Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
the low-pressure side of the system
the high side of the system
the liquid receiver
both a and c are correct
2: What is the minimum height refrigeration piping should be placed against walls?
72"
7.25'
6'
Ceiling height
3: High side floats are used on centrifugal chiller systems are are considered critically charged systems.
are obsolete.
False
depends on the type of refrigerant being used
True
4: The instrument used to measure the specific gravity of absorption chiller solutions is the
hydrometer
anemometer
refractometer
Psychrometer
5: The location of the thermal bulb for the TXV on the evaporator effects
both the pressure and temperature in the feeler bulb
the amount of superheat required to operate the TXV
the amount of liquid in the evaporator
the amount of gas in the evaporator
6: On a single phase motor, when does the start winding cut out?
100% of its RLA speed
50% of its RLA speed
25% of its RLA speed
75% of its RLA speed
7: What is the boiling point of refrigerant governed by?
Compressor RPM's
P&T relationship
Evaporator temperature
Condenser sub-cooling
8: The formula for Pure Power in a resistance circuit is
Watts = volts X amps
Watts X power factor
Kw = volts X amps
Watts X amps.
9: What are the three components of a transformer?
Contacts, secondary coil, and core
Primary coil, secondary coil, and core
Primary core, secondary coil, and high and low voltage connectors.
Primary coil, secondary coil, and copper contacts
10: What must be done to all doors and access points in duct work going through a mechanical room?
Must be hindged
Must be screwed shut
Must be sealed and gasketed
All of the above
11: "R" represents ___ in the Ohm's law formula
resistance
capacitance
amperage
voltage
12: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.
75
100
50
24
13: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?
fusible plug
relief valve
rupture disc
all of the above
14: On cooling towers, what causes the condenser water to drop
tower fans
sensible heat
evaporation of the water droplets
ambient temperatures
15: Liquid level gauges shall have _____________ with one exception being that of the liquid level gauge bull’s eye type.
color-coded glass to determine type of refrigerant
moisture indicators
automatic closing shut-off valves
All of the above
16: In a refrigeration system, you open a valve from the condenser and collect some material on a clean white sheet of bond paper, which of the following would you most likely be testing for?
checking the level of refrigerant in the system
testing for oil in the system
testing for moisture in the system
none of the above
17: Who approves containers for refrigerants?
D.O.T
D.O.E
E.P.A
D.O.D
18: R-22 falls under which safety classification?
B-2
B-1
A-2
A-1
19: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
66.1 psig
43.3 psig
50.2 psig
70.8 psig
20: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are
sight glass, weight, pressure, and dipstick
Buss-eye, weight, pressure, and frost line
sight glass, weight, pressure, and frost line
sight glass, weight, paper method, and frost line.
21: 1 HP = ____ Watts?
746
3.1416
11,239
3,412
22: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?
2%
1%
25%
4%
23: When can 50/50 solder be used?
in the low side
in the high side
liquid and suction lines
none of the above.
24: Refrigerants shall be classified by
maximum permissible quantities of each group
requirements for commercial, industrial, and residential occupancies
color codes
toxicity and flammability
25: Increasing superheat will do what to your system?