Topics: All categories in the pool
1: At higher altitudes, boiling temperatures
- increase
- decrease
- are unaffected
- depends on the refrigerant
2: A machine room with a refrigerant system using ammonia shall
- be provided with a continuously operated ventilation system
- be considered a non-hazardous location in accordance with National Electrical code
- have no flame producing apparatus permanently installed and operated
- All of the above
3: A R-22 system running with a condensing temperature of 110F and a 40F evaporator temperature will read pressures of ____ on the high side and ____ on the low side.
- 455 psig, 185 psig
- 350 psig, 120 psig
- 257 psig, 77 psig
- 226 psig, 68 psig
4: In a properly balanced system with valves open and properly adjusted, if the suction line is warm to the touch, its because of
- low head pressure
- oil in evaporator
- moisture in the system
- not enough oil in the system
5: The heat picked up in the evaporator must equal to
- the heat lost by the medium being cooled
- the heat of compression
- the heat giving by the condenser
- the heat gained by the condenser
6: A thermometer inside a duct measures ____ heat.
- specific
- hidden
- latent
- sensible
7: Starting relays for a single phase compressors are used to remove the starting circuit from operation when the motor reaches approximately ____ percent of its speed.
- 50
- 100
- 75
- 24
8: Heat that changes the physical state of a substance without effecting a change in its temperature is known as
- sensible heat
- specific heat
- lost heat
- latent heat
9: A tachometer is an instrument used to measure
- air velocity
- speed
- static pressure
- RPM
10: Horizontal piping should be run level.
- True
- False
- No, unless the supervisor on the job says so.
- Yes, if the condenser is located above the evaporator
11: Pressure vessels of 10 cubic feet or more gross volume shall use
- at least one rupture member
- a dual pressure-relief valve if charging into the atmosphere
- at least three means of discharge and/or rupture discs
- both a and b are correct
12: The solution that leaves the concentrator in an absorption chiller is referred to as the
- strong solution
- diluted solution
- weak solution
- absorbed solution
13: A Low-Probability System
- is such that a leak of refrigerant from a failed connection can not enter the occupied space
- is such that a leak of refrigerant from a failed connection will enter the occupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is a system highly likely to leak form a failed connection or component of such system
14: Joints in refrigeration piping must be _____ before being covered?
- Pressurized
- Leak tested
- Insulated
- Inspected
15: What is the leaving chilled water set point for water chiller systems?
- 38F
- 55F
- 45F
- 66F
16: If the dry bulb temperature is 85F and the wet bulb temperature is 70F, the dew point temperature will be approximately (use psychometric chart)
- 77F
- 32F
- 58F
- 70F
17: R-410A can segregate in the system or chemically change its composition due to a leak.
- True
- False
18: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
- Machinery rooms need not be vented
- the mechanical room housing the refrigeration system
- the return air ducted system
- the outdoors
19: What is the voltage of each leg of a 480 Volt three-phase motor?
- 277v
- 208v
- 120v
- 240v
20: The freezing point of water at sea level is?
- 32C
- 32F
- 0F
- -10C
21: A split-phase motor has a ______ winding and a ____ winding
- run, common
- duel-run, duel-start
- start, common
- run, start
22: Where is the high-side float located on a chiller system?
- flash line
- inside the chiller barrel
- discharge line
- liquid line
23: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
24: What is an egress?
- A code violation
- A valve put on the low side of the system to prevent frosting
- An entrance or exit
- An escape route
25: Class A refrigerants are considered
- toxic
- flammable
- non-flammable
- non-toxic