION: regarding fire safety, which ASHRAE refrigerant safety classification indicates no

flammability and lower toxicity? - ANSWER-A1




QUESTION: when an expansion valve is operating properly, at the end of the evaporator will

contain: - ANSWER-only superheated vapor




Q; efficiency of the refrigerant cycle is affected by the operations of the condenser. Of the

following, a more efficient centrifugal compressor operation results from: - ANSWER-Lowering

the condensing pressure




QUESTION: The heat removed from the refrigerant in a condenser is: - ANSWER-sensible and

latent heat



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QUESTION: The refrigerant unit that you have been assigned to is being taken out of service for

a major repair. You have been assigned to withdraw refrigerant for storage in suitable

containers. According to the NYC fire code, you must ensure that the containers: - ANSWER-Are

approved by the US Dept. of Transportation




QUESTION: which of the following best describes how the cylinder unloader work? - ANSWER-

keep in the suction valve opened while the compressor is in the return stroke




QUESTION: in most semi Hermetic compressors, the suction vapor is used to: - ANSWER-cools

the motor




QUESTION: The amount of refrigerant that flows through the orifices of an economizer is

determined by the: - ANSWER-differences between the high side and low side pressure




QUESTION: the installation of an inline refrigerant cleaning system is advisable: - ANSWER-to

remove impurities from the system




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