Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: With a 5/8" X 5/8" x 3/4" tee, what size is the center connection?
3/8"
1/2"
5/8"
3/4"
2: What section governs pressure vessels?
Section 1 ASHREA 15 ASME fired
Section ASHREA 34
OSHA
Section 8 ASHREA 15 ASME unfired
3: On a centrifugal compressor, stationary diffuser vanes are needed to
convert velocity energy to pressure
increase the clearance space
prevent high pressure on the packing
stop gas flow
4: Halogenated refrigerants cannot be used with what material?
Stainless steel
Magnesium alloy
Copper
Aluminum
5: What type of material can't be used on the outlet of a relief valve?
PVC
Copper
Stainless steel
Magnesium alloy
6: Capacitors are rated in
megaohms
micro-farads
volt - amperes
kelvins
7: High pressure controls should be set no higher than
10% of set point
80% of set point
25% of set point
90% of set point
8: If the spring is adjusted to increase the superheat, this new setting will
have no effect on the frost line
shorten the frost line
lengthen the frost line
allow more liquid into the evaporator
9: What would be the classification of a church?
Industrial
Large mercantile
Institutional
Place of assembly
10: copper and its alloys shall not be used in contact with _____ except as a component of bronze alloys for bearing or other non-refrigerant containing uses.
HCFC-123
Lithium bromide
CFC-11
ammonia
11: 1 HP = ____ Watts?
746
11,239
3.1416
3,412
12: What is the amp draw of a 40 VA transformer at 24 volts
1.6 amps
1K amps
1,000 amps
106 amps
13: The measurement of heat in a particular substance is
enthalpy
sensible heat
specific heat
latent heat
14: Which refrigerant replaced R-12?
R-22
R-134A
R-410A
R-407A
15: One atmosphere equals
0 psig
29.4
0 psia
14.7
16: If the power element on an expansion valve should lose its charge, the valve would
Close
Under feed
Over feed
Stay open
17: 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.
50
24
75
100
18: Pipe identification labels are required when the system contains more than
110 lbs
120 lbs
55 lbs
65 lbs
19: Increasing superheat will do what to your system?
Increase liquid flow
Nothing
Decrease liquid flow
Increase gas flow
20: What type of oil is used in R-410A systems?
mineral oil
polyalkylene glycol (PAG)
naphthene
polyolester (POE)
21: Booster compressors connect to the ____ side of the compressor
liquid
oil side
vapor
low side
22: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
70.8 psig
43.3 psig
50.2 psig
66.1 psig
23: On a pumpdown system, the liquid-line solenoid is controlled by the
low-ambient controller
low pressure switch
thermostat
defrost timer
24: In a motor, an internal overload might open if
there's an excess current draw through the motor
there's an open start winding
there's a direct short
there was a high pressure refrigerant was used for a low pressure system.
25: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit