Topics: All categories in the pool
1: _____ and its alloys are suitable for use with ammonia systems.
- Copper
- Aluminum
- Zinc
- Magnesium
2: The location of a thermal bulb of a TXV affects
- the amount of liquid in the condenser.
- the amount of liquid refrigerant in the evaporator
- subcooling
- the amount of liquid returning to the compressor
3: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
- 1.5
- 1
- 1.2
- 2.2
4: The heat picked up in the evaporator must equal to
- the heat of compression
- the heat gained by the condenser
- the heat lost by the medium being cooled
- the heat giving by the condenser
5: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
- Enthalpy
- Specific heat
- Sensible heat
- Latent heat
6: What is not a requirement of a class T machine room?
- automatic ventilation
- self-closing doors
- fire hose connection to the building fire protection system
- tight fitting doors
7: Group A2 refrigerants have a ______ toxicity rating than Group B1 refrigerants.
- higher
- there is no Group B1 refrigerants
- the same
- lower
8: Machinery rooms must be vented to ______?
- outdoors
- neutralizing tank
- basement
- unoccupied spaces
9: In an A/C unit, dirty filters will cause
- high discharge pressure
- high suction pressur
- low suction pressure
- low oil pressure
10: Ammonia systems use ____ pressure to adjust oil pressure
- discharge
- liquid
- stream
- air
11: Which of the following are considered inorganic refrigerants?
- R-717 and R-718
- 410A and R-407C
- R-500 and R-502
- None of the above
12: Crankcase heaters are energized
- when the compressor is off
- to prevent compressor freeze-up
- while the compressor is running
- to allow easy compressor start-up
13: What would be the classification of a church?
- Industrial
- Large mercantile
- Place of assembly
- Institutional
14: What type of copper is not permitted on refrigeration systems?
- Type M
- Type L
- Type K
- Type N
15: Class T machine room
- shall include closets used for setting equipment
- shall have remote controls to stop the action of the refrigerant compressor
- has no flame producing apparatus permanently installed
- shall have refrigerant leak detecting systems installed inside and outside the room
16: Two systems using separate refrigerants that are superimposed upon one another is called
- booster
- cascade
- indirect
- single stage
17: A 120 volt motor rated at 1,800 watts. You find the motor is drawings 25 amps. The motor is
- drawing RLA and is running as it should
- drawing LRA and is seized and should be replaced.
- running hot
- none of the above
18: 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
19: Pressure vessels with an internal volume of 3 cubic feet or less
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
- shall use pressure relief devices
- shall use fusible plugs
20: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
- lower
- there is no Group B1 refrigerants
- the same
- higher
21: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Air
- Oil
- Heat
- Electricity
22: A solder joint melts at temperatures of
- 600F to 900F
- 400F to 800F
- 1,200F to 1,500F
- less than 400F
23: Gauge pressure is
- force of pressure above that of atmospheric
- atmospheric pressure
- absolute pressure
- what a gauge reads when checking pressures on a chilled water system.
24: Brazed joints melt at temperatures above
- 1,000F
- 1,200F
- 500F
- 800F
25: A relief valve shall be located at least ___ above grade.
- 10'
- 15'
- 25'
- 36'