Topics: All categories in the pool
1: 14.7 psia is equivalent to
- atmospheric pressure at seal level
- 29.92" Hg
- 0 psig
- All of the above.
2: A 3-cubic foot receiver must have what type of relief valve?
- fusible plug
- relief valve
- rupture device
- none of the above
3: The maximum permissible amperage draw for a 40VA transfomer with a secondary voltage of 24V is
- 1.7
- 1.2
- .8
- .1
4: A R-410A system running with a condensing temperature of 110F and 50F evaporator temperature will read pressures of ___ on the high side and ___ on the low side
- 365 psig, 120 psig
- 455 psig, 185 psig.
- 226 psig, 68 psig
- 257 psig, 77 psig
5: Machinery rooms must be vented to ______?
- outdoors
- neutralizing tank
- basement
- unoccupied spaces
6: What refrigerant is an inorganic compound?
- R-132A
- R-22
- R-410A
- Ammonia
7: If a halide torch is used for leak detection, what color is the flame if it detects a leak?
- red
- blue
- green
- orange
8: Suction line oil traps should be installed when the condenser is
- on the third floor roof and the evaporator is in the basement
- in the basement and the evaporator is on the third floor
- more than 100' away from the evaporator
- located outside the operates in temperatures below 35F
9: Group A2 refrigerants have a ______ toxicity rating than Group B1 refrigerants.
- the same
- there is no Group B1 refrigerants
- lower
- higher
10: When the compressor is below the condensor
- traps are needed on the discharge line
- traps are not needed on this type of system
- traps are needed on the oil return line
- traps are needed on the suction line
11: What does an anemometer measure?
- temperature
- velocity
- voltage
- amperage
12: Low ambient controls are used when
- when systems run all year round
- always
- economizers are used
- on air conditioning systems only
13: It shall be the duty of the person in charge of the premises on which a refrigeration system containing more than ___ lbs of refrigerant is installed to provide a schematic drawing or panel giving directions for the operation of the system.
- 15
- 55
- 50
- 75
14: On a TXV, the purpose of an external equalizer is to?
- Increase the pressure on the top of the power head diaphragm
- balance the evaporator load
- compensate for a pressure drop across the evaporator coil
- allow a greater adjustment spam
15: Ammonia is under what safety classification?
- B1
- B3
- A3
- B2
16: When a refrigeration or air conditioning system is installed
- the form of certificate shall be authorized by the Department of Pubic safety
- it shall not be operated below prescribed pressures
- it shall be approved by the owner for proper operation.
- a field inspection shall be made before it is put into service
17: The External equalizer of a TXV compensates for
- pressure drop across the condenser coil
- pressure within the system
- pressure within the evaporator
- pressure drop across the evaporator coil
18: A mercury bulb controller is not recommended for
- use where vibration is severe
- low voltage use
- line or low voltage use
- line voltage use
19: Which of the following are considered inorganic refrigerants?
- R-717 and R-718
- 410A and R-407C
- R-500 and R-502
- None of the above
20: It takes how many BTU/hr to melt one pound of ice at 32F
- 144
- 212
- 180
- 970
21: Walls and doors of a machinery room shall be at least _____ hour(s) fire rated.
- 2
- 3
- 1
- 5
22: What is Trichlorotrifluoromethane?
- R-12
- R-13
- R-113
- R-11
23: If two 500 ohm resistors are connected in series, the resistance will be
- 500 ohms
- 200 ohms
- 1000 ohms
- 20 ohms
24: Setting a pressure relief device shall not exceed ___ of the design pressure
- 80%
- 100%
- 75%
- 90%
25: What do you need to do when you install a new system?
- Add refrigerant
- Document the superheat and subcooling reading
- Have it inspected
- Insulate the suction line before you take a superheat reading