Topics: All categories in the pool
1: What refrigerant were phased out in 2004?
- R-22
- R-11
- R-134a
- R-12
2: A chiller entering and leaving temperature difference is?
- 50 degrees F
- 10 degrees F
- 20 degrees F
- 5 degrees F
3: If your suction line is warmer than the room temperature, this may indicate
- plugged air filter
- a low charge
- below normal superheat
- an over charge
4: What effect does the temperature of air have on humidity?
- warmer air holds more moisture then cooler air
- cooler air holds more moisture then warmer air
- air has no effect of humidity
- none of the above
5: A EPR valve is installed on what type of evaporators?
- high-temperature evaporators
- low-temperature evaporators
- shell and tube evaporators
- plate evaporators
6: Which refrigerant class listed below is the most flammable?
- B2
- A2
- C3
- A3
7: Setting a pressure relief device shall not exceed ___ of the design pressure
- 90%
- 100%
- 75%
- 80%
8: A chilled water pump suction gauge reads 10 psig. Discharge gauge reads 48 psig. The head in feet of the pump is working against
- 108
- 116
- 88
- 38
9: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
- 5 amps
- 10 amps
- 15 amps
- 20 amps
10: Mercury was used in thermometers primarily because it
- never freezes
- vaporizes at very high temperatures
- was inexpensive
- expands uniformly
11: R-410A is classified as a ____ refrigerant on the safety matrix.
- A-2
- A-1
- B-2
- B-1
12: Liquid level gauge glasses shall have automatic closing shut off valves, except Bull's eye or reflex type.
- True
- False
13: In a horizontal shell & tube condenser, the ammonia is liquefied by
- passing thru the tubes from top to bottom
- removing the latent heat of vaporization
- removing the latent heat of fusion
- water sprayed over condenser
14: 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
15: Group A1 refrigerants over ____ pounds in a system must discharge to the atmosphere
- 1,000
- 330
- 6.6
- 110
16: Which refrigerant(s) is an HFC?
- R-22
- R-410A
- R-502
- All of the above
17: The oil separator is always inserted in the system
- where it can be easily serviced
- in the discharge line
- in a cool spot
- to prevent oil logging
18: How many different groups of refrigerants are there?
- 7
- 3
- 15
- 11
19: What must be done to refrigerant pipes before being buried ?(8.10.4)
- Classifed
- Leak checked
- Certified
- Insulated and installed in a pipe duct (Encased)
20: Bubbles in the liquid line sight glass could be caused by
- bad low pressure switch
- leaking discharge valves in the compressor
- plugged drier
- overcharge of oil
21: Single compound Refrigerants are classified by what two criteria?
- Temperature range and hazardousness
- Flammability and temperature range
- Weight and color
- Flammability and toxicity
22: What is not a requirement of a Class T machine room?
- Fire hose connected to the building fire protection system.
- Self-closing doors
- Tight fitting doors
- Automatic ventilation
23: 14.7 psia is equivalent to
- atmospheric pressure at seal level
- 29.92" Hg
- 0 psig
- All of the above.
24: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use fusible plugs
- shall use pressure relief devices
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
25: 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.