Topics: All categories in the pool
1: The high side float assembly meters refrigerant into the evaporator through the
- lower chamber of the low side
- upper chamber of the high side
- lower chamber of the high side
- upper chamber of the low side
2: RPM's of a centrifugal compressor are at approximately?
- 15,000
- 30,000
- 500
- 10,000
3: Ammonia can come in contact with _______ ?
- Copper tubing
- Brass
- Copper
- Aluminum
4: The purpose of a receiver is
- a vessel to store refrigerant outside the system
- to increase the capacity that the system can hold
- to use a a later date
- all of the above
5: An oil pressure safety switch should be set at
- 5 to 10 psi below low side pressure
- 5 to 10 psi above low side pressure
- 10-15 psi above low side pressure
- 10 to 15 psi below low side pressure
6: When an A/C system is excessively low on refrigerant
- it can become contaminated with water
- there can be nuisance trip outs
- the suction line may be too hot to touch
- All of the above
7: How many volts would you read on a 480V system phase to phase?
- 277
- 0
- 480
- 1/3 the voltage
8: The gauge thickness required on a CO2 tank construction is
- 1/8"
- 1/16"
- 5/16"
- 3/32"
9: On a TXV, the purpose of an external equalizer is to?
- compensate for a pressure drop across the evaporator coil
- balance the evaporator load
- allow a greater adjustment spam
- Increase the pressure on the top of the power head diaphragm
10: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
11: What type of relief valve is used on a CO2 system?
- fusible plug
- rupture disc
- glove disc
- gate valve
12: The certificate of inspection
- shall be posted and protected from dirt, water, and other elements
- shall be $20 and an additional fee of $1 for each tone above 20 tons
- shall be authorized by a notarized insurance company
- shall be posted on the compressor shell or electrical panel at the unit
13: A motor starter contains a thermal overload and a
- contactor
- transformer
- 3-way relay
- solenoid
14: Suction valve unloaders afford an effective means of
- evaporator control
- superheat control
- refrigerant control
- capacity control
15: Ammonia is under what safety classification?
- A3
- B2
- B1
- B3
16: No open flames are allowed in the machinery room unless?
- Approved by the installing contractor
- Never can be allowed
- Only when combustion air is provided from outside of the machinery room
- Approved by the authorized person
17: An electronic bridge circuit is basically a
- Wheatstone
- high voltage circuit
- 24 volt control circuit
- suspension
18: Halo-carbon refrigerants cannot be used with what material?
- Magnesium alloy
- Copper
- Stainless Steel
- Aluminum
19: What does an anemometer measure?
- voltage
- temperature
- velocity
- amperage
20: What happens after your initial inspection of a pressure vessel?
- 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.
- Inspector leaves a metal tag with a certification listed on it
- Notify the AHJ to let them know that the system been inspected
21: Horizontal piping should be run level.
- False
- Yes, if the condenser is located above the evaporator
- No, unless the supervisor on the job says so.
- True
22: "E" references ____ in the Ohm's law formula
- voltage
- amperage
- capacitance
- resistance
23: Indirect systems using Group II refrigerants
- shall be used for mechanical equipment only
- shall be used in refrigeration system in excess of 1,000 lbs
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
- shall be used in refrigeration system less than 1,000 lbs
24: Where are the three places that the discharge from an ammonia relief valve be piped?
- atmosphere, tank containing water, where the A.H.J. indicates
- underground, into drain, into mechanical room
- to chemical neutralizing tank only
- none of the above
25: Joints in refrigeration piping must be _____ before being covered?
- Pressurized
- Inspected
- Insulated
- Leak tested