Topics: All categories in the pool
1: The Department that certifies the transportation of refrigerant is the
- EPA
- DOT
- RSES
- EPO
2: Name a CFC refrigerant(s):
- R-11
- R-12
- R-123
- both a & b
3: When an electronic bridge is in balance the bridge output will be
- 1 volt
- 15 volts
- 0 volts
- .01 volts
4: The critical temperature of a refrigerant gas occurs when
- any increase in pressure will not liquefy the gas
- any decrease in pressure will cause condensation
- the gas is no longer saturated
- the gas returns to a liquid
5: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.
- 100%
- 80%
- 75%
- 90%
6: Control systems can be classified by
- source of power
- economy of operation
- tonnage of system
- safety
7: The ____ design is the maximum pressure for which a specific part of a refrigeration system is designed.
- low pressure
- design pressure
- critical pressure
- high pressure
8: On a pumpdown system, the liquid-line solenoid is controlled by the
- defrost timer
- thermostat
- low-ambient controller
- low pressure switch
9: Increasing superheat will do what to your frost line?
- Nothing
- Decrease
- Increasae
- Could either increase or decrease depending on the load conditions
10: Indirect systems using Group II refrigerants
- shall be used in refrigeration system less than 1,000 lbs
- shall be used for mechanical equipment only
- 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
11: If the spring is adjusted to increase the superheat, this new setting will
- allow more liquid into the evaporator
- have no effect on the frost line
- shorten the frost line
- lengthen the frost line
12: Sensible heat is the heat added to a substance to
- change its state
- cause evaporation
- freeze it
- raise its temperature
13: What type of voltage cause a potential relay to open?
- 24 volt supply from the thermostat
- 120 volt line voltage
- Pick-up voltage
- none of the above
14: Ammonia vaporization takes place at what temperature?
- -460F
- -32F
- -28F
- -110F
15: If the power element of an expansion valve should lose its charge the valve would
- overfeed the evaporator
- go closed
- go open
- underfeed the evaporator
16: Whoever owns/uses a refrigeration or air conditioning system covered by this code
- must notify the Department of Public Safety prior to starting the system
- shall be licensed by the Commonwealth of Massachusetts according to CMR 522
- shall make application for inspections to the Chief of Inspectors
- None of the above
17: Excessive head pressure is often caused by
- thermostat set too high
- air cooled condenser is plugged
- insufficient refrigerant
- leaking reed valve on the discharge side
18: A relief valve shall be located at least ___ above grade.
- 15'
- 25'
- 36'
- 10'
19: To determine the pump size needed for an open cooling tower system, the following must be known,
- GPM and balanced head and friction head
- GPM, pipe size, and equivalent head.
- GPM and unbalanced head and friction head
- GPM and friction head
20: What section of ASHRAE-15 governs pressure vessels?
- Section 9 ASHRAE-15 ASME VIII unfired
- Section 6 ASHRAE-34 ASME VIII unfired
- Section 7 ASHRAE-15 ASME VIII fired
- OSHA
21: When liquid receivers are used, the liquid refrigerant shall not exceed _______percent of the volume at 90F.
- 75%
- 80%
- 99%
- 90%
22: What type of fuses must be used on a HVAC system?
- TR Type, Duel Element, Time Delay
- Fast blow
- 10% lower than RLA
- none of the above
23: What measures gas pressure?
- Hydrometer
- Barometer
- Hygrometer
- Manometer
24: Insurance companies shall forward each inspection report of all refrigeration or A/C systems to the Chief of Inspections within
- 1 week
- 2 months
- 14 days
- 30 days
25: NH3 is
- R-508A
- ammonia
- lithium bromide
- R-718