Answered | Graded A+
the efficiency of the refrigerant cycle is affected by the operation of the condenser. Of the following, a
more efficient centrifugal compressor operation results from - ANSWER-lowering the condenser
pressure
In most semi hermetic compressors, the suction vapor is used for - ANSWER-cools the motor
The amount of refrigerant that flows through the orifices of an economizer is determined by the -
ANSWER-difference between the high side and the low side pressure
the instalation of an inline refrigerant cleaning system is advisable - ANSWER-to remove impurities from
the system
a refrigerant engineer verifies that a condenser pump is cavitation of the following the most likely cause
for this condition is: - ANSWER-a faulty cooling tower water level controller
when an expansion valve is operating properly, at the end of the evaporator will contain - ANSWER-only
superheated vapor
a centrifugal water pump is considered to be fully primed when - ANSWER-the pump is full of liquid
A refrigeration compressor has failed to turn on. the engineer on duty verifies the electrical circuit to the
motor, including all switches and circuit breakers is complete, according to recomended service practice,
the next item to be checked would likely be the: - ANSWER-temperature and pressure controls
Refrigerants are characterized by their physical properties including Flashpoint, refrigeration effect and
others, of the refrigerants in commercial and industrial the highest latent heat and refrigerant effect is: -
ANSWER-ammonia
which of the following ashrae refrigerant safety classification is the most toxic - ANSWER-b3
, which of the following ashrae refrigerant safety classification is the most flammable - ANSWER-a3
in q indirect refrigeration system,of the following, the one that would not be used as a cooling medium
for building spaces being cooled is - ANSWER-r 22 (cooling medium= glycol or any brine solution)
the primary way of achieving capacity control of a an centrifugal compressor is by: - ANSWER-
adjustment to the inlet impeller pre rotation vanes
regarding the functioning of a steam turbine, why is it advisable to keep moisture in the inlet low as
possible - ANSWER-keeps turbine blades wear to minimum
a water chiller is equipped with a reciprocating compressor, a thermostatic expansion valve and a an air
cooled condenser. A restriction in the refrigerant line would result in - ANSWER-high suction super heat
the process by which refrigerant is extracted and cleaned for reuse without requirements for
reclamation is called - ANSWER-recycle
the purpose of wear rings in a centrifugal pump is to - ANSWER-prevent wearing of the pump housing
and impeller
a centrifugal compressor is in operation with suction pressure is 3 psig and the discharge is 10psi what is
the atmospheric pressure is 14.7 which is the ratio closest to - ANSWER-1.39
electrical current us measured in - ANSWER-amperage
how would you put an additional pump online - ANSWER-open suction valve, open discharge valve
gradually
of the following, the major advantage of a shell and coil condenser is - ANSWER-there is less danger of
developing leaks