Topics: All categories in the pool
1: The location of the thermal bulb for the TXV on the evaporator effects
- both the pressure and temperature in the feeler bulb
- the amount of superheat required to operate the TXV
- the amount of liquid in the evaporator
- the amount of gas in the evaporator
2: Halogen refrigerants are corrosive to which type of metal?
- copper
- black iron
- stainless steel
- magnesium
3: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
4: Liquid level gauge glasses shall have automatic closing shut off valves, except Bull's eye or reflex type.
- True
- False
5: A split-phase motor has a ______ winding and a ____ winding
- run, start
- run, common
- start, common
- duel-run, duel-start
6: R-123 belongs to Group
- B-2
- B-1
- B-3
- A-3
7: How are safety controls wired in a circuit?
- Series/parallel
- Either series or parallel
- Series
- Parallel
8: 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.
9: A premise where large numbers of people congregate and from which occupants can not quickly vacate the space is considered
- institutional occupancy
- mixed occupancy
- public assembly occupancy
- commercial occupancy
10: Trichlorofluoromethane is the name of what refrigerant?
- R-12
- R-113
- R-11
- R-502
11: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
- the mechanical room housing the refrigeration system
- the return air ducted system
- Machinery rooms need not be vented
- the outdoors
12: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the
- opening at the pump outlet
- cooling temperature set-point
- adjustment of the spring tension of the TXV
- opening at the pump inlet
13: What is specific heat?
- measured heat
- heat required to raise the temperature of 1lb of a substance 1 degree
- the specific heat required to change the state of one cubic foot of air to steam
- none of the above
14: High pressure controls should be set no higher than
- 25% of set point
- 10% of set point
- 80% of set point
- 90% of set point
15: Materials used in construction and installation materials used in the manufacture or installation of refrigerating equipment shall be suitable for conveying refrigerant and the refrigerant oils and will not deteriorate in the presence of what?
- Water and soap
- Moisture and air
- Air and dirt
- Oil and water
16: Suction valve unloaders afford an effective means of
- refrigerant control
- evaporator control
- superheat control
- capacity control
17: How many gallons of water per pound of ammonia do you need?
- 1
- 20
- 15
- 5
18: A secondary coolant is defined as
- any liquid used for the transmission of heat without a change of state in A/C refrigeration systems having flash point above 150F
- any refrigerant direcly in contact with the cooling space for process cooling
- a combination of interconnected parts from a closed circuit in where fluid is circulated for the purpose of cooling for a refrigeration system.
- a low temperature refrigerant used for cascading systems
19: Pairs of mating stop valves that allow sections of a system to be joined before opening these valves or separated after closing them are
- king valves
- companion or block valves
- gate or globe valves
- ball valves
20: What is R-22?
- Chlorofluoromethane
- CCFCM
- Chlorodifluoromethane
- HFC
21: Dew point is
- the temperature of air of 50% RH
- the temperature below which water vapor in the air will start to condense
- the temperature above which water vapor in the air will start to condense
- the temperature below which water vapor in the air will start to evaporate
22: The solution that leaves the concentrator in an absorption chiller is referred to as the
- strong solution
- weak solution
- diluted solution
- absorbed solution
23: The heat picked up in the evaporator must equal to
- the heat giving by the condenser
- the heat lost by the medium being cooled
- the heat gained by the condenser
- the heat of compression
24: A relief valve discharge capacity is rated in
- temperature minus pounds of air per second divided by release rate squared
- PSIA
- PSIG
- Pounds of air per minute.
25: A tachometer is an instrument used to measure
- RPM
- speed
- static pressure
- air velocity