Topics: All categories in the pool
1: A 3-cubic foot receiver must have what type of relief valve?
- fusible plug
- relief valve
- rupture device
- none of the above
2: Which winding have the most turns?
- Start
- they have equal amount of turns
- depends on the motor phase
- run
3: A single pole-double throw switch uses how many wires?(excluding the ground)
- 5
- 4
- 3
- 2
4: What pipe can not be used for refrigeration?
- L
- M
- N
- K
5: An azeotropic refrigerant is
- a mixture of two or more refrigerants that boil at about the same temperature minimizing temperature glide.
- a mixture of two or more refrigerants that boil at much different temperatures causing temperature glide
- a mixture of two or more refrigerants that boil at much different temperatures minimizing temperature glide
- none of the above
6: The discharge relief valve is located (9.4.6)
- between the compressor and the stop valve
- between the compressor and oil separator
- on top of the condensor
- between the compressor and reciever
7: 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
8: Large Mercantile occupancy is a premise or that portion of a premise where more than ____ persons congregate on levels above or below the street level to purchase personal merchandise.
- 100
- 350
- 250
- 400
9: If air is present in an absorption chilled water appliance, which of the following will most likely occur?
- Rust can form
- The Li-Br solution will become more concentrated
- The Li-Br solution will become more diluted
- System operating pressure will drop
10: Refrigerants shall be classified by
- toxicity and flammability
- maximum permissible quantities of each group
- requirements for commercial, industrial, and residential occupancies
- color codes
11: When must refrigeration system covered by the code be inspected?
- Annually and when installed
- Not required
- Upon installation
- Annually
12: What refrigerant doesn't have to be classifted?
- R-717
- R-711
- R-134a
- R-718
13: Low-side system leaks in a low-pressure chiller will often result in
- air being pulled into the system
- nitrogen leaking out of the system.
- system refrigerant leaking from the system
- water being pulled into the system
14: When should a relief valve start to function?
- Two times it's working pressure
- Before the purge station discharges
- 10 psi before it's set pressure
- At it's set pressure
15: A chilled water pump's suction gauge reads 10 psig. The discharge gauge reads 48 psig. What is the head in feet the pump is working against?
- 58
- 96
- 88
- 38
16: On an air cooled condenser, if the ambient air is 35F and dropping, what's its effect to the condensor?
- it would make the condenser more efficient
- it would cause the condenser to sweat
- it would have no effect on the condenser
- it would make the condenser less efficient
17: Atmospheric pressure is equal to
- 29.92" Hg
- 14.7 psia
- 14.7 psig
- both a & b
18: All serviceable components of a refrigeration system shall be provided with
- service manuals
- safe access
- manufactures instructions on start-up procedures
- name plates with markings referring to pressure and temperature in accordance with ASME Boiler and Pressure Vessel Code
19: Volts x amps equals
- Inductance
- Ohms Law
- Watts
- Impedance
20: Pressure vessels nameplate markings must be compliant with the
- ASHRAE 34 Standards
- CMR-588 & CMR-528
- ASME Boiler and Pressure Vessel Code
- All of the Above
21: When the compressor is below the condensor
- traps are not needed on this type of system
- traps are needed on the discharge line
- traps are needed on the oil return line
- traps are needed on the suction line
22: Refrigeration piping before being buried shall be
- leak tested
- encased in pipe duct
- pressure tested
- All of the above
23: Color is important in oil because
- it makes sight glasses easy to read
- can tell us something about the refining of oil
- allows you to see into crankcase
- it indicates the viscoisty.
24: Which of the following is NOT a positive displacement compressor?
- scroll
- screw
- centrifugal
- reciprocating
25: RPM's of a centrifugal compressor are at approximately?
- 500
- 10,000
- 15,000
- 30,000