Topics: All categories in the pool
1: An example of an "Expendable Refrigerant" is
- lithium bromide
- liquid nitrogen
- liquid oxygen
- ammonia
2: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?
- 1%
- 4%
- 2%
- 25%
3: How much refrigerant can be stored in a mechanical room outside of the system?
- 100
- 330
- 200
- 150
4: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?
- R-113
- R-11
- R-12
- R-22
5: A normal operating evaporator temperature of R-22 for air conditioning is typically
- 32F
- 45F
- 58F
- 55F
6: Pressure vessels with an internal volume of 3 cubic feet or less
- shall use pressure relief devices
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
7: The main cause of enacting the "no vending rule" of July 1st 1992 was
- global warming potential
- ozone depletion
- both a & b
- None of the above
8: How many BTU's is produced by one watt of energy
- 3.41
- 2.57
- 1
- 3.00
9: R-11 belongs to Group
- B-1
- B-3
- A-1
- A-2
10: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the
- low side of the system
- high side float assembly
- cap tube
- none of the above
11: A capacitor in series with the start windings will do what?
- Nothing
- Decrease the RLA to within 10% of its rating
- Increase starting torque
- Increase run efficiency by 10% of its rating
12: An evaporator coil located near heating coil shall have a pressure-relief device installed within ______ inches of the evaporator.
- 48
- 36
- 24
- 18
13: A professional or office building would be considered what type of occupancy?
- mercantile
- business
- commercial
- public assembly
14: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 6.6 lbs
- 13.9 lbs
- 22 lbs
- 44 lbs
15: How many forces operate a thermostatic expansion valve?
- 4
- 3
- 1
- 2
16: According to the 522 CMR Board of Boilers, refrigerant detectors, alarms, and the refrigeration mechanical room ventilating systems shall be tested
- regularly
- bi-annually
- quarterly
- annually
17: Single compound Refrigerants are classified by what two criteria?
- Flammability and toxicity
- Weight and color
- Temperature range and hazardousness
- Flammability and temperature range
18: What refrigerant were phased out in 2004?
- R-12
- R-11
- R-134a
- R-22
19: A direct system
- is one which encloses a separate body of evaporative refrigerant
- is a self-contained complete factory made and tested system
- is where the refrigerant comes in contact with the space refrigerated
- is on where brine is cooled & circulated to the space refrigerated
20: A plug containing an alloy that will melt at a specific temperature to relief pressure is a
- relief plug
- rupture plug
- fusion plug
- fusible plug
21: In designing duct work, pressure and ______ need to be considered
- length
- CFM
- duct sealant used
- all of the above
22: What is potential measured in?
- Henrys
- Volts
- Amps
- Ohms
23: Which refrigerant class listed below is the most flammable?
- A-1
- A-3
- C-3
- B-2
24: Which occupancy can ammonia be used in?
- industrial
- depends on the quantity of freon
- commercial
- redifential
25: What is NOT a positive displacement compressor.
- Centrifugal
- Reciprocating
- Scroll
- Rotary