Topics: All categories in the pool
1: High side floats are used on centrifugal chiller systems are are considered critically charged systems.
- False
- are obsolete.
- depends on the type of refrigerant being used
- True
2: Where is the high-side float located on a chiller system?
- flash line
- liquid line
- inside the chiller barrel
- discharge line
3: The high side float assembly meters refrigerant into the evaporator through the
- upper chamber of the low side
- upper chamber of the high side
- lower chamber of the low side
- lower chamber of the high side
4: A positive displacement compressor is
- is a reciprocating type compressor with 2 or more pistons
- a compressor in which the increase in pressure is attained by changing the internal volume of the compression chamber
- where the compressor's suction pressure and the compressor;s discharge pressure is more than 50 PSI
- a compressor in which the increase in pressure is attained by changing the internal pressure of the compression chamber
5: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code
- licensed technician
- licensed welder
- competent welder
- welder qualified
6: A high side float is a
- metering device used on critically charged systems that controls the level of the liquid refrigerant in the high pressure side of the system.
- float type switch that stops the compressor when the pressure on the high side becomes too high
- float type valve that controls the amount of refrigerant stored in the receiver
- float type valve that controls the crankcase oil level
7: If the suction pressure is low and the evaporator temperature high, the cause will be a?
- compressor suction valve stuck open
- overcharged
- too small evaporator
- starved evaporator
8: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
- the outdoors
- the mechanical room housing the refrigeration system
- Machinery rooms need not be vented
- the return air ducted system
9: A rule of thumb in air conditioning is ____ CFM per ton?
- 100
- 500
- 600
- 400
10: The purpose of an accumulator is to
- filter out impurities from the system
- reduce friction loss to the flow of refrigerant
- store excess refrigerant from the reciver
- assure no liquid returns to the compressor
11: Oils, classified as to source, are
- naphthalene, paraffin, and castor
- animal, vegetable, and mineral
- animal, vegetable, and castor
- naphthalene, mixed, and paraffin
12: A declaration test is needed when the system contains more than
- 65 lbs
- 55 lbs
- 110 lbs
- 120 lbs
13: Setting a pressure relief device shall not exceed ___ of the design pressure
- 80%
- 90%
- 100%
- 75%
14: 1 Watt = ______ BTU's?
- 7.216
- 3.412
- 12
- 4.482
15: Which of the following most closely represents the concentration of Li-Br in a absorption system?
- 60% Li-Br, 40% distilled water
- 40% Li-Br, 60% tap water
- 40% Li-Br, 60% distilled water
- 50% Li-Br, 50% tap water
16: A halide torch is most useful with a freon compression system
- to detect refrigeration leaks in piping joints
- to release a sticking valve
- to remove from from TXV's and evaporator coils
- to sweat flanges on the refrigeration piping
17: What are the three components of a transformer?
- Primary core, secondary coil, and high and low voltage connectors.
- Primary coil, secondary coil, and copper contacts
- Contacts, secondary coil, and core
- Primary coil, secondary coil, and core
18: What section governs pressure vessels?
- Section 1 ASHREA 15 ASME fired
- Section 8 ASHREA 15 ASME unfired
- OSHA
- Section ASHREA 34
19: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
20: Gauge pressure is
- Atmospheric pressure
- Absolute pressrue
- Barometric pressure
- Force of pressure above that of atmosphere
21: Bubbles in the liquid line sight glass could be caused by
- leaking discharge valves in the compressor
- bad low pressure switch
- overcharge of oil
- plugged drier
22: Secondary refrigerants are usually
- Prestone anti-freeze
- expensive
- water or brine
- alcohol
23: A compressor that increases vapor pressure by changing the internal volume of the compression chamber is called?
- Non-positive displacement
- Low Pressure displacement
- Pressure induced displacement.
- Positive displacement
24: A device used to measure small pressure differences is the
- anemometer
- pyrometer
- manometer
- phsycometirc
25: NH3 is
- R-718
- ammonia
- R-508A
- lithium bromide