Topics: All categories in the pool
1: When the compressor is below the condensor
- traps are needed on the oil return line
- traps are needed on the suction line
- traps are needed on the discharge line
- traps are not needed on this type of system
2: A class B1 refrigerant is considered
- toxic but non-flammable
- non-toxic but highly flammable
- toxic and somewhat flammable
- non-toxic and non-flammable
3: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 22 lbs
- 13.9 lbs
- 6.6 lbs
- 44 lbs
4: Machinery rooms must be vented to ______?
- neutralizing tank
- basement
- unoccupied spaces
- outdoors
5: Color is important in oil because
- allows you to see into crankcase
- can tell us something about the refining of oil
- it makes sight glasses easy to read
- it indicates the viscoisty.
6: Low pressure chiller systems use what type of compressor?
- Reciprocating
- Screw
- Scroll
- Centrifugal
7: Ohm's Law indicates Amps X Resistance = ___________.
- Current
- Impedance
- Volts
- Ohms
8: What type of material can't be used on the outlet of a relief valve?
- Stainless steel
- Copper
- Magnesium alloy
- PVC
9: What pipe can not be used for refrigeration?
- K
- N
- L
- M
10: The rupture disc on a low-pressure chiller typically releases pressure at
- 5 psig
- 15 psig
- 0 psig
- 10 psig
11: On cooling towers, what causes the condenser water to drop
- sensible heat
- evaporation of the water droplets
- tower fans
- ambient temperatures
12: What is a megaohm meter?
- An electric meter that measures very high resistance values by sending a high DC voltage signal into the object being tested
- Is an electric meter that measures extremely low resistance valves by sending high DC voltage signal into the object being tested.
- An electric meter that measures very high resistance values by sending a low voltage AC signal into the object being tested
- An electric meter used by electricians to test large 3-phase blower motors for the correct rotation
13: The critical temperature of a refrigerant gas occurs when
- any decrease in pressure will cause condensation
- any increase in pressure will not liquefy the gas
- the gas is no longer saturated
- the gas returns to a liquid
14: 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
15: What is the voltage of each leg to ground of a three-phase motor with a 460v supply voltage?
- 120v
- 240v
- 277v
- 208v
16: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
17: Which of the following is an example of an azeotropic refrigerant?
- R-134A
- R-404A
- R-410A
- R-500
18: Which is the lowest vacuum?
- 5 psig
- 10 psia
- 1,000 Microns
- 5" hg
19: Systems containing more than 110 pounds must have stop valves located at the
- compressor suction inlet
- compressor discharge outlet
- receiver inlet and outlet
- All of the above
20: The oil separator is always inserted in the system
- where it can be easily serviced
- in a cool spot
- to prevent oil logging
- in the discharge line
21: Can a R22 line set be reused for a 410A system and if it can be reused, what must be done to it?
- Flush with ammonia
- Flush with R-718
- Flush with RX-11
- Flush with R-11
22: Clearance volume
- has no effect on compressor capacity
- affects compressor capacity
- is the same on all compressors
- varies depending on compressor speed
23: Who approves containers for refrigerants?
- D.O.E
- D.O.D
- E.P.A
- D.O.T
24: The measurement of heat in a particular substance is
- latent heat
- specific heat
- enthalpy
- sensible heat
25: Megaohm meters can detect a ground in the
- up to 1,000,000 ohms
- 10,000,000 ohms or higher
- up to 10,000 ohms
- up to 1,000 ohms