Topics: All categories in the pool
1: When using nitrogen for brazing, the pressure should be:
- Slightly below atmospheric
- 50-100 psig
- Very low
- 125 psig
2: What device measures the specific gravity of a substance?
- Hygrometer
- Thermometer
- Hydrometer
- Manometer
3: When is the only time you can leave a service container attached to a system?
- Leaking system
- Recovery
- Charging
- Both b and c
4: What is the purpose of suction/discharge traps?
- to ensure proper oil return to the compressor
- to keep oil inside the evaporator for proper oil return to the compressor
- to keep oil inside of the accumulator for proper return to the compressor
- all of the above
5: A multi-evaporator refrigeration system uses what type of valve to maintain evaporating temperatures?
- EPR valve
- Solenoid valve
- CPR valve
- EEV
6: What was the main reason for enacting the no venting rule of July 1, 1992?
- Ozone depletion
- Green house effect
- Global warming potential
- All of the above
7: If your suction line is warmer than the room temperature, this may indicate
- an over charge
- a low charge
- plugged air filter
- below normal superheat
8: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
- shall use pressure relief devices
- shall use fusible plugs
9: A 24 volt transformer with a 240 volt primary can handle how many amps?
- 10 amps
- 20 amps
- There isn't enough information to answer.
- 24 amps
10: The certificate of inspection
- shall be posted and protected from dirt, water, and other elements
- shall be authorized by a notarized insurance company
- shall be $20 and an additional fee of $1 for each tone above 20 tons
- shall be posted on the compressor shell or electrical panel at the unit
11: On a TXV, the purpose of an external equalizer is to?
- Increase the pressure on the top of the power head diaphragm
- balance the evaporator load
- compensate for a pressure drop across the evaporator coil
- allow a greater adjustment spam
12: What type of relief valve is used on low pressure centrifugal compressor systems?
- Spring-loaded relief valve
- Rupture disc
- Purge relief
- None of the above
13: What are the three components of a transformer?
- Primary core, secondary coil, and high and low voltage connectors.
- Primary coil, secondary coil, and copper contacts
- Primary coil, secondary coil, and core
- Contacts, secondary coil, and core
14: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Heat
- Air
- Oil
- Electricity
15: 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)?
- centrifugal switch
- duel-voltage switch
- printed circuit board (PCB)
- motor starter
16: A run capacitor is wired in series with the _____ windings.
- start
- run
- start capacitor
- common
17: 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
- compressor
- outside the machinery room
- evaporator
- boiler
18: How are refrigerant blends classified?
- Based on the oil used
- Based on worst case fractionation
- Blends don't have to be classified
- Based on best case Fractionation
19: The formula for Pure Power in a resistance circuit is
- Watts = volts X amps
- Watts X power factor
- Watts X amps.
- Kw = volts X amps
20: Color is important in oil because
- it indicates the viscoisty.
- it makes sight glasses easy to read
- can tell us something about the refining of oil
- allows you to see into crankcase
21: When a refrigerating machinery room is used, the emergency procedures shall be posted
- on a conspicuous card located near the compressor
- outside the room, immediately adjacent to each door
- on a conspicuous card located near the evaporator
- inside the room, immediately adjacent to each door
22: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
23: Booster compressors, pump refrigerant into the
- heat & plate heat exchanges
- high side of the secondary compressor
- low side of the primary compressor
- receiver
24: Clearance volume
- varies depending on compressor speed
- affects compressor capacity
- has no effect on compressor capacity
- is the same on all compressors
25: When a refrigeration or air conditioning system is installed
- the form of certificate shall be authorized by the Department of Pubic safety
- a field inspection shall be made before it is put into service
- it shall not be operated below prescribed pressures
- it shall be approved by the owner for proper operation.