QUESTIONS AND CORRECT ANSWERS
When making repairs to an R-22 system, prior to brazing, you should ___? - CORRECT
ANSWER Ensure that the flame is enclosed and vented to the open air
If the oil level in a refrigeration system is low, additional oil should be ___? - CORRECT
ANSWER Pumped it into the compressor crankcase
The device pictured below is a ___? - CORRECT ANSWER Purge unit
What will make the strong liquor in an absorption system weaker? - CORRECT
ANSWER Less load on the evaporator
Which material is suitable for a methyl chloride system? - CORRECT
ANSWER Copper
Which method can be used to determine if a pressure gauge is providing an accurate reading?
- CORRECT ANSWER Open it to atmosphere and confirm that is reading zero psi
How is a system affected if an unloader leaks? - CORRECT ANSWER Compressor
capacity will reduce
If the capillary line of a thermostatic expansion valve is ruptured, the expansion valve will
___? - CORRECT ANSWER Remain fully closed
How many gallons of water are there in a container with a volume of 8085 cubic inches? -
CORRECT ANSWER 35
Which electrical component is needed to reduce a 120 volt power source to 24 volts? -
CORRECT ANSWER Transformers
, When chilled water is circulated as the cooling medium, the saturation pressure of the
evaporator can be used to estimate the ___? - CORRECT ANSWER Chilled water
temperature being pumped into the building being served
Purgers are most often used with systems that operate ___? - CORRECT
ANSWER Below 14.7 psia
A pipe 1" in diameter and 285' long, weighs 650 lbs when empty. How much does it weigh
when it is full of water? - CORRECT ANSWER 750 lbs.
A thermostatic expansion valve regulates ___? - CORRECT ANSWER Flow of
refrigerant to the evaporator
The amount of refrigerant that flows through an orifice plate is determined by ___? -
CORRECT ANSWER Difference in pressure between the high side and low side
Which substance is not used as a cooling medium in an indirect system? - CORRECT
ANSWER R-22
The properties of a good refrigerant oil include __? - CORRECT ANSWER Non-
corrosive and harmless quality to metals
Non-condensables in a system can cause ___? - CORRECT ANSWER High condenser
pressure
Which can cause high suction pressure, under normal conditions? - CORRECT
ANSWER TEV wide open
The function of a cylinder bypass valve is to ___? - CORRECT ANSWER Allow
operation at different capacities