ACTUAL Exam Questions and CORRECT
Answers
(4-113-1.9) The two major types of compression refrigeration systems are: - CORRECT
ANSWER - Indirect and Direct
(4-116-1.4) The safety head of a refrigeration compressor is designed to: - CORRECT
ANSWER - Relieve pressure due to liquid in the cylinder
(4-120-1.2) A pressure relief device on a refrigeration system shall have sufficient capacity to
prevent the pressure in the pressure vessel from rising more than _____ above the setting of the
pressure relief device. - CORRECT ANSWER - 0.1
(4-117-2.1) The amount of water used in an evaporative condenser is only a small percentage of
that used in a water-cooled condenser of the same capacity, because - CORRECT
ANSWER - The cooling water evaporates, removing far more heat per kilogram of system
coolant.
(4-116-int.2) The three main classifications of refrigeration compressors are: - CORRECT
ANSWER - Reciprocating, rotary, and centrifugal
(4-117-2.2) Which of the following statements about double tube refrigeration condensers is
true? - CORRECT ANSWER - Water flows in the inner tube in the opposite direction of
the flow of refrigerant.
(4-114-1.6) Ammonia, as well as being toxic, is also: - CORRECT ANSWER - Flammable
4-117-1.7) All refrigeration evaporators: - CORRECT ANSWER - boil liquid refrigerant
at low pressure and low temperature
, What is the Permissible Exposure Limit for R-717? - CORRECT ANSWER - 50 ppm
(4-116-1.3) Which of the following is NOT considered a rotary refrigeration compressor design?
- CORRECT ANSWER - Centrifugal
(4-123-1.3) In an Ammonia Absorption refrigeration system, what is used as the absorbent? -
CORRECT ANSWER - Water
(4-122-2.1) The safety control of a centrifugal compressor, that ensures the compressor only
starts under a no-load condition, is called the - CORRECT ANSWER - Vane closed switch
(4-123-2.4) The absorber in the lithium bromide refrigeration system is equipped with a pump -
CORRECT ANSWER - To speed the absorption of water vapour
An example of a high leak probability system is a: - CORRECT ANSWER - a direct
expansion system
(4-118-3.2) The low oil pressure cut-off switches of a mechanical refrigeration system -
CORRECT ANSWER - shut down the compressor when the oil pressure drops below the
minimum required value
(4-117-2.4) The refrigeration condenser design that requires chemical cleaning, because it cannot
be mechanically cleaned, is the: - CORRECT ANSWER - Shell and coil condenser
(4-122-2.3) If the chilled water temperature drops approximately 2.5-3°C below the chilled water
temperature set point, the chilled water low temperature cut out will: - CORRECT
ANSWER - Shut down the compressor
(4-122-1.1) Which of the following steps is NOT part of a start-up of a reciprocating or rotary
compressor refrigerating system? - CORRECT ANSWER - Valves in pressure piping
should be closed