Topics: All categories in the pool
1: What must be done to refrigerant pipes before being buried?
- Coated
- Encased
- Certified
- Leaked checked
2: Viscosity is
- a measure of heat content
- measure of weight
- the coefficient of external friction
- the ability of oil to flow
3: When air is ducted through a machine room that services occupied space, What must be done?
- Flanged and gasketed
- Insulated and cross broke
- Ducted and sealed
- Welded and seamed.
4: The best way to detect ammonia in brine is
- carbonation of soda
- nessler regaent
- CO2 gas
- potassium of line
5: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
6: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Low Pressure displacement
- Pressure induced displacement.
- Positive displacement
- Non-positive displacement
7: B3 refrigerants are considered
- toxic and highly flammable
- non-toxic but flammable
- toxic but non-flammable
- non-toxic but non-flammable
8: Field Inspections of refrigeration and A/C systems in Massachusetts shall be made by
- District Engineering Inspectors
- Commissioned Inspectors
- Master licensed Technician
- both a or b
9: In a horizontal shell & tube condenser, the ammonia is liquefied by
- passing thru the tubes from top to bottom
- removing the latent heat of vaporization
- water sprayed over condenser
- removing the latent heat of fusion
10: A device used to measure small pressure differences is the
- pyrometer
- phsycometirc
- anemometer
- manometer
11: What device measures the specific gravity of a substance?
- Manometer
- Thermometer
- Hydrometer
- Hygrometer
12: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?
- R-22
- R-113
- R-11
- R-12
13: What must be done to refrigerant pipes before being buried ?(8.10.4)
- Insulated and installed in a pipe duct (Encased)
- Leak checked
- Certified
- Classifed
14: What should never be used in pressure testing refrigeration systems?
- Oxygen
- Compressed air
- Nitrogen
- Both a and b
15: Before replacing a seized compressor, the _______ should be determinded.
- type of refrigerant
- current draw
- cause of seizure
- designed head pressure
16: The reversing valve is commonly used
- on multiple compressor systems
- on all heat pumps
- on commercial system that involve two different temperatures
- when the code requires a check valve
17: What type of fuses must be used on a HVAC system?
- TR Type, Duel Element, Time Delay
- Fast blow
- 10% lower than RLA
- none of the above
18: pressure relief valves must discharge to the atmosphere at a location not less than 15 feet from ground level and ____ feet from any window, ventilation opening, or exits of buildings.
- 25
- 15
- 20
- 10
19: There can be no airflow from an occupied space through a machine room unless what?
- System is high velocity
- System is ducted and sealed
- Duct is not located in the ceiling
- None of the above.
20: While water is evaporated in an evaporative condenser the impurities which were in the water are
- remain in the air
- washed out of the air by the spray pump
- blown to the atmosphere by the fan
- accumulate in the sump water
21: The start winding has _____ turns than the run winding.
- more
- less
- the same
- none of the above
22: Who approves containers for refrigerants?
- D.O.D
- E.P.A
- D.O.T
- D.O.E
23: A 50 VA control transformer with a 25 volt control output would be rated for _________ amps.
- 1250
- 2
- There isn't enough information to answer.
- 2.5
24: How much clearance do you need around the perimeter of electrical panels?
- 36"
- 12"
- 18"
- 24"
25: In an air conditioning system, the unit of total heat energy content in an air/vapor mixture is
- Latent heat
- Specific heat
- Enthalpy
- Sensible heat