Study Guide with Complete
Solutions
The evaporator in a refrigeration system must be colder Than the refrigerated space
in order to absorb heat. - ANSWER - True
The rule of thumb for low temperature refrigeration is 5 degrees superheat. -
ANSWER - True
Capillary tube systems are normally used for storage of already refrigerated
products. - ANSWER - True
Fewer fins per inch on an evaporator allows more ice to build between defrost
cycles. - ANSWER - True
Multiple circuit evaporator uses an externally equalized expansion valve. - ANSWER
- True
Refrigerants that boil off at different rates are called zeotropic blends. - ANSWER -
True
R-22 is considered a low pressure refrigerant. - ANSWER - False
High superheat means your TXV is flooding the coil. - ANSWER - False
The fastest defrost method is hot gas defrost. - ANSWER - True
Hot gas and electric defrost use the same time clock. - ANSWER - True
, If you are a refrigeration technician, a warm coat, hat and gloves should be in your
truck even in the middle of the summer. - ANSWER - True
The voltage that opens the point of a potential real is called the drop-out voltage. -
ANSWER - True
Good ventilation is important when working around refrigeration equipment
because modern refrigerants ______________ . - ANSWER - Are heavier than air and
may displace the oxygen around you
A thermostatic expansion valve controls refrigerant flow to the evaporator based on
____________ . - ANSWER - Rate of liquid vaporization, evaporator suction line
superheat, and external equalizer pressure.
The start capacitor is wired in series with the start relay. - ANSWER - True
Walk-in box temperature box is not needed when calculating the TD of an
evaporator coil. - ANSWER - False
The contacts in a current type starting relay are normally closed. - ANSWER - False
A motor can burn-out if the supply voltage is either too high or too low. - ANSWER -
True
A run capacitor helps a compressor run efficiently by slightly energizing the start
winding. - ANSWER - True
The suction and discharge valves in a reciprocating compressor open and close
depending on the difference in pressure across them. - ANSWER - True
When setting a fan cycle switch, you should set the cut-out to a pressure equivalent
to 90 degrees condensing temperature. - ANSWER - True