Topics: All categories in the pool
1: The evaporator is a device to
- Keep the compressor busy
- store liquid refrigerant
- remove heat from the refrigeration system
- absorb heat into the refrigeration system
2: A low oil switch is typically
- time-delay auto reset
- manual reset
- non used on semi-hermetic compressors over 10 ton capacity
- automatic reset
3: A chilled water pump suction gauge reads 10 psig. Discharge gauge reads 48 psig. The head in feet of the pump is working against
- 116
- 38
- 108
- 88
4: Low ambient controls are used when
- economizers are used
- on air conditioning systems only
- always
- when systems run all year round
5: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
6: When testing systems using non-positive displacement compressors, the entire system shall be considered for test purposes as the low side.
- True
- False
7: The instrument used to measure the specific gravity of absorption chiller solutions is the
- refractometer
- hydrometer
- Psychrometer
- anemometer
8: What type of refrigerants are NOT flammable?
- CHC
- HFC
- HCFC
- All of the above
9: Suction line oil traps should be installed when the condenser is
- more than 100' away from the evaporator
- located outside the operates in temperatures below 35F
- in the basement and the evaporator is on the third floor
- on the third floor roof and the evaporator is in the basement
10: Mercury was used in thermometers primarily because it
- expands uniformly
- vaporizes at very high temperatures
- was inexpensive
- never freezes
11: 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
12: Pressure vessels of 10 cubic feet or more gross volume shall use
- at least one rupture member
- a dual pressure-relief valve if charging into the atmosphere
- at least three means of discharge and/or rupture discs
- both a and b are correct
13: The dial of a pressure gauge, when installed on the high side of a system be graduated 1.2 times the designed pressure.
- True
- False
14: The first step in mechanical refrigeration is
- condensation
- evaporation
- compression
- expansion
15: What is R-22?
- Chlorofluoromethane
- HFC
- Chlorodifluoromethane
- CCFCM
16: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
- Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
- over pressure protection
- over pressure protection and a rupture disc
- over pressure protection as well as a temperature protection device
17: Instead of using a compressor, an absorption air-conditioning chiller uses which of the following as its driving force?
- Oil
- Electricity
- Air
- Heat
18: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
- the low-pressure side of the system
- the high side of the system
- the liquid receiver
- both a and c are correct
19: What refrigerant doesn't have to be classifted?
- R-134a
- R-718
- R-711
- R-717
20: Calculate the voltage in a series circuit when the total amperage is 10 amps and the resistors have values of: R1=12 ohms, R2=8 ohms, R3=4 ohms
- 2,400 volts
- 24.0 volts
- 2.40 volts
- 240 volts
21: Which refrigerant was still able to be vented to the atmosphere after July 1, 1992?
- R-22
- R-11
- R-12
- R-113
22: What type of relief valve is used on a CO2 system?
- rupture disc
- gate valve
- glove disc
- fusible plug
23: Gauge pressure is
- Absolute pressrue
- Force of pressure above that of atmosphere
- Atmospheric pressure
- Barometric pressure
24: What is Trichlorotrifluoromethane?
- R-11
- R-12
- R-113
- R-13
25: If the power element of an expansion valve should lose its charge the valve would
- go closed
- underfeed the evaporator
- overfeed the evaporator
- go open