Topics: All categories in the pool
1: 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
2: The location of a thermal bulb of a TXV affects
- subcooling
- the amount of liquid returning to the compressor
- the amount of liquid refrigerant in the evaporator
- the amount of liquid in the condenser.
3: 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.
- 7.25'
- 9.00'
- 8'4"
- 7.00'
4: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Oil
- Electricity
- Air
- Heat
5: Capacity control on an absorption system is typically accomplished by varying the
- rate at which heat is supplied to the generator
- speed of the condenser water circulator pump
- speed of the chilled water circulatory pump
- pressure setting on the system's rupture disc
6: Refrigeration piping before being buried shall be
- leak tested
- encased in pipe duct
- pressure tested
- All of the above
7: A class B2 refrigerant is considered
- toxic and somewhat flammable
- non-toxic and highly flammable
- toxic and non-flammable
- non-toxic and non-flammable
8: 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
- evaporator
- outside the machinery room
- compressor
- boiler
9: Ammonia (NH3) is a group III refrigerant
- True
- False
10: 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
11: Megaohm meters can detect a ground in the
- up to 10,000 ohms
- up to 1,000,000 ohms
- 10,000,000 ohms or higher
- up to 1,000 ohms
12: A mercury bulb controller is not recommended for
- line or low voltage use
- line voltage use
- low voltage use
- use where vibration is severe
13: What is used to check very low air pressures in air conditioning duct?
- Barometer
- Anemomter
- Vacuum gauge
- Manometer
14: Capacitors are rated in
- volt - amperes
- megaohms
- kelvins
- micro-farads
15: Pressure relief devices are marked with a ____________ signifying compliance with the ASME Boiler & Pressure Vessel Code.
- UV or UR
- UL and UM
- UL and UR
- UM or UL
16: On a large centrifugal system, what meters the flow to the evaporator?
- TXV
- Low side float
- High side float
- Cap tube.
17: The actual expansion curve of compression follows most nearly which one of the following curves?
- Volume Temperature
- Isothermal
- Adiabatic
- Pressure Temperature
18: A pressure relief should be located at least _______ from windows and doors.
- 25'
- 15'
- 20'
- 30'
19: one BTU equals
- Pi
- 12,000 hp
- 31.4 hp
- 3.41 hp
20: What percentage of amperage difference is allowable phase to phase on a HVAC circuit phased to phase?
- 4%
- 1%
- 2%
- 25%
21: A motor is rated for 120 volts and has a RLA (rated-load amps) of 5 amps. What is the wattage of the motor?
- 746 watts
- 5KW
- 600 watts
- 1000 watts
22: What type of voltage cause a potential relay to open?
- 24 volt supply from the thermostat
- 120 volt line voltage
- Pick-up voltage
- none of the above
23: A compressor in which the increase in vapor pressure is attained without changing the internal volume of the compression chamber is called
- neutral chamber-type compressor
- non-positive displacement compressor
- negative displacement compressor
- non-volumetric displacement compressor
24: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use fusible plugs
- do not need pressure relief protection
- shall use pressure relief devices
- shall use pressure relief devices or fusible plugs
25: 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