Topics: All categories in the pool
1: The test pressure applied to the high side of each factory-assembled refrigerating system shall be at least equal to the design pressure of
- the high side
- the aggregate of the high side and low side
- 2.5 times the design pressure
- the low side
2: Which refrigerant is lighter than air?
- R-11
- R-134a
- R-717
- R-123
3: A Lithium-bromide system is an absorption system that
- uses salts as an absorbent and lithium bromide as a refrigerant
- uses ammonia as a refrigerant and lithium bromide as an absorbent
- uses water as a refrigerant and lithium bromide as an absorbent
- uses water as a absorbent and lithium bromide as a refrigerant
4: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
- pick-up voltage
- lift voltage
- run voltage
- boost voltage
5: R-12 is
- dichloromethane
- dichlorofluoromethane
- trichlorofluoromethane
- dichlorodifluoromethane
6: R-22 falls under which safety classification?
- A-1
- B-2
- A-2
- B-1
7: Low pressure systems have what kind of compressor?
- Rotary
- Reciprocating
- Centrifugal
- Scroll
8: 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
9: In a system designed for sub-zero ambient temperatures, what must be added?
- Low-ambient kit
- Nitrogen
- Booster compressor
- Infrared dye for leak identification
10: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
- lower
- there is no Group B1 refrigerants
- the same
- higher
11: 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
- 350
- 100
- 50
12: What type of relief valve is used on a CO2 system?
- glove disc
- gate valve
- fusible plug
- rupture disc
13: One atmosphere equals
- 29.4
- 0 psig
- 0 psia
- 14.7
14: 1 HP = ____ Watts?
- 11,239
- 3.1416
- 746
- 3,412
15: What is an egress?
- An escape route
- A code violation
- A valve put on the low side of the system to prevent frosting
- An entrance or exit
16: What must be done to refrigerant pipes before being buried?
- Certified
- Leaked checked
- Encased
- Coated
17: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
- Nesting scrolls
- Fan-like action
- Suction and discharge valves
- Rotating vanes
18: In an electrical circuit, what is potential measured in?
- Amps
- Ohms
- Volts
- Herys
19: A pressure relief should be located at least _______ from windows and doors.
- 30'
- 20'
- 25'
- 15'
20: "P" represents ______ in the Watt's law formula
- voltage
- reactance
- watts
- amperage
21: The location of the thermal bulb for the TXV on the evaporator effects
- both the pressure and temperature in the feeler bulb
- the amount of superheat required to operate the TXV
- the amount of liquid in the evaporator
- the amount of gas in the evaporator
22: Pressure vessel having an inside diameter exceeding 6” with an internal pressure greater than 15psig shall be marked directly on or on the nameplate the letters _______________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- “UM” and “UV”
- “UV”
- “U” or “UM”
- “UL”
23: Who authorizes changes to the safety codes?
- Person in charge of the facility
- Contractor who last serviced the system.
- Board of Boilers
- Person who pulled the permit
24: Who approves containers for refrigerants?
- D.O.T
- E.P.A
- D.O.E
- D.O.D
25: R-718 is rated unlimited for refrigeration quantity contained in a system. Why?
- Because it's cheap
- R-718 is not rated unlimited because it's a dangerous refrigerant
- Because it's a non-flammable refrigerant
- Because it's water