Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: 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.
15
25
10
20
2: What is the minimum height refrigeration piping should be placed against walls?
Ceiling height
6'
7.25'
72"
3: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are
sight glass, weight, pressure, and frost line
Buss-eye, weight, pressure, and frost line
sight glass, weight, pressure, and dipstick
sight glass, weight, paper method, and frost line.
4: Lithium-bromide, Li-Br, is best characterized as a
sugar
soil
sand
salt
5: What type of voltage causes the winding in a potential relay to open?
BEMF (Back Electro-Motive Force)
24V control voltage from the thermostat
120V line voltage
None of the above
6: In an A/C unit, dirty filters will cause
high discharge pressure
high suction pressur
low suction pressure
low oil pressure
7: R-11 has the greatest corrosive effect on
Bronze
Copper
Aluminum
Magnesium
8: Who approves containers for refrigerants?
D.O.T
E.P.A
D.O.E
D.O.D
9: The main cause of enacting the "no vending rule" of July 1st 1992 was
global warming potential
ozone depletion
both a & b
None of the above
10: How many gallons of water do you need per pound of ammonia?
1
50
10
100
11: R-12. R-22, and R-40 are considered Group I refrigerants.
True
False
12: One atmosphere equals
29.4
0 psig
0 psia
14.7
13: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
550
350
100
50
14: A class B1 refrigerant is considered
non-toxic but highly flammable
non-toxic and non-flammable
toxic but non-flammable
toxic and somewhat flammable
15: Bubbles in the liquid line sight glass could be caused by
bad low pressure switch
overcharge of oil
plugged drier
leaking discharge valves in the compressor
16: A restaurant is classified as a
large mercantile occupancy
mixed occupancy
commercial occupancy
public assembly occupancy
17: R-22 is considered a(n)
HCFC
CFC
HFC
HCFCH
18: The difference between saturated liquid and saturated vapor is
pressure
heat
temperature
volume
19: The first step in mechanical refrigeration is
condensation
expansion
compression
evaporation
20: Capacity control on an absorption system is typically accomplished by varying the
speed of the condenser water circulator pump
rate at which heat is supplied to the generator
pressure setting on the system's rupture disc
speed of the chilled water circulatory pump
21: In a low temperature refrigeration system, the benefit of the system using P.A.G. oil is
it is hydroscopic
it traps moisture
viscosity
all of the above
22: Total heat of a substance is considered
sensible heat
enthalpy
specific heat
empathetical
23: Which is the lowest vacuum?
5 psig
5" hg
10 psia
1,000 Microns
24: What should never be used in pressure testing refrigeration systems?