Topics: All categories in the pool
1: 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
- 2.40 volts
- 2,400 volts
- 240 volts
- 24.0 volts
2: Where are the three places that the discharge from an ammonia relief valve be piped?
- To chemical neutralizing tank only
- Underground, into drain, into mechanical room
- Atmosphere, Tank containing water, where the AHJ indicates.
- None of the above.
3: Single compound Refrigerants are classified by what two criteria?
- Flammability and temperature range
- Weight and color
- Flammability and toxicity
- Temperature range and hazardousness
4: What type of relief valve is used on low pressure centrifugal compressor systems?
- Spring-loaded relief valve
- Rupture disc
- Purge relief
- None of the above
5: Horizontal piping should be run level.
- No, unless the supervisor on the job says so.
- False
- Yes, if the condenser is located above the evaporator
- True
6: How many square inches per square foot?
- 24
- 98
- 144
- 64
7: How many refrigerant classifications are there for toxicity?
- 3
- 5
- 1
- 2
8: An oil pressure safety switch should be set at
- 5 to 10 psi above low side pressure
- 10-15 psi above low side pressure
- 5 to 10 psi below low side pressure
- 10 to 15 psi below low side pressure
9: Lithium-bromide, Li-Br, is best characterized as a
- sand
- sugar
- salt
- soil
10: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Moisture indicator
- Foot valve
- Muffler
- Stop valve
11: Which of the following types of oils are hygroscopic?
- polyolester (POE)
- polyalkylene glycol (PAG)
- naphthene mineral
- both a and b
12: How many CFMs are required per square foot of commercial office occupied space
- .5 CFM
- 5 CFM
- 15 CFM
- 20 CFM
13: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.
- high pressure
- design pressure
- critical pressure
- low pressure
14: A 3-cubic foot receiver must have what type of relief valve?
- fusible plug
- relief valve
- rupture device
- none of the above
15: Where a refrigeration or air conditioning system is installed,
- the form or certificate shall be authorized by the Department of Public Safety
- A field inspection shall be made before it is put into service
- The company who installed the system must notify the fire department in the jurisdiction where installed
- it shall not be operated below prescribed pressuers
16: Class T machine room
- shall have refrigerant leak detecting systems installed inside and outside the room
- shall have remote controls to stop the action of the refrigerant compressor
- has no flame producing apparatus permanently installed
- shall include closets used for setting equipment
17: On a TXV, the purpose of an external equalizer is to?
- compensate for a pressure drop across the evaporator coil
- Increase the pressure on the top of the power head diaphragm
- allow a greater adjustment spam
- balance the evaporator load
18: Doors communicating with outside from a mechanical room must be?
- Self-closing, approved, fire door
- Self-closing, wooden, fire door
- Self-closing, aligned, fire door
- Steel, approved, weather-stripped
19: System design pressures must take into consideration, not only, pressures found during normal operation but also what?
- When it's cold out
- When there is a malfunction on the high side
- When its warm out
- All of the above
20: If an oil’s floc point is too high, which of the following could occur?
- low head pressure
- high suction pressure
- plugged expansion valve
- compressor burn out
21: Color is important in oil because
- it makes sight glasses easy to read
- allows you to see into crankcase
- can tell us something about the refining of oil
- it indicates the viscoisty.
22: What is the minimum height refrigeration piping should be placed against walls?
- 6'
- 7.25'
- 72"
- Ceiling height
23: What is potential measured in?
- Amps
- Ohms
- Volts
- Henrys
24: When an electronic bridge is in balance the bridge output will be
- 1 volt
- .01 volts
- 0 volts
- 15 volts
25: _____ and its alloys are suitable for use with ammonia systems.
- Copper
- Aluminum
- Magnesium
- Zinc