Topics: All categories in the pool
1: On a large centrifugal system, what meters the flow to the evaporator?
- Low side float
- Cap tube.
- TXV
- High side float
2: A 3-cubic foot receiver must have what type of relief valve?
- fusible plug
- relief valve
- rupture device
- none of the above
3: A secondary coolant is defined as
- a low temperature refrigerant used for cascading systems
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- any refrigerant direcly in contact with the cooling space for process cooling
4: 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
5: 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
- compressor
- boiler
- outside the machinery room
- evaporator
6: What must be done if refrigeration lines pass through a concrete floor?
- insulated
- installed through a pipe casing
- leak checked
- moisture barrier
7: R-22 is classified as a ____ refrigerant on the safety matrix.
- A-2
- B-1
- B-2
- A-1
8: What refrigerant doesn't have to be classifted?
- R-134a
- R-718
- R-717
- R-711
9: On a TXV, the purpose of an external equalizer is to?
- Increase the pressure on the top of the power head diaphragm
- allow a greater adjustment spam
- compensate for a pressure drop across the evaporator coil
- balance the evaporator load
10: Ammonia can come in contact with _______ ?
- Brass
- Copper
- Aluminum
- Copper tubing
11: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of
- moisture in the system
- not enough oil in the system
- low head pressure
- oil in evaporator
12: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
13: A movie theater would be considered a
- commercial occupancy
- institutional occupancy
- mixed occupancy
- public assembly occupancy
14: A class B2 refrigerant is considered
- non-toxic and highly flammable
- toxic and somewhat flammable
- toxic and non-flammable
- non-toxic and non-flammable
15: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
16: B3 refrigerants are considered
- toxic but non-flammable
- non-toxic but flammable
- non-toxic but non-flammable
- toxic and highly flammable
17: The absorber shell contains the
- condenser, the evaporator, and the generator
- condenser and the absorber
- evaporator and the absorber
- condenser and the generator
18: If the spring is adjusted to increase the superheat, this new setting will
- shorten the frost line
- lengthen the frost line
- allow more liquid into the evaporator
- have no effect on the frost line
19: All electrical work done on refrigeration systems must comply with
- ASHREA-15 Section 9.2.1
- NEC and Massachusetts Modifications
- OSHA
- Department of Energy
20: Group A3 refrigerants have a ______ flammability rating than Group B1 refrigerants
- the same
- lower
- higher
- there is no Group B1 refrigerants
21: Excessive head pressure is often caused by
- air cooled condenser is plugged
- insufficient refrigerant
- leaking reed valve on the discharge side
- thermostat set too high
22: The evaporator is a device to
- remove heat from the refrigeration system
- store liquid refrigerant
- Keep the compressor busy
- absorb heat into the refrigeration system
23: What is the voltage of each leg to ground of a three-phase motor with a 460v supply voltage?
- 120v
- 208v
- 240v
- 277v
24: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- orange
- red
- blue
- green
25: A VRF system is a direct system
- true
- false