Topics: All categories in the pool
1: Ammonia vaporization takes place at what temperature?
- -32F
- -28F
- -110F
- -460F
2: 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
3: What are the three components of a transformer?
- Contacts, secondary coil, and core
- Primary core, secondary coil, and high and low voltage connectors.
- Primary coil, secondary coil, and core
- Primary coil, secondary coil, and copper contacts
4: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
- Nesting scrolls
- Rotating vanes
- Fan-like action
- Suction and discharge valves
5: A motor is rated for 120 volts and has a RLA (rated-load amps) of 5 amps. What is the wattage of the motor?
- 5KW
- 600 watts
- 746 watts
- 1000 watts
6: It takes how many BTU/hr to melt one pound of ice at 32F
- 212
- 180
- 970
- 144
7: Refrigerant piping crossing an open space that affords passageway in any building shall not be less than _____ feet above the floor unless piping is located against the ceiling.
- 9.00'
- 8'4"
- 7.00'
- 7.25'
8: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit
- 9.776 watts
- .9776 watts
- 9,776 watts
- 977.6 watts
9: On cooling towers, what causes the condenser water to drop
- tower fans
- ambient temperatures
- sensible heat
- evaporation of the water droplets
10: Emergency shutdown procedures, including precautions to be observed in case of a breakdown or leak over 55 lbs of refrigerant charge, shall be displayed on a conspicuous card located as near as possible to the
- boiler
- outside the machinery room
- compressor
- evaporator
11: Large Mercantile occupancy is a premise or that portion of a premise where more than ____ persons congregate on levels above or below the street level to purchase personal merchandise.
- 100
- 400
- 350
- 250
12: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
13: What would be the classification of a prison?
- Place of assembly
- Industrial
- Institutional
- Large mercantile
14: What is the refrigerant dichlorodifluoromethane?
- R-22
- R-123
- R-134A
- R-12
15: Doors communicating with outside from a mechanical room must be?
- Self-closing, approved, fire door
- Steel, approved, weather-stripped
- Self-closing, wooden, fire door
- Self-closing, aligned, fire door
16: By using nitrogen within a pipe during brazing operation,
- Exterior scale formation is minimized
- Copper oxide formation is prevented
- Discoloration is prevented
- The explosion hazard is confined
17: A motor starter is a device that includes an overload and a _______?
- contactor
- 2-pole contacts
- duel-coil
- all of the above
18: A class B1 refrigerant is considered
- non-toxic but highly flammable
- toxic but non-flammable
- toxic and somewhat flammable
- non-toxic and non-flammable
19: The purpose of an accumulator is to
- reduce friction loss to the flow of refrigerant
- assure no liquid returns to the compressor
- store excess refrigerant from the reciver
- filter out impurities from the system
20: Color is important in oil because
- allows you to see into crankcase
- it makes sight glasses easy to read
- can tell us something about the refining of oil
- it indicates the viscoisty.
21: Total heat of a substance is considered
- enthalpy
- sensible heat
- specific heat
- empathetical
22: Secondary refrigerants are usually
- Prestone anti-freeze
- alcohol
- expensive
- water or brine
23: Two capacitors are wired in parallel. One capacitor has a value of 15uf. The other has a value of 25uf. What is the total value supplied?
- 15 uf
- 20 uf
- 25 uf
- 40 uf
24: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
- pick up voltage
- lift voltage
- boost voltage
- run voltage
25: RPM's of a centrifugal compressor are at approximately?
- 500
- 30,000
- 10,000
- 15,000