Refrigeration RT/RC Prep Quiz

Topics: All categories in the pool

Quiz Result Settings

1: If the suction pressure is low and the evaporator temperature high, the cause will be a?

  • starved evaporator
  • too small evaporator
  • compressor suction valve stuck open
  • overcharged

2: The reversing valve is commonly used

  • on commercial system that involve two different temperatures
  • when the code requires a check valve
  • on multiple compressor systems
  • on all heat pumps

3: In an A/C unit, dirty filters will cause

  • high discharge pressure
  • low suction pressure
  • low oil pressure
  • high suction pressur

4: Cooling tower lowers condenser water temp by

  • running water thru a secondary heat exchanger
  • evaporative cooling
  • condensation
  • running fans at 100%

5: Ammonia systems use ____ pressure to adjust oil pressure

  • liquid
  • air
  • stream
  • discharge

6: The rupture disc on a low-pressure chiller typically releases pressure at

  • 5 psig
  • 0 psig
  • 10 psig
  • 15 psig

7: What is R-22?

  • HFC
  • Chlorofluoromethane
  • CCFCM
  • Chlorodifluoromethane

8: R-718 is rated unlimited for refrigeration quantity contained in a system. Why?

  • Because it's a non-flammable refrigerant
  • Because it's cheap
  • Because it's water
  • R-718 is not rated unlimited because it's a dangerous refrigerant

9: B3 refrigerants are considered

  • non-toxic but non-flammable
  • non-toxic but flammable
  • toxic and highly flammable
  • toxic but non-flammable

10: On a day with low relative humidity, the two thermometers on a sling psychrometer will read

  • a ling psychrometer doesn't have two theremometers.
  • far apart or greater difference
  • nearly the same
  • 2F difference

11: What refrigerant doesn't have to be classifted?

  • R-134a
  • R-718
  • R-717
  • R-711

12: 1 HP = ____ Watts?

  • 11,239
  • 3.1416
  • 746
  • 3,412

13: The critical temperature of a refrigerant gas occurs when

  • any increase in pressure will not liquefy the gas
  • the gas returns to a liquid
  • the gas is no longer saturated
  • any decrease in pressure will cause condensation

14: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig

  • 255 psig
  • 125 psig
  • 327 psig
  • 365 psig

15: How many groups of refrigerants are there?

  • 5
  • 7
  • 1
  • 3

16: If your suction line is warmer than the room temperature, this may indicate

  • a low charge
  • plugged air filter
  • below normal superheat
  • an over charge

17: When testing systems using non-positive displacement compressors, the entire system shall be considered for test purposes as the low side.

  • True
  • False

18: What is absolute humidity?

  • the amount of moisture in the air per one pound of 50% RH air
  • the amount of moisture in the air in grains of cubic feet of volume
  • the amount of moisture in the air in grains of square feet of volume
  • none of the above

19: Direct systems using Group II refrigerants

  • shall not be used for air condition for human comfort
  • shall be installed per instruction of the AHJ
  • shall be installed in Class T machinery rooms
  • shall be allowed to be used for human comfort.

20: A chilled water pump suction gauge reads 10 psig. Discharge gauge reads 48 psig. The head in feet of the pump is working against

  • 88
  • 116
  • 108
  • 38

21: Evaporators located ____inches of a heating coil shall be equipped whit a pressure relief device.

  • 15
  • 24
  • 10
  • 18

22: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)

  • Pressure gauge
  • Temperature gauge
  • Sight glass gauge
  • All of the above

23: Watt's Law indicates Volts X Amps = _________.

  • Watts
  • Resistance
  • Current
  • Ohms

24: The 4 basic methods of determining whether the proper amount of refrigerant is being introduced into the system are

  • Buss-eye, weight, pressure, and frost line
  • sight glass, weight, pressure, and frost line
  • sight glass, weight, pressure, and dipstick
  • sight glass, weight, paper method, and frost line.

25: What is the maximum voltage range allowed on an electrical circuit?

  • 15%
  • 5%
  • 20%
  • 10%