Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
Foot valve
Stop valve
Muffler
Moisture indicator
2: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are
sight glass, weight, paper method, and frost line.
Buss-eye, weight, pressure, and frost line
sight glass, weight, pressure, and dipstick
sight glass, weight, pressure, and frost line
3: How many gallons of water do you need per pound of ammonia?
50
100
10
1
4: What is the minimum size wire you can use on a 30 amp circuit?
10 AWG
16 AWG
14 AWG
12 AWG
5: "P" represents ______ in the Watt's law formula
amperage
watts
voltage
reactance
6: At higher altitudes, the boiling point of refrigerant is
equal to the coefficient of water at 32F
lower
higher
the same
7: How many volts would you read on a 480V system phase to phase?
1/3 the voltage
0
480
277
8: _____ and its alloys are suitable for use with ammonia systems.
Zinc
Aluminum
Copper
Magnesium
9: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
UV or UR
UL and UM
UM or UL
UL and UR
10: Field Inspections of refrigeration and A/C systems in Massachusetts shall be made by
District Engineering Inspectors
Commissioned Inspectors
Master licensed Technician
both a or b
11: While water is evaporated in an evaporative condenser the impurities which were in the water are
accumulate in the sump water
blown to the atmosphere by the fan
washed out of the air by the spray pump
remain in the air
12: 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
13: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is
start the comrpessor
reset the safety valve
reset the expansion valve
start the fan and circulating pump
14: Brazed joints melt at temperatures above
1,000F
500F
1,200F
800F
15: Fusible plugs must have what marked on them?
Melting temperature in F
Melting temperature in C
Opening pressure
All of the above
16: If a refrigerant leaving the condenser is 94F and the condensing temperature is 105F, the subcooling is
21F
9F
29F
11F
17: A pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
50
25
22
66
18: A high side float is a
float type valve that controls the amount of refrigerant stored in the receiver
float type valve that controls the crankcase oil level
metering device used on critically charged systems that controls the level of the liquid refrigerant in the high pressure side of the system.
float type switch that stops the compressor when the pressure on the high side becomes too high
19: What is the temperature that a liquid and a vapor can exist in equilibrium called?
Saturated temperature
Critical temperature
Wet bulb temperature
Dry bulb temperature
20: The gauge thickness required on a CO2 tank construction is
5/16"
1/8"
1/16"
3/32"
21: Capacity control on an absorption system is typically accomplished by varying the
speed of the chilled water circulatory pump
speed of the condenser water circulator pump
rate at which heat is supplied to the generator
pressure setting on the system's rupture disc
22: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
Class B machinery room
Class M machinery room
Class T machinery room
Class A machinery room
23: Whoever owns/uses a refrigeration or air conditioning system covered by this code
must notify the Department of Public Safety prior to starting the system
shall be licensed by the Commonwealth of Massachusetts according to CMR 522
shall make application for inspections to the Chief of Inspectors
None of the above
24: Ammonia (NH3) is a group III refrigerant
True
False
25: When is the only time you can leave a service container attached to a system?