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
20
25
10
2: What is an example of institutional occupancy?
Shopping mall
Football stadium
Dorms
Hospital
3: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
800F
1000F
700F
600F
4: Which refrigerant class listed below is the most flammable?
C-3
A-1
A-3
B-2
5: Mercury was used in thermometers primarily because it
vaporizes at very high temperatures
never freezes
was inexpensive
expands uniformly
6: What kind of system uses two different refrigerants in separate systems dependent on each other?
Cascade
Low pressure
Simple
R-414B
7: Pressure vessels nameplate markings must be compliant with the
ASHRAE 34 Standards
CMR-588 & CMR-528
ASME Boiler and Pressure Vessel Code
All of the Above
8: While the system is operating, the discharge line should be
room temperature
too hot to hold by hand
at the same temperature as the crankcase
10-15F warmer than ambient
9: A single pole-double throw switch used how many wires excluding the ground wire?
two
three
five
four
10: What device should be used on low-temperature freezers?
oil separator
discharge muffler
hot-gas by-pass
high capacity TXV
11: "I" represents _______ in the Watt's law formula.
amperage
voltage
watts
reactance
12: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?
fusible plug
relief valve
rupture disc
all of the above
13: Sublimation occurs when
ice melts and turns to water
gas is formed from a liquid
gas is formed directly from a solid
liquid is formed from a gas
14: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
strong solution
concentrated solution
absorbed solution
weak solution
15: A relief valve discharge capacity is rated in
temperature minus pounds of air per second divided by release rate squared
Pounds of air per minute.
PSIA
PSIG
16: Can ammonia be used on domestic system?
no, unless there is proper ventilation system installed
yes
no
yes, for systems under 10 tons
17: B3 refrigerants are considered
non-toxic but non-flammable
non-toxic but flammable
toxic and highly flammable
toxic but non-flammable
18: What is not a requirement of a class T machine room?
fire hose connection to the building fire protection system
self-closing doors
automatic ventilation
tight fitting doors
19: Who approves containers for refrigerants?
E.P.A
D.O.E
D.O.T
D.O.D
20: Bubbles in the liquid line sight glass could be caused by
leaking discharge valves in the compressor
bad low pressure switch
overcharge of oil
plugged drier
21: The best way to detect ammonia in brine is
carbonation of soda
nessler regaent
CO2 gas
potassium of line
22: On a pumpdown system, the liquid-line solenoid is controlled by the
low-ambient controller
thermostat
defrost timer
low pressure switch
23: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.