Topics: All categories in the pool
1: A R-410A system running with a condensing temperature of 110F and 50F evaporator temperature will read pressures of ___ on the high side and ___ on the low side
- 257 psig, 77 psig
- 226 psig, 68 psig
- 365 psig, 120 psig
- 455 psig, 185 psig.
2: 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.
- 100
- 350
- 550
- 50
3: What device removes the start winding from the circuit of a split-phase motor once the motor reaches 75% of its rated load amps (RLA)?
- printed circuit board (PCB)
- motor starter
- centrifugal switch
- duel-voltage switch
4: Suction valve unloaders afford an effective means of
- superheat control
- evaporator control
- capacity control
- refrigerant control
5: Low pressure systems have what kind of compressor?
- Rotary
- Reciprocating
- Centrifugal
- Scroll
6: A relief valve shall be located at least ___ above grade.
- 25'
- 36'
- 10'
- 15'
7: Refrigeration piping before being buried shall be
- leak tested
- encased in pipe duct
- pressure tested
- All of the above
8: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.
- 99%
- 80%
- 75%
- 90%
9: Insurance companies shall forward each inspection report of all refrigeration or A/C systems to the Chief of Inspections within
- 30 days
- 2 months
- 14 days
- 1 week
10: What measures gas pressure?
- Manometer
- Hydrometer
- Hygrometer
- Barometer
11: What is the refrigerant dichlorodifluoromethane?
- R-12
- R-22
- R-134A
- R-123
12: Fusible plugs shall not be used with pressure vessels of
- 15 square feet or less
- 3 cubic feet or more
- 3 cubic feet or less
- 15 cubic feet or more
13: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)
- Pressure gauge
- Temperature gauge
- Sight glass gauge
- All of the above
14: R-123 belongs to Group
- B-3
- A-3
- B-2
- B-1
15: Ammonia shall be discharged into ____________ or a tank containing one gallon of water for every pound of ammonia.
- the atmosphere
- a de-pressurized recovery tank with a silver top and yellow bottom
- a tank containing two pounds of a water/lithium bromide mix for every pound of ammonia
- All of the above
16: An oil pressure safety switch should be set at
- 5 to 10 psi above low side pressure
- 5 to 10 psi below low side pressure
- 10 to 15 psi below low side pressure
- 10-15 psi above low side pressure
17: Which occupancy can ammonia be used in?
- industrial
- depends on the quantity of freon
- commercial
- redifential
18: Pressure vessels having an inside diameter of 6” or less shall be protected by
- Pressure vessels having an inside diameter of 6” or less need no such protection unless otherwise specified
- either a fusible plug or a pressure relief device
- a fusible plug
- a pressure relief device
19: A pressure relief should be located at least _______ from windows and doors.
- 25'
- 30'
- 15'
- 20'
20: Emergency shutdown procedures, including precautions to be observed in case of a breakdown or leak over 55 lbs of refrigerant charge, shall be displayed on a conspicuous card located as near as possible to the
- boiler
- outside the machinery room
- evaporator
- compressor
21: How many groups of refrigerants are there?
- 1
- 5
- 7
- 3
22: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
23: How many volts would you read on a 480V system phase to phase?
- 480
- 277
- 1/3 the voltage
24: Class A refrigerants are considered
- non-flammable
- flammable
- toxic
- non-toxic
25: Stop valves shall not be permitted between the system and the
- relief valve
- bleed valve
- service valve
- condenser