Topics: All categories in the pool
1: Which of the following is NOT a positive displacement compressor?
- centrifugal
- screw
- scroll
- reciprocating
2: Where can 50/50 solder be used on?
- suction line
- liquid line
- discharge line
- none of the above
3: The critical temperature of a refrigerant gas occurs when
- the gas is no longer saturated
- any decrease in pressure will cause condensation
- the gas returns to a liquid
- any increase in pressure will not liquefy the gas
4: Class T machine room
- has no flame producing apparatus permanently installed
- shall have refrigerant leak detecting systems installed inside and outside the room
- shall have remote controls to stop the action of the refrigerant compressor
- shall include closets used for setting equipment
5: When can recovered refrigerants be reused?
- They can't
- Only when used in original owner's equipment
- Only if used in 30 days of recovery
- None of the above
6: When using nitrogen for brazing, the pressure should be:
- 50-100 psig
- 125 psig
- Very low
- Slightly below atmospheric
7: It is permissible to use a single-pole switch on a 2 HP motor running at 240 volts as long as the switch is rated for at least 2x FLA.
- True
- False
8: 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
9: A chiller entering and leaving temperature difference is?
- 10 degrees F
- 5 degrees F
- 50 degrees F
- 20 degrees F
10: 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.
- 550
- 50
- 350
- 100
11: On cooling towers, what causes the condenser water to drop
- tower fans
- evaporation of the water droplets
- sensible heat
- ambient temperatures
12: A Category D fluid
- is when the fluid handled is non flammable, nontoxic, and not damaging to human as defined in ANSI/ASME Process Piping.
- is when the design pressure does not exceed 150 psi
- a fluid for service piping in which the potential for personnel exposure is judged to cause harm and irreversible damage to those persons exposed to it
- Both a and b are correct
13: A class A3 refrigerant is considered
- non-toxic and non-flammable
- toxic and non-flammable
- non-toxic but highly flammable
- toxic and somewhat flammable
14: _____ and its alloys are suitable for use with ammonia systems.
- Copper
- Aluminum
- Zinc
- Magnesium
15: What is a Category "D" fluid?
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and design temperature is between -20F to 366F
- A typical refrigerant used on newer air conditioning and heat pump ssytems
- Any fluid that exceeds 150 psig and has design temperature of over 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily contact
16: Which winding have the most turns?
- depends on the motor phase
- Start
- they have equal amount of turns
- run
17: When must refrigeration system covered by the code be inspected?
- Not required
- Annually
- Annually and when installed
- Upon installation
18: Which of the following is not an air velocity meter?
- Hydrometer
- Anemotherm
- Anemometer
- Velometer
19: Brazed joints melt at temperatures above
- 1,000F
- 1,200F
- 500F
- 800F
20: What happens after your initial inspection of a pressure vessel?
- There is a temporary shut-down until a final inspection can be performed.
- Inspector leaves a metal tag with a certification listed on it
- Notify the Fire Marshal that the system has been inspected and approved
- Notify the AHJ to let them know that the system been inspected
21: Who approves containers for refrigerants?
- D.O.T
- D.O.E
- E.P.A
- D.O.D
22: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
23: In an electrical circuit, what is potential measured in?
- Volts
- Amps
- Herys
- Ohms
24: How are a compressor and condenser fan wired?
- parallel-series
- series-parallel
- parallel
- series
25: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- 1 Therm
- 1 Kelvin
- 1 BTU
- The rate of conduction