Massachusetts Refrigeration Tech/Contractors practice quiz
Refrigeration RT/RC Prep Quiz
Topics: All categories in the pool
1: Capacity control on an absorption system is typically accomplished by varying the
speed of the condenser water circulator pump
speed of the chilled water circulatory pump
rate at which heat is supplied to the generator
pressure setting on the system's rupture disc
2: It takes how many BTU/hr to melt one pound of ice at 32F
970
180
144
212
3: A professional or office building would be considered what type of occupancy?
business
public assembly
commercial
mercantile
4: Before determining if a machinery room equipment is excluded from following Ashrae 15, you must determine how many pounds of refrigerant per _____ cubic feet?
1,000
100
10,000
100,000
5: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?
1%
4%
2%
25%
6: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
Moisture indicator
Foot valve
Stop valve
Muffler
7: Where can 50/50 solder be used on?
suction line
liquid line
discharge line
none of the above
8: Refrigerant restricted in 2004 but used for transition for decades:
R-22
R-123
R-134A
R-11
9: On a day with low relative humidity, the two thermometers on a sling psychrometer will read
2F difference
nearly the same
a ling psychrometer doesn't have two theremometers.
far apart or greater difference
10: Two capacitors are wired in parallel. One capacitor has a value of 15uf. The other has a value of 25uf. What is the total value supplied?
40 uf
25 uf
15 uf
20 uf
11: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
15 amps
20 amps
5 amps
10 amps
12: Where would the EPR valve be located on a multiple evaporator system?
outlet of low temperature evaporator
inlet of the low temperature evaporator.
outlet of the liquid line
outlet of high temperature evaporator
13: Refrigeration piping before being buried shall be
leak tested
encased in pipe duct
pressure tested
All of the above
14: On a single phase motor, when does the start winding cut out?
Start windings do no cut-out of the run cycle
At 75% of its full rated speed
At 50% of its full rated speed
At 25% of its full rated speed
15: A 3-cubic foot receiver must have what type of relief valve?
fusible plug
relief valve
rupture device
none of the above
16: A direct system
is on where brine is cooled & circulated to the space refrigerated
is one which encloses a separate body of evaporative refrigerant
is a self-contained complete factory made and tested system
is where the refrigerant comes in contact with the space refrigerated
17: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
pick up voltage
boost voltage
lift voltage
run voltage
18: The boiling point of a refrigerant is based on
Temperature
Heat content
a pressure-temperature relationship
None of the above.
19: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
strong solution
weak solution
absorbed solution
concentrated solution
20: A start capacitor is wired in _____ with the start windings.
series-parallel
junction
parallel
series
21: 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
50.2 psig
66.1 psig
43.3 psig
22: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
over pressure protection and a rupture disc
over pressure protection
Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
over pressure protection as well as a temperature protection device
23: Gauge pressure is
Barometric pressure
Force of pressure above that of atmosphere
Atmospheric pressure
Absolute pressrue
24: Low temperature systems should have what?
High pour point
Low pour point
High viscosity
None of the above
25: Heat that changes the physical state of a substance without effecting a change in its temperature is known as