Topics: All categories in the pool
1: What is considered a cooling agent?
- any liquid used for the transmission of heat without vaporization
- any liquid used for the transmission of heat without condensation
- any liquid used for the transmission of heat when condensation occur
- any liquid used for the transmission of heat when vaporization occurs
2: Before replacing a seized compressor, the _______ should be determinded.
- current draw
- designed head pressure
- cause of seizure
- type of refrigerant
3: A Category D fluid
- is when the fluid handled is non flammable, nontoxic, and not damaging to human as defined in ANSI/ASME Process Piping.
- is when the design pressure does not exceed 150 psi
- a fluid for service piping in which the potential for personnel exposure is judged to cause harm and irreversible damage to those persons exposed to it
- Both a and b are correct
4: In a system designed for sub-zero ambient temperatures, what must be added?
- Nitrogen
- Booster compressor
- Low-ambient kit
- Infrared dye for leak identification
5: 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
6: A crankcase heater has a supplied voltage of 100 volts and is drawing 1.4 amps. What is the resistance?
- 71 ohms
- 80 ohms
- 27 ohms
- 104 ohms
7: If a purge unit fails on a low pressure chiller, what are the symptoms?
- low pressure chillers do not have purge units
- low suction pressure
- high head pressure
- increased capacity
8: The start winding has _____ turns than the run winding.
- more
- less
- the same
- none of the above
9: 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
10: While the system is operating, the discharge line should be
- too hot to hold by hand
- at the same temperature as the crankcase
- 10-15F warmer than ambient
- room temperature
11: Trichlorofluoromethane is the name of what refrigerant?
- R-113
- R-502
- R-12
- R-11
12: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
13: What type of relief valve is used on low pressure centrifugal compressor systems?
- Spring-loaded relief valve
- Rupture disc
- Purge relief
- None of the above
14: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
- Class A machinery room
- Class B machinery room
- Class M machinery room
- Class T machinery room
15: When an inspection is needed, how often must it be done?
- every 36 months
- every 24 months
- annually
- every 18 months
16: Which of the following is NOT a positive displacement compressor?
- scroll
- reciprocating
- screw
- centrifugal
17: A premise where large numbers of people congregate and from which occupants can not quickly vacate the space is considered
- public assembly occupancy
- institutional occupancy
- commercial occupancy
- mixed occupancy
18: Which refrigerant replaced R-12?
- R-134A
- R-410A
- R-407A
- R-22
19: What type of relief valve is used on a CO2 system?
- glove disc
- fusible plug
- rupture disc
- gate valve
20: If a condenser is on a roof and the temperature is 35F and dropping the capacity
- decreases
- run as designed with low ambient controls
- doesn't change
- increases
21: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 255 psig
- 327 psig
- 125 psig
- 365 psig
22: Field Inspections of refrigeration and A/C systems in Massachusetts shall be made by
- District Engineering Inspectors
- Commissioned Inspectors
- Master licensed Technician
- both a or b
23: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 660 lbs
- 330 lbs.
- 55 lbs
- 550 lbs
24: What device should be used on low-temperature freezers?
- high capacity TXV
- discharge muffler
- hot-gas by-pass
- oil separator
25: What type of oil is used in R-410A systems?
- polyalkylene glycol (PAG)
- mineral oil
- polyolester (POE)
- naphthene