Topics: All categories in the pool
1: A VRF system is a direct system
- true
- false
2: A class A3 refrigerant is considered
- non-toxic and non-flammable
- non-toxic but highly flammable
- toxic and non-flammable
- toxic and somewhat flammable
3: When using nitrogen for brazing, the pressure should be:
- 125 psig
- Slightly below atmospheric
- Very low
- 50-100 psig
4: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
5: How are safety controls wired in a circuit?
- Series/parallel
- Parallel
- Series
- Either series or parallel
6: Usually dry bulb temperature is
- not important and shall be ignored
- same as wet bulb temperature
- lower than dry bulb temperature
- higher than wet bulb temperature
7: When a refrigerating machinery room is used, the emergency procedures shall be posted
- outside the room, immediately adjacent to each door
- on a conspicuous card located near the evaporator
- on a conspicuous card located near the compressor
- inside the room, immediately adjacent to each door
8: "I" represents ____ in the Ohm's law formula.
- amperage
- capacitance
- voltage.
- resistance
9: Capacity control on a centrifugal compressor is accomplished by the
- pre-rotational guide vanes
- slide vanes
- check valves
- post-rotational guide vanes
10: The freezing point of water at sea level is?
- 32F
- 32C
- -10C
- 0F
11: Absolute pressure is
- Gauge Pressure
- Atmospheric Pressure
- Gauge + Atmospheric Pressure + Pi
- none of the above
12: What are the three components of a transformer?
- Contacts, secondary coil, and core
- Primary core, secondary coil, and high and low voltage connectors.
- Primary coil, secondary coil, and copper contacts
- Primary coil, secondary coil, and core
13: Single compound Refrigerants are classified by what two criteria?
- Flammability and toxicity
- Weight and color
- Temperature range and hazardousness
- Flammability and temperature range
14: What type of copper is not permitted on refrigeration systems?
- Type M
- Type L
- Type N
- Type K
15: 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
16: What happens after your initial inspection of a pressure vessel?
- Inspector leaves a metal tag with a certification listed on it
- Notify the AHJ to let them know that the system been inspected
- Notify the Fire Marshal that the system has been inspected and approved
- There is a temporary shut-down until a final inspection can be performed.
17: The normal operating evaporator temperature of R-410A for air conditioning is typically
- 32F
- 158F
- 45F
- 155F
18: What type of oil is used in R-410A systems?
- mineral oil
- polyolester (POE)
- polyalkylene glycol (PAG)
- naphthene
19: A class B1 refrigerant is considered
- toxic and somewhat flammable
- non-toxic and non-flammable
- toxic but non-flammable
- non-toxic but highly flammable
20: A total of all group A-2,B-2, A-3, and B-3 refrigerants shall not exceed ____ lb in the occupied areas and machinery rooms of institutional occupancies.
- 100
- 50
- 350
- 550
21: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
- 1000F
- 600F
- 700F
- 800F
22: A water regulating valve opens when
- the head pressure rises
- the compressor is on
- when the power is on
- when the power is on there is an overcharge of refrigerant
23: What would be the classification of a prison?
- Industrial
- Institutional
- Large mercantile
- Place of assembly
24: R22 and 410A operate at the same range of condensing and evaporating temperatures
- true
- false
25: What kind of system uses two different refrigerants in separate systems dependent on each other?
- Cascade
- Simple
- R-414B
- Low pressure