Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: Which of the following types of oils are hygroscopic?
polyolester (POE)
polyalkylene glycol (PAG)
naphthene mineral
both a and b
2: Fusible plugs shall not be used with pressure vessels of
3 cubic feet or less
15 square feet or less
15 cubic feet or more
3 cubic feet or more
3: When is the only time you can leave a service container attached to a system?
Leaking system
Recovery
Charging
Both b and c
4: 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
24
100
50
5: The certificate of inspection
shall be posted and protected from dirt, water, and other elements
shall be posted on the compressor shell or electrical panel at the unit
shall be $20 and an additional fee of $1 for each tone above 20 tons
shall be authorized by a notarized insurance company
6: What refrigerant is an inorganic compound?
R-132A
R-410A
R-22
Ammonia
7: Heat transferred by conduction from one body to another is done
via heat rays
via radiation
via liquids
via solids
8: Joints in refrigeration piping must be _____ before being covered?
Leak tested
Insulated
Pressurized
Inspected
9: When a refrigerating machinery room is used, the emergency procedures shall be posted
on a conspicuous card located near the compressor
on a conspicuous card located near the evaporator
inside the room, immediately adjacent to each door
outside the room, immediately adjacent to each door
10: When can 50/50 solder be used?
in the low side
in the high side
liquid and suction lines
none of the above.
11: A class B1 refrigerant is considered
non-toxic but highly flammable
non-toxic and non-flammable
toxic but non-flammable
toxic and somewhat flammable
12: Which refrigerant class listed below is the most flammable?
A-1
A-3
C-3
B-2
13: When using nitrogen for brazing, the pressure should be:
Very low
50-100 psig
125 psig
Slightly below atmospheric
14: A run capacitor is wired in series with the _____ windings.
run
start
start capacitor
common
15: Evaporators located ____inches of a heating coil shall be equipped whit a pressure relief device.
10
24
18
15
16: Suction valve unloaders afford an effective means of
capacity control
superheat control
evaporator control
refrigerant control
17: Copper and its alloys shall not be used with ammonia
True
False
18: When is the space above a drop ceiling calculated as space for refrigerant limit quantities?
When it's used as part of a supply or return air system
When there is a space 6' or more above it
When there are sprinklers above
When its white
19: What would be the classification for Stop & Shop grocery store?
Large mercantile
Place of assembly
Industrial
Instituional
20: RPM's of a centrifugal compressor are at approximately?
30,000
500
15,000
10,000
21: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
2.5
There isn't enough information to answer.
1250
2
22: When systems are protected by a high pressure relief device, the compressor's pressure limiting device shall be set at or below ____ % of the operating pressure of the high side relief device.
110
80
100
90
23: Where are the three places that the discharge from an ammonia relief valve be piped?
atmosphere, tank containing water, where the A.H.J. indicates
underground, into drain, into mechanical room
to chemical neutralizing tank only
none of the above
24: 746 watts is equal to
1 hp
Pi
100 hp
10 hp
25: What type of voltage cause a potential relay to open?