Topics: All categories in the pool
1: Dew point is
- the temperature of air of 50% RH
- the temperature below which water vapor in the air will start to evaporate
- the temperature above which water vapor in the air will start to condense
- the temperature below which water vapor in the air will start to condense
2: In a refrigeration system, you open a valve from the condenser and collect some material on a clean white sheet of bond paper, which of the following would you most likely be testing for?
- checking the level of refrigerant in the system
- testing for oil in the system
- testing for moisture in the system
- none of the above
3: 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
4: Usually dry bulb temperature is
- same as wet bulb temperature
- higher than wet bulb temperature
- not important and shall be ignored
- lower than dry bulb temperature
5: Three-phase motors have what type of windings?
- one start winding and one run winding.
- three run windings
- three run windings and 3 start windings
- three start windings
6: A plug containing an alloy that will melt at a specific temperature to relief pressure is a
- relief plug
- fusion plug
- rupture plug
- fusible plug
7: The principle used in continuous type absorption systems is
- Charles's Law
- Dalton's Law
- Ohm's Law
- Boyle's Law
8: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 44 lbs
- 22 lbs
- 6.6 lbs
- 13.9 lbs
9: When energized, a normally open relay will be
- open
- noisy
- closed
- depends on the type and class of the relay
10: What effect does the temperature of air have on humidity?
- warmer air holds more moisture then cooler air
- cooler air holds more moisture then warmer air
- air has no effect of humidity
- none of the above
11: R-22 falls under which safety classification?
- A-1
- B-2
- A-2
- B-1
12: What is the typical air conditioning operating pressures for 410A?
- 60 psi suction, 210 psi discharge
- 25 psi suction, 125 psi discharge
- 105 psi suction, 350 psi discharge
- None of the above
13: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 18
- 33
- 50
- 22
14: How are safety controls wired in a circuit?
- Series
- Series/parallel
- Parallel
- Either series or parallel
15: Give an example of a secondary coolant?
- R-718
- R-12
- R-410A
- R-717
16: Which of the following types of oils are hygroscopic?
- polyolester (POE)
- polyalkylene glycol (PAG)
- naphthene mineral
- both a and b
17: Liquid level gauges must be provided with what?
- A low level mark
- A red line
- A relief valve
- Automatic shut-offs
18: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
19: The generator shell contains the
- condenser and the absorber
- condenser and the generator
- condenser, the evaporator, and the generator
- evaporator and the absorber
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
- compressor
- outside the machinery room
- evaporator
21: Where are the three places that the discharge from an ammonia relief valve be piped?
- atmosphere, tank containing water, where the A.H.J. indicates
- underground, into drain, into mechanical room
- to chemical neutralizing tank only
- none of the above
22: The formula for Pure Power in a resistance circuit is
- Kw = volts X amps
- Watts = volts X amps
- Watts X amps.
- Watts X power factor
23: R-410A is classified as a ____ refrigerant on the safety matrix.
- A-1
- A-2
- B-2
- B-1
24: What is the minimum height refrigeration piping should be placed against walls?
- 7.25'
- 72"
- 6'
- Ceiling height
25: What does safe access mean?
- Locked doors
- A clear unobstructed path to the equipment and controls
- OSHA approved
- Well-lit exit signs