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
Moisture indicator
Muffler
Stop valve
2: Pipe identification labels are required when the system contains more than
110 lbs
120 lbs
55 lbs
65 lbs
3: What type of material can't be used on the outlet of a relief valve?
Magnesium alloy
PVC
Copper
Stainless steel
4: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)
70F
32F
77F
58F
5: What happens to copper joints when overheated?
nothing
joint becomes oxidized and ditorted
copper becomes harder
none of the above
6: Which creates more of a heat load?
30% RH
90% RH
50% RH
70% RH
7: At higher altitudes, the boiling point of refrigerant is
higher
the same
equal to the coefficient of water at 32F
lower
8: Which of the following is a drop-in for R-22
R-410A
R-134A
R407C
None of the above
9: The generator shell contains the
condenser, the evaporator, and the generator
condenser and the absorber
condenser and the generator
evaporator and the absorber
10: Name an HCFC refrigerant(s):
R-22
R-123
R-11
both a & b
11: On a single phase motor, when does the start winding cut out?
100% of its RLA speed
75% of its RLA speed
25% of its RLA speed
50% of its RLA speed
12: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
the outdoors
Machinery rooms need not be vented
the return air ducted system
the mechanical room housing the refrigeration system
13: What is potential measured in?
Ohms
Volts
Henrys
Amps
14: The instrument used to measure the specific gravity of absorption chiller solutions is the
anemometer
hydrometer
Psychrometer
refractometer
15: How many flammability classifications are refrigerants in?
3
7
2
5
16: What is used to check very low pressure?
Manometer
Hydrometer
Hygrometer
Velometer
17: Large vessels containing refrigerant ______________________ from using two or more pressure-relief devices in parallel to obtain the required capacity.
of Group B2 refrigerant shall be prohibited
containing R-11, R-123 & R-717 exclusively shall not be prohibited
shall be prohibited
shall not be prohibited
18: The main purpose of the accumulator is to
store liquid refrigerant
provide space for vapor to accumulate
provide space for the accumulation of oil and containminants
prevent liquid slugs at the compressor
19: Machinery rooms must be vented to ______?
unoccupied spaces
outdoors
basement
neutralizing tank
20: Start to Run windings will have what resistance?
Somewhere between the actual start winding and run winding resistance value
All will be at equal values
The most resistance value
The least resistance value
21: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
2F difference
a ling psychrometer doesn't have two theremometers.
far apart or greater difference
nearly the same
22: If the power element of an expansion valve should lose its charge the valve would
underfeed the evaporator
go closed
overfeed the evaporator
go open
23: Low pressure systems have what kind of compressor?
Rotary
Reciprocating
Centrifugal
Scroll
24: What pipe can not be used for refrigeration?
L
N
K
M
25: Bubbles in the liquid line sight glass could be caused by