Topics: All categories in the pool
1: Who authorizes changes to the safety codes?
- Person in charge of the facility
- Contractor who last serviced the system.
- Person who pulled the permit
- Board of Boilers
2: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.
- 80%
- 75%
- 90%
- 99%
3: How are a compressor and condenser fan wired?
- parallel
- parallel-series
- series
- series-parallel
4: 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
5: On a ammonia compressor, the pressure of a forced fed oil pump is changed by varying the
- cooling temperature set-point
- opening at the pump inlet
- adjustment of the spring tension of the TXV
- opening at the pump outlet
6: Suction valve unloaders afford an effective means of
- refrigerant control
- evaporator control
- superheat control
- capacity control
7: Dew point is
- the temperature of air of 50% RH
- the temperature below which water vapor in the air will start to evaporate
- 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 condense
8: R-123 belongs to Group
- B-2
- B-3
- A-3
- B-1
9: 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.
10: copper and its alloys shall not be used in contact with _____ except as a component of bronze alloys for bearing or other non-refrigerant containing uses.
- Lithium bromide
- HCFC-123
- CFC-11
- ammonia
11: one BTU equals
- 31.4 hp
- 12,000 hp
- 3.41 hp
- Pi
12: The instrument used to measure the specific gravity of absorption chiller solutions is the
- Psychrometer
- anemometer
- hydrometer
- refractometer
13: The absorber shell contains the
- condenser, the evaporator, and the generator
- condenser and the generator
- condenser and the absorber
- evaporator and the absorber
14: What is the state of the refrigerant leaving the evaporator?
- a low temperature subcooled liquid
- a high temperature superheated vapor
- low temperature superheated vapor
- a high temperature subcooled liquid
15: How far from the ground does a relief valve need to be?
- At least 15' above grade
- Not more than 3' above grade
- At least 25' above grade
- At least 20' above grade
16: A micron is
- one thousandths of a millimeter
- one millonths of a micrometer
- a larger unit of measurement than Hg
- one millonths of a centimeter
17: How does a centrifugal compressor create the pressure differential needed to move refrigerant through the system?
- Rotating vanes
- Suction and discharge valves
- Nesting scrolls
- Fan-like action
18: A motor starter contains a thermal overload and a
- contactor
- solenoid
- transformer
- 3-way relay
19: The leaving chilled water set point for comfort cooling is typically?
- 60
- 45
- 38
- 66
20: A premise or that portion of a premise where people transact business, receive personal service, or purchase foods, other goods is considered a
- business occupancy
- public assembly occupancy.
- commercial occupancy
- mercantile occupancy
21: A hissing noise at the expansion valve is a good indication that
- gas is passing thru it
- liquid is passing thru it
- expansion valve is oversized
- nothing is passing thru
22: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- lost heat
- latent heat
- specific heat
- sensible heat
23: On a pumpdown system, the liquid-line solenoid is controlled by the
- thermostat
- low-ambient controller
- low pressure switch
- defrost timer
24: 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
25: The purpose of a receiver is
- a vessel to store refrigerant outside the system
- to increase the capacity that the system can hold
- to use a a later date
- all of the above