Topics: All categories in the pool
1: When this is installed on the high side of a system, it must be capable of reading 1.2 times the design pressure (ASHRAE 15 9.11.3)
- Pressure gauge
- Temperature gauge
- Sight glass gauge
- All of the above
2: What is not a requirement of a Class T machine room?
- Self-closing doors
- Fire hose connected to the building fire protection system.
- Automatic ventilation
- Tight fitting doors
3: How many flammability classifications are refrigerants in?
- 5
- 3
- 7
- 2
4: Where is an EPR valve located on a multi-evaporator system?
- Suction line prior to the accumulator of the lowest temperature system
- Suction line at the compressor
- Suction line of the warmest evaporator
- Suction line of the coolest evaporator
5: The main cause of enacting the "no vending rule" of July 1st 1992 was
- global warming potential
- ozone depletion
- both a & b
- None of the above
6: 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
7: A direct system
- is on where brine is cooled & circulated to the space refrigerated
- is a self-contained complete factory made and tested system
- is one which encloses a separate body of evaporative refrigerant
- is where the refrigerant comes in contact with the space refrigerated
8: In a motor, an internal overload might open if
- there's a direct short
- there's an open start winding
- there's an excess current draw through the motor
- there was a high pressure refrigerant was used for a low pressure system.
9: The generator shell contains the
- evaporator and the absorber
- condenser and the generator
- condenser, the evaporator, and the generator
- condenser and the absorber
10: What's the purpose of a megahmmeter?
- To measure low to very low resistance values
- To alternate the current in a DC circuit in order to calculate the total impedance of a circuit
- To measure very high resistances
- None of the above
11: Sensible heat is the heat added to a substance to
- freeze it
- cause evaporation
- raise its temperature
- change its state
12: Pressure vessels with an internal volume of 3 cubic feet or less
- do not need pressure relief protection
- shall use pressure relief devices or fusible plugs
- shall use pressure relief devices
- shall use fusible plugs
13: A relief valve discharge capacity is rated in
- Pounds of air per minute.
- PSIA
- PSIG
- temperature minus pounds of air per second divided by release rate squared
14: Stop valves shall not be permitted between the system and the
- condenser
- service valve
- relief valve
- bleed valve
15: What type of oil is used in R-410A systems?
- polyalkylene glycol (PAG)
- naphthene
- mineral oil
- polyolester (POE)
16: Pressure limiting devices are not required for systems containing less then ________ refrigerants.
- 44 lbs
- 13.9 lbs
- 22 lbs
- 6.6 lbs
17: Mercury was used in thermometers primarily because it
- was inexpensive
- expands uniformly
- never freezes
- vaporizes at very high temperatures
18: Can ammonia be used on domestic system?
- yes, for systems under 10 tons
- no, unless there is proper ventilation system installed
- yes
- no
19: A line voltage thermostat controls a 1,200 watt strip header at 120 volts. What must be minimum ampere rated of the stat be?
- 10 amps
- 15 amps
- 5 amps
- 20 amps
20: R-123 belongs to Group
- A-3
- B-1
- B-3
- B-2
21: Where must a refrigeration contractor's license number be displayed?
- Trucks, license plates, and uniforms
- Truck, office, every job, and on all equipment
- Trucks, invoices, and advertising
- Uniforms, checks, and invoices.
22: Low temperature systems should have what?
- High pour point
- Low pour point
- High viscosity
- None of the above
23: What type refrigerant is NOT ozone depleting?
- CFC
- HCFC
- Halon
- HFC
24: _____ and its alloys are suitable for use with ammonia systems.
- Copper
- Aluminum
- Magnesium
- Zinc
25: Before replacing a seized compressor, the _______ should be determinded.
- type of refrigerant
- cause of seizure
- current draw
- designed head pressure