Topics: All categories in the pool
1: When can 50/50 solder be used?
- in the low side
- in the high side
- liquid and suction lines
- none of the above.
2: The leaving chilled water set point for comfort cooling is typically?
- 38
- 60
- 45
- 66
3: What is the purpose of a surge capacitor on a contactor?
- to provide smoother start/stops
- to keep the contactor pulled in
- to balance the sine waves
- to protect low voltage equipment
4: 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
- 24.0 volts
- 240 volts
- 2.40 volts
- 2,400 volts
5: In a system designed for sub-zero ambient temperatures, what must be added?
- Nitrogen
- Low-ambient kit
- Infrared dye for leak identification
- Booster compressor
6: The total amount of refrigerant stored in a machinery room in all containers not provided with relief valves shall not exceed
- 55 lbs
- 660 lbs
- 550 lbs
- 330 lbs.
7: B3 refrigerants are considered
- toxic but non-flammable
- non-toxic but flammable
- non-toxic but non-flammable
- toxic and highly flammable
8: The pressure relief device of a positive displacement compressor shall discharge in the ______________or in accordance with 9.7.8
- the vapor side of the system
- low side of the system
- the liquid side of the system
- high side of the system
9: A chiller entering and leaving temperature difference is?
- 50 degrees F
- 10 degrees F
- 20 degrees F
- 5 degrees F
10: Defined process piping by code CMR (528)
- Any piping that conveys a solid, liquid or gas that is not part of the plumbing or fire protection system
- Any piping in an industrial space
- Any piping in an industrial or commercial space
- All of the above
11: Which oil is hydoscopic?
- mineral
- polyolester
- SW30
- animal
12: Class 3 refrigerants are
- non-toxic
- non-flammable
- highly flammable
- toxic
13: A water regulating valve opens when
- the head pressure rises
- when the power is on
- the compressor is on
- when the power is on there is an overcharge of refrigerant
14: Liquid refrigerant R-22 enters an evaporator at 50.2 psig, 20F and leaves 37F, its pressure as it leaves will be
- 70.8 psig
- 66.1 psig
- 43.3 psig
- 50.2 psig
15: 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
16: Refrigeration piping before being buried shall be
- leak tested
- encased in pipe duct
- pressure tested
- All of the above
17: When the compressor is below the condensor
- traps are needed on the suction line
- traps are needed on the oil return line
- traps are needed on the discharge line
- traps are not needed on this type of system
18: Where a refrigeration or air conditioning system is installed,
- it shall not be operated below prescribed pressuers
- A field inspection shall be made before it is put into service
- the form or certificate shall be authorized by the Department of Public Safety
- The company who installed the system must notify the fire department in the jurisdiction where installed
19: Class T machine room
- has no flame producing apparatus permanently installed
- shall have remote controls to stop the action of the refrigerant compressor
- shall include closets used for setting equipment
- shall have refrigerant leak detecting systems installed inside and outside the room
20: How are a compressor and condenser fan wired?
- series-parallel
- series
- parallel-series
- parallel
21: Each machinery room shall contain
- a toxicity detector where the presence of ammonia or lithium bromide from a leak will concentrate
- high and low pressure controls
- a refrigerant detector located in an area where the refrigerant from a leak will concentrate
- smoke and fire alarms as well as three means of egress and that egress must meet 528 CMR ventilation requirements
22: Which of the following controllers would you expect to be most sensitive to temperature changes?
- line voltage t-stat
- aquastat
- immersion controller
- low voltage t-stat
23: A room having machinery but no flame producing apparatus permanently installed and operated is considered a
- Class A machinery room
- Class M machinery room
- Class B machinery room
- Class T machinery room
24: What refrigerant were phased out in 2004?
- R-22
- R-11
- R-134a
- R-12
25: 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