Topics: All categories in the pool
1: A hotel is considered a _______ occupancy.
- institutional
- residential
- mercantile
- commercial
2: After setting up a forward curved fan for the desired conditions, something happened to lower the total static pressure the fan had to operate against. Which would occur?
- RPM and CFM increase
- CFM and HP increase
- CFM and HP decrease
- CFM and RPM decrease
3: The gauge thickness required on a CO2 tank construction is
- 5/16"
- 3/32"
- 1/16"
- 1/8"
4: Bubbles in the liquid line sight glass could be caused by
- overcharge of oil
- bad low pressure switch
- plugged drier
- leaking discharge valves in the compressor
5: Fractionation occurs when
- the pressures decreases as the heat load decreases
- the pressures increase as the heat load increases
- when a fraction of refrigerant is added as the full charge
- some of the blended refrigerant evaporates or condenses before the rest of the blend
6: Each machinery room shall contain
- smoke and fire alarms as well as three means of egress and that egress must meet 528 CMR ventilation requirements
- high and low pressure controls
- a refrigerant detector located in an area where the refrigerant from a leak will concentrate
- a toxicity detector where the presence of ammonia or lithium bromide from a leak will concentrate
7: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
8: If the power element on an expansion valve should lose its charge, the valve would
- Stay open
- Close
- Under feed
- Over feed
9: A Lithium-bromide system is an absorption system that
- uses water as a absorbent and lithium bromide as a refrigerant
- uses water as a refrigerant and lithium bromide as an absorbent
- uses salts as an absorbent and lithium bromide as a refrigerant
- uses ammonia as a refrigerant and lithium bromide as an absorbent
10: Ohm's Law indicates Amps X Resistance = ___________.
- Ohms
- Impedance
- Volts
- Current
11: When an inspection is needed, how often must it be done?
- every 24 months
- every 18 months
- every 36 months
- annually
12: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
13: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or more
- vessels of 3 cubic feet or less
- vessels of 3 cubic feet or more
- vessels of 10 cubic feet or less
14: Which refrigerant class listed below is the most flammable?
- A-1
- C-3
- A-3
- B-2
15: How many gallons of water do you need per pound of ammonia?
- 1
- 50
- 10
- 100
16: What was the main reason for enacting the no venting rule of July 1, 1992?
- Ozone depletion
- Green house effect
- Global warming potential
- All of the above
17: Which is considered the more efficient condenser?
- air cooled
- fan cooled
- spray cooled
- water cooled
18: Pairs of mating stop valves that allow sections of a system to be joined before opening these valves or separated after closing them are
- companion or block valves
- king valves
- gate or globe valves
- ball valves
19: A Low-Probability System
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is such that a leak of refrigerant from a failed connection will enter the occupied space
- is a system highly likely to leak form a failed connection or component of such system
- is such that a leak of refrigerant from a failed connection can not enter the occupied space
20: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?
- 4%
- 2%
- 25%
- 1%
21: Heat cannot of itself, pass from a
- cold to a warmer body
- warm to a colder body
- state of hot energy to a state of cold energy
- None of the above
22: Fusible plugs must have what marked on them?
- Melting temperature in F
- Melting temperature in C
- Opening pressure
- All of the above
23: Walls and doors of a machinery room shall be at least _____ hour(s) fire rated.
- 5
- 2
- 1
- 3
24: The density of a gas refers to
- pounds per square foot
- pounds per cubic foot
- cubic feet per pound
- pounds per absolute pressure
25: Which of the following is an example of an azeotropic refrigerant?
- R-500
- R-410A
- R-404A
- R-134A