Topics: All categories in the pool
1: Direct systems using Group II refrigerants
- shall be installed in Class T machinery rooms
- shall be allowed to be used for human comfort.
- shall not be used for air condition for human comfort
- shall be installed per instruction of the AHJ
2: Which of the following is a drop-in for R-22
- R-410A
- R-134A
- R407C
- None of the above
3: R-717 is
- water
- carbon dioxide
- ammonia
- trichloromethane
4: Which refrigerant(s) is an HFC?
- R-22
- R-410A
- R-502
- All of the above
5: Pressure vessels nameplate markings must be compliant with the
- ASHRAE 34 Standards
- CMR-588 & CMR-528
- ASME Boiler and Pressure Vessel Code
- All of the Above
6: When a receiver is greater than 3 cubic feet but less than 10 cubic feed, what is the minimum relief device required?
- fusible plug
- relief valve
- rupture disc
- all of the above
7: One watt of electrical energy in a resistive heater will provide _____ BTU/hr
- 6.830
- 3.415
- 16.64
- 34.15
8: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Electricity
- Heat
- Air
- Oil
9: The low pressure oil safety switch
- resets itself automatically
- resets itself after the time delay has terminated
- never trips
- must be reset manually
10: Adjusting the spring pressure on a TXV
- changes subcooling
- changes superheat
- makes no difference
- adjusts the bulb charge
11: A pressure relief should be located at least _______ from windows and doors.
- 20'
- 15'
- 30'
- 25'
12: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
- 50.2 psig
- 66.1 psig
- 70.8 psig
- 43.3 psig
13: Heat transferred by conduction from one body to another is done
- via radiation
- via solids
- via liquids
- via heat rays
14: Which oil is hydoscopic?
- mineral
- polyolester
- SW30
- animal
15: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.
- low pressure
- critical pressure
- high pressure
- design pressure
16: Three-phase motors have what type of windings?
- three start windings
- one start winding and one run winding.
- three run windings and 3 start windings
- three run windings
17: Suction line oil traps should be installed when the condenser is
- in the basement and the evaporator is on the third floor
- more than 100' away from the evaporator
- on the third floor roof and the evaporator is in the basement
- located outside the operates in temperatures below 35F
18: All welding done on any refrigeration system or piping covered by 522 CMR 9.00 shall be performed by a according to Section IX of the ASME code
- competent welder
- welder qualified
- licensed welder
- licensed technician
19: The ASHRAE Standard 34 requires what type of alarm for equipment rooms using HCFC-123?
- A group sensing
- phosgene gas sening
- CO Sensing
- refrigerant sensing
20: Which winding have the most turns?
- Start
- they have equal amount of turns
- run
- depends on the motor phase
21: The principle used in continuous type absorption systems is
- Charles's Law
- Boyle's Law
- Dalton's Law
- Ohm's Law
22: The level of voltage caused by back electromagnetic force that opens the contacts of a potential relay in order to take the start capacitor out of the circuit is
- run voltage
- pick-up voltage
- boost voltage
- lift voltage
23: Refrigerant systems containing Group I refrigerants can be installed in or on public stairways.
- True
- False
24: Pressure-limiting device isn't required on a factory-sealed system containing less than ____ lbs.
- 18
- 33
- 50
- 22
25: Emergency shutdown procedures, including precautions to be observed in case of a breakdown or leak over 55 lbs of refrigerant charge, shall be displayed on a conspicuous card located as near as possible to the
- evaporator
- outside the machinery room
- compressor
- boiler