Topics: All categories in the pool
1: Bubbles in the liquid line sight glass could be caused by
- bad low pressure switch
- leaking discharge valves in the compressor
- plugged drier
- overcharge of oil
2: By using nitrogen within a pipe during brazing operation,
- Copper oxide formation is prevented
- Discoloration is prevented
- The explosion hazard is confined
- Exterior scale formation is minimized
3: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- sensible heat
- specific heat
- latent heat
- lost heat
4: How would you know if there was a loss of crankcase pressure?
- oil will thin out
- oil will foam
- oil will thicken
- oil level will rise
5: The formula for Pure Power in a resistance circuit is
- Watts X amps.
- Watts = volts X amps
- Kw = volts X amps
- Watts X power factor
6: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
- does not require a pressure-limiting device
- shall have a pressure limiting device installed on the high side of the system
- shall be inspected by the Boiler of Inspectors bi-annually
- shall have a pressure limiting device and a pressure relief valve installed
7: A positive displacement compressor is
- a compressor in which the increase in pressure is attained by changing the internal volume of the compression chamber
- a compressor in which the increase in pressure is attained by changing the internal pressure of the compression chamber
- where the compressor's suction pressure and the compressor;s discharge pressure is more than 50 PSI
- is a reciprocating type compressor with 2 or more pistons
8: When the compressor is below the condensor
- traps are needed on the suction line
- traps are needed on the oil return line
- traps are needed on the discharge line
- traps are not needed on this type of system
9: Halogenated refrigerants cannot be used with what material?
- Stainless steel
- Magnesium alloy
- Aluminum
- Copper
10: Class 3 refrigerants are
- non-toxic
- non-flammable
- highly flammable
- toxic
11: How far from the window does a relief valve need to be according to ASHRAE-15?
- At least 20'
- At least 40'
- There is no minimum for relief valve and windows.
- At least 30'
12: A mercury bulb controller is not recommended for
- line voltage use
- use where vibration is severe
- line or low voltage use
- low voltage use
13: What type of relief valve is used on a CO2 system?
- rupture disc
- fusible plug
- gate valve
- glove disc
14: The proper location for an oil separator is between the
- compressor and condenser
- condenser and receiver
- evaporator and compressor
- receiver and metering device
15: Dual-pressure relief devices should be installed on
- vessels of 10 cubic feet or more
- vessels of 3 cubic feet or less
- vessels of 3 cubic feet or more
- vessels of 10 cubic feet or less
16: All low-pressure chillers use which type of compressor?
- Scroll
- Reciprocating
- Rotary
- Centrifugal
17: Relief valves are rated in
- pounds of air per hour
- gallons of water per minute
- gallons of water per hour
- pounds of air per minute
18: Setting a pressure relief device shall not exceed ___ of the design pressure
- 90%
- 100%
- 75%
- 80%
19: 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
20: The best way to detect ammonia in brine is
- potassium of line
- carbonation of soda
- nessler regaent
- CO2 gas
21: All electrical work done on refrigeration systems must comply with
- ASHREA-15 Section 9.2.1
- NEC and Massachusetts Modifications
- OSHA
- Department of Energy
22: What refrigerant has zero ozone depletion
- HFC
- CFC
- HCFC
- None of the above
23: What section governs pressure vessels?
- Section 1 ASHREA 15 ASME fired
- OSHA
- Section ASHREA 34
- Section 8 ASHREA 15 ASME unfired
24: An electrical circuit has a 208V power supply and draws 47 amps total, What would be the wattage of the circuit
- 977.6 watts
- 9.776 watts
- 9,776 watts
- .9776 watts
25: B3 refrigerants are considered
- toxic but non-flammable
- non-toxic but flammable
- non-toxic but non-flammable
- toxic and highly flammable