Topics: All categories in the pool
1: "I" represents _______ in the Watt's law formula.
- amperage
- watts
- voltage
- reactance
2: Usually dry bulb temperature is
- higher than wet bulb temperature
- lower than dry bulb temperature
- same as wet bulb temperature
- not important and shall be ignored
3: Aluminum, Zinc, Magnesium, or their alloys shall not be used in contact with
- R-718
- methyl chloride
- ammonia
- trichlorotrifluoromethane
4: The 522 CMR 9.00 has adopted for reference ASHRAE ____
- III
- 10
- 15
- 25
5: A factory-sealed system containing less than 22lbs. of Group A1 refrigerant
- shall have a pressure limiting device and a pressure relief valve installed
- does not require a pressure-limiting device
- shall have a pressure limiting device installed on the high side of the system
- shall be inspected by the Boiler of Inspectors bi-annually
6: 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
7: Sensible heat is the heat added to a substance to
- change its state
- cause evaporation
- raise its temperature
- freeze it
8: Each machinery room shall contain
- a toxicity detector where the presence of ammonia or lithium bromide from a leak will concentrate
- smoke and fire alarms as well as three means of egress and that egress must meet 528 CMR ventilation requirements
- high and low pressure controls
- a refrigerant detector located in an area where the refrigerant from a leak will concentrate
9: Which oil is hydoscopic?
- SW30
- animal
- polyolester
- mineral
10: R-11 belongs to Group
- B-1
- A-1
- A-2
- B-3
11: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- High head pressure and low suction pressure
- Low head pressure and high suction pressure
- Low suction pressure and low discharge pressure
- High suction pressure and high discharge pressure.
12: The test pressure applied to the high side of each factory-assembled refrigerating system shall be at least equal to the design pressure of
- 2.5 times the design pressure
- the high side
- the low side
- the aggregate of the high side and low side
13: What does “ultimate strength” mean?
- Design strength of the vessel or piping in a refrigeration system
- Stress at which rupture will occur
- Highest or design pressure allowed inside a machinery room
- None of the above
14: What pipe can not be used for refrigeration?
- M
- K
- N
- L
15: The amount of heat required to raise the temperature of 1 lb of water 1F is?
- The rate of conduction
- 1 Therm
- 1 Kelvin
- 1 BTU
16: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
17: Before you change the type of refrigerant in a refrigeration system, what three things must be done?
- make sure it's compatible, notify owner, notify A.H.J
- you can't change refrigerants
- place sign, check for leaks, insulate
- nothing must be done
18: All low-pressure chillers use which type of compressor?
- Rotary
- Scroll
- Reciprocating
- Centrifugal
19: R-410A can segregate in the system or chemically change its composition due to a leak.
- True
- False
20: How many groups of refrigerants are there?
- 1
- 3
- 5
- 7
21: The actual expansion curve of compressor follows most nearly which one of the following
- Pressure-Temperature
- Volume
- Isothermal
- Adiabatic
22: A relief valve shall be located at least ___ above grade.
- 36'
- 25'
- 15'
- 10'
23: How many refrigerant classifications are there for flammability?
- 7
- 3
- 2
- 1
24: "R" represents ___ in the Ohm's law formula
- voltage
- amperage
- capacitance
- resistance
25: How many volts would you read on a 480V system phase to phase?
- 0
- 1/3 the voltage
- 480
- 277