Topics: All categories in the pool
1: Which has more turns in the windings: Start windings or Run windings?
- Start windings
- Run windings
- They both have the exact same turns
- Depends on the system and capacitor used
2: The first step in mechanical refrigeration is
- condensation
- expansion
- compression
- evaporation
3: A relief valve shall be located at least ___ above grade.
- 10'
- 25'
- 36'
- 15'
4: What is the refrigerant chlorodifluoromethane?
- R-12
- R-123
- R-134a
- R-22
5: Horizontal piping should be run level.
- No, unless the supervisor on the job says so.
- False
- True
- Yes, if the condenser is located above the evaporator
6: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.
- critical pressure
- high pressure
- design pressure
- low pressure
7: Pressure vessels nameplate markings must be compliant with the
- ASHRAE 34 Standards
- CMR-588 & CMR-528
- ASME Boiler and Pressure Vessel Code
- All of the Above
8: Large mercantile occupancy is
- a premise of that portion of a premise where more than 100 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise of that portion of a premise where more than 50 persons congregate on levels above of below street level to purchase personal merchandise.
- a premise or that portion of a premise where more than 200 persons congregate on levels above or below street level to purchase personal merchandise
- a premise or that portion of a premise where more than 1500 persons congregate on levels above or below street level to purchase personal merchandise
9: Evaporators within 18" of a heating coil must be equipped with a
- high limit control
- zone valve
- low limit control
- pressure relief device
10: Pressure vessels with an internal volume of 10 cubic feet or more
- shall use pressure relief devices or fusible plugs
- shall use fusible plugs
- shall use rupture discs or duel pressure relief valves
- shall use pressure relief devices
11: Secondary refrigerants are usually
- alcohol
- Prestone anti-freeze
- water or brine
- expensive
12: A water regulating valve opens when
- when the power is on there is an overcharge of refrigerant
- the head pressure rises
- the compressor is on
- when the power is on
13: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit
- 9.776 watts
- 9,776 watts
- 977.6 watts
- .9776 watts
14: The generator shell contains the
- condenser, the evaporator, and the generator
- condenser and the generator
- condenser and the absorber
- evaporator and the absorber
15: The dial of a pressure gauge, when installed on the high side of a system be graduated 1.2 times the designed pressure.
- True
- False
16: Class 3 refrigerants are
- non-toxic
- highly flammable
- non-flammable
- toxic
17: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
18: On cooling towers, what causes the condenser water to drop
- ambient temperatures
- tower fans
- sensible heat
- evaporation of the water droplets
19: To determine the pump size needed for an open cooling tower system, the following must be known,
- GPM and unbalanced head and friction head
- GPM and friction head
- GPM and balanced head and friction head
- GPM, pipe size, and equivalent head.
20: A 24 volt transformer with a 240 volt primary can handle how many amps?
- There isn't enough information to answer.
- 20 amps
- 10 amps
- 24 amps
21: On a centrifugal compressor, stationary diffuser vanes are needed to
- stop gas flow
- increase the clearance space
- prevent high pressure on the packing
- convert velocity energy to pressure
22: When should a relief valve start to function?
- At it's set pressure
- Two times it's working pressure
- Before the purge station discharges
- 10 psi before it's set pressure
23: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
- Latent heat
- Specific heat
- Sensible heat
- Enthalpy
24: If a purge unit fails on a low pressure chiller, what are the symptoms?
- low pressure chillers do not have purge units
- high head pressure
- low suction pressure
- increased capacity
25: What refrigerant were phased out in 2004?
- R-134a
- R-22
- R-12
- R-11