Topics: All categories in the pool
1: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
2: The outer portion of shell of the compressor used on low-pressure chillers is called the
- volute
- baffle
- nozzle
- suction
3: R-22 is classified as a ____ refrigerant on the safety matrix.
- B-2
- A-1
- B-1
- A-2
4: Pi equals approximately
- 746
- 3.41
- 12,000
- 3.14
5: The density of a gas refers to
- pounds per square foot
- pounds per cubic foot
- cubic feet per pound
- pounds per absolute pressure
6: Name a CFC refrigerant(s):
- R-11
- R-12
- R-123
- both a & b
7: Class T machine room
- shall have refrigerant leak detecting systems installed inside and outside the room
- has no flame producing apparatus permanently installed
- shall include closets used for setting equipment
- shall have remote controls to stop the action of the refrigerant compressor
8: R-123 belongs to Group
- B-1
- B-3
- A-3
- B-2
9: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the
- low side of the system
- high side float assembly
- cap tube
- none of the above
10: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.
- 25
- 20
- 10
- 15
11: Evaporators located ____inches of a heating coil shall be equipped whit a pressure relief device.
- 15
- 10
- 24
- 18
12: High pressure controls should be set no higher than
- 10% of set point
- 25% of set point
- 90% of set point
- 80% of set point
13: Heat is a form of
- energy
- work
- power
- matter
14: The gauge thickness required on a CO2 tank construction is
- 1/8"
- 5/16"
- 1/16"
- 3/32"
15: When a refrigerating machinery room is used, the emergency procedures shall be posted
- inside the room, immediately adjacent to each door
- on a conspicuous card located near the compressor
- outside the room, immediately adjacent to each door
- on a conspicuous card located near the evaporator
16: A high side float is a
- 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 valve that controls the crankcase oil level
- float type valve that controls the amount of refrigerant stored in the receiver
- float type switch that stops the compressor when the pressure on the high side becomes too high
17: Pressure vessels of 10 cubic feet or more gross volume shall use
- at least one rupture member
- a dual pressure-relief valve if charging into the atmosphere
- at least three means of discharge and/or rupture discs
- both a and b are correct
18: A start capacitor in series with a start winding will
- decrease the amp draw of the motor
- increase running efficiency
- increase starting torque
- increase the amp draw of the motor
19: A direct system
- is on where brine is cooled & circulated to the space refrigerated
- is one which encloses a separate body of evaporative refrigerant
- is where the refrigerant comes in contact with the space refrigerated
- is a self-contained complete factory made and tested system
20: Pressure vessels with an internal volume of 3 cubic feet or less
- shall use pressure relief devices
- do not need pressure relief protection
- shall use pressure relief devices or fusible plugs
- shall use fusible plugs
21: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 50
- 22
- 33
- 18
22: Color is important in oil because
- it makes sight glasses easy to read
- allows you to see into crankcase
- can tell us something about the refining of oil
- it indicates the viscoisty.
23: Class 3 refrigerants are
- non-toxic
- toxic
- non-flammable
- highly flammable
24: An air conditioning system rated for 36,000 BTU's is equivalent to
- two tons of cooling
- one ton of cooling
- 12,000 tons of cooling
- three tons of cooling
25: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.
- high pressure
- low pressure
- critical pressure
- design pressure