Topics: All categories in the pool
1: 1 HP = ____ Watts?
- 746
- 3.1416
- 3,412
- 11,239
2: The heat picked up in the evaporator must equal to
- the heat gained by the condenser
- the heat of compression
- the heat lost by the medium being cooled
- the heat giving by the condenser
3: Low ambient controls are used when
- on air conditioning systems only
- always
- economizers are used
- when systems run all year round
4: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
5: The actual expansion curve of compression follows most nearly which one of the following curves?
- Isothermal
- Adiabatic
- Volume Temperature
- Pressure Temperature
6: The Board of Boilers adopts by reference
- MSCA Code
- the 1997 ANSI/ASHRAE Safety Code
- the MACS Pressure Vessel Code of Massachusetts
- Montreal Protocol Safety Code
7: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or more
- vessels of 3 cubic feet or more
- vessels of 3 cubic feet or less
- vessels of 10 cubic feet or less
8: At higher altitudes, boiling temperatures
- are unaffected
- decrease
- increase
- depends on the refrigerant
9: How can you test mechanical strength of an electrical connection?
- measure ohms with an electrical meter
- measure voltage across the connection
- attempt to pull the wire from the connector by hand
- none of the above.
10: R-22 falls under which safety classification?
- B-1
- B-2
- A-2
- A-1
11: How are a compressor and condenser fan wired?
- parallel-series
- series-parallel
- parallel
- series
12: Booster compressors connect to the ____ side of the compressor
- liquid
- oil side
- vapor
- low side
13: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- red
- green
- orange
- blue
14: When air is ducted through a machine room that services occupied space, What must be done?
- Insulated and cross broke
- Flanged and gasketed
- Welded and seamed.
- Ducted and sealed
15: Which is the lowest vacuum?
- 10 psia
- 1,000 Microns
- 5" hg
- 5 psig
16: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 365 psig
- 255 psig
- 125 psig
- 327 psig
17: What is a Category "M" fluid?
- A fluid which is nonflammable, nontoxic, not damaging to human tissues, does not exceed 150 psig, and the designed temperature is between -20F to 366F
- A typical refrigerant used on newer air conditioning and heat pump systems
- Any fluid that exceeds 150 psig and has design temperatures over 366F
- A toxic fluid, which can produce serious irreversible harm to persons on breathing or bodily content
18: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Electricity
- Oil
- Air
- Heat
19: If the compression ratio on a centrifugal compressor rises too high, the compressor will stop pumping and make a loud sound commonly referred to as a
- merge
- splurge
- surge
- purge
20: _____ alloys shall not be used in contact with an halogenated refrigerants.
- Zinc
- Nickel
- Magnesium
- Copper
21: A low oil switch is typically
- non used on semi-hermetic compressors over 10 ton capacity
- automatic reset
- time-delay auto reset
- manual reset
22: What type of pressure relief device is used on a CO2 system?
- Glove valve
- Fusible plug
- Rupture disk
- Gate valve
23: R-717 is
- carbon dioxide
- water
- ammonia
- trichloromethane
24: The measurement of heat in a particular substance is
- specific heat
- latent heat
- sensible heat
- enthalpy
25: All electrical work done on refrigeration systems must comply with
- NEC and Massachusetts Modifications
- OSHA
- Department of Energy
- ASHREA-15 Section 9.2.1