Topics: All categories in the pool
1: 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
2: The main purpose of a refrigerant detector in a machinery room is to
- inform there is a refrigerant leak int he system
- detect toxins in the air caused by a refrigerant leak
- to set off an alarm when there is refrigerant present inside the room
- all of the above
3: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
- strong solution
- concentrated solution
- absorbed solution
- weak solution
4: Pressure vessels with an internal volume of 3 cubic feet or less
- shall use pressure relief devices
- do not need pressure relief protection
- shall use fusible plugs
- shall use pressure relief devices or fusible plugs
5: 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
6: What does an anemometer measure?
- temperature
- amperage
- voltage
- velocity
7: What would be the classification of a church?
- Large mercantile
- Place of assembly
- Industrial
- Institutional
8: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 6.6 lbs
- 44 lbs
- 13.9 lbs
- 22 lbs
9: 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
10: In an air conditioning plant which an indirect low side, water is used inside of bring: the proper sequence of operating the plan is
- start the comrpessor
- start the fan and circulating pump
- reset the expansion valve
- reset the safety valve
11: Gauge pressure is
- Barometric pressure
- Absolute pressrue
- Force of pressure above that of atmosphere
- Atmospheric pressure
12: NH3 is
- lithium bromide
- R-718
- ammonia
- R-508A
13: What is the temperature that a liquid and a vapor can exist in equilibrium called?
- Wet bulb temperature
- Saturated temperature
- Critical temperature
- Dry bulb temperature
14: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
15: Where a refrigeration or air conditioning system is installed,
- The company who installed the system must notify the fire department in the jurisdiction where installed
- A field inspection shall be made before it is put into service
- it shall not be operated below prescribed pressuers
- the form or certificate shall be authorized by the Department of Public Safety
16: 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
17: What is the maximum voltage range allowed on an electrical circuit?
- 10%
- 15%
- 20%
- 5%
18: "I" represents ____ in the Ohm's law formula.
- resistance
- amperage
- capacitance
- voltage.
19: What must be done to all doors and access points in duct work going through a mechanical room?
- Must be hindged
- Must be screwed shut
- Must be sealed and gasketed
- All of the above
20: Which of the following is a drop-in for R-22
- R-410A
- R-134A
- R407C
- None of the above
21: What is the typical air conditioning operating pressures for 410A?
- 60 psi suction, 210 psi discharge
- 25 psi suction, 125 psi discharge
- 105 psi suction, 350 psi discharge
- None of the above
22: What is the boiling point of refrigerant governed by?
- P&T relationship
- Condenser sub-cooling
- Compressor RPM's
- Evaporator temperature
23: A 3-cubic foot receiver must have what type of relief valve?
- fusible plug
- relief valve
- rupture device
- none of the above
24: When an A/C system is excessively low on refrigerant
- it can become contaminated with water
- there can be nuisance trip outs
- the suction line may be too hot to touch
- All of the above
25: What does safe access mean?
- Locked doors
- OSHA approved
- Well-lit exit signs
- A clear unobstructed path to the equipment and controls