Topics: All categories in the pool
1: If a liquid receiver is designed to receive the refrigerant charge during a pumpdown procedure, it shall have the capacity to
- hold up to 110% of the pumpdown charge
- Pumpdown procedures are not allowed with systems containing liquid recievers
- receive the pumpdown charge
- release the charge when the pressure exceeds 310 psig or higher
2: How much clearance do you need around the perimeter of electrical panels?
- 12"
- 36"
- 24"
- 18"
3: What is the temperature that a liquid and a vapor can exist in equilibrium called?
- Saturated temperature
- Critical temperature
- Dry bulb temperature
- Wet bulb temperature
4: What type of copper is not permitted on refrigeration systems?
- Type N
- Type L
- Type M
- Type K
5: In a system designed for sub-zero ambient temperatures, what must be added?
- Low-ambient kit
- Infrared dye for leak identification
- Nitrogen
- Booster compressor
6: Floc point is
- the lowest temperature at which dissolved waxes and solids begin to separate in a system
- the highest temperature at which dissolved waxes and solids begin to separate in a system
- the lowest temperature at which dissolved waxes and solids begin to solidify in a system
- the highest temperature at which dissolved waxes and solids begin to solidify in a system
7: The solution that is pumped into the concentrator in an absorption chiller is referred to as the
- weak solution
- absorbed solution
- strong solution
- concentrated solution
8: Pi equals approximately
- 3.14
- 3.41
- 12,000
- 746
9: Low ambient controls are used when
- economizers are used
- when systems run all year round
- on air conditioning systems only
- always
10: Name an HCFC refrigerant(s):
- R-22
- R-123
- R-11
- both a & b
11: Which of the following is an inorganic refrigerant?
- R-22
- Ammonia
- Chlorofluorocarbons
- All of the above
12: R-12 is
- dichloromethane
- dichlorofluoromethane
- dichlorodifluoromethane
- trichlorofluoromethane
13: The generator shell contains the
- evaporator and the absorber
- condenser and the absorber
- condenser, the evaporator, and the generator
- condenser and the generator
14: If a low-pressure chiller has a low-side leak, which of the following will most likely result?
- Low suction pressure and low discharge pressure
- High head pressure and low suction pressure
- Low head pressure and high suction pressure
- High suction pressure and high discharge pressure.
15: What's the purpose of a megohmmeter?
- To measure low to very low resistance values
- To alternate the current in a DC circuit in order to calculate the total impedance of a circuit
- To measure very high resistances
- None of the above
16: What should never be used in pressure testing refrigeration systems?
- Oxygen
- Compressed air
- Nitrogen
- Both a and b
17: Refrigerant is metered into the evaporator on a large centrifugal chiller thru the
- low side of the system
- high side float assembly
- cap tube
- none of the above
18: Indirect systems using Group II refrigerants
- shall be used in refrigeration system less than 1,000 lbs
- shall have all refrigerant containing parts except piping, installed in a Class T machine room
- shall be used in refrigeration system in excess of 1,000 lbs
- shall be used for mechanical equipment only
19: How many different groups of refrigerants are there?
- 7
- 11
- 3
- 15
20: What do you need to do when you install a new system?
- Document the superheat and subcooling reading
- Have it inspected
- Insulate the suction line before you take a superheat reading
- Add refrigerant
21: Most CFC's are
- inert
- toxic
- inert but toxic
- flammable
22: Where can 50/50 solder be used on?
- suction line
- liquid line
- discharge line
- none of the above
23: If the suction pressure is low and the evaporator temperature high, the cause will be a?
- compressor suction valve stuck open
- starved evaporator
- too small evaporator
- overcharged
24: Electricity involves the movement of electrons in atoms
- True
- False
25: According to the 522 CMR Board of Boilers, refrigerant detectors, alarms, and the refrigeration mechanical room ventilating systems shall be tested
- regularly
- quarterly
- bi-annually
- annually