Topics: All categories in the pool
1: The measurement of heat in a particular substance is
- enthalpy
- specific heat
- sensible heat
- latent heat
2: Capacity control on an absorption system is typically accomplished by varying the
- pressure setting on the system's rupture disc
- rate at which heat is supplied to the generator
- speed of the chilled water circulatory pump
- speed of the condenser water circulator pump
3: Which refrigerant replaced R-12?
- R-22
- R-407A
- R-410A
- R-134A
4: The ASHRAE Standard 34 requires what type of alarm for equipment rooms using HCFC-123?
- refrigerant sensing
- phosgene gas sening
- A group sensing
- CO Sensing
5: If a refrigerant leaving the condenser is 94F and the condensing temperature is 105F, the subcooling is
- 11F
- 9F
- 21F
- 29F
6: What will occur if the strong solution in an absorption chiller becomes too strong?
- The machine will cool excessively as the solution crystallizes.
- The machine will stop cooling and the solution will evaporate.
- The machine will stop cooling and solution will crystallize
- The machine will cool excessively as the solution evaporates
7: Megaohm meter's main function is
- to detect weak motor winding insulation of a refrigeration or air conditioning compressor by creating high DC voltages to the compressor
- to detect very high resistances to ground of refrigeration or air conditioning compressors
- to test very high value capacitors for large 3-phase refrigeration compressors and blower motors.
- Both a and b are correct
8: According to ASHRAE Standard-15 9.8 Positive Displacement Compressor Protection, the pressure-relief device discharge into
- the low-pressure side of the system
- the high side of the system
- the liquid receiver
- both a and c are correct
9: R-11 belongs to Group
- A-2
- A-1
- B-1
- B-3
10: If the compression ratio on a centrifugal compressor rises too high, the compressor will stop pumping and make a loud sound commonly referred to as a
- splurge
- surge
- merge
- purge
11: What is the minimum size of the discharge pipe?
- Same size as the outlet of the relief valve
- One pipe size larger that the inlet of the relief valve
- Depends on size of manifold
- All of the above
12: 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
13: The location of a thermal bulb of a TXV affects
- the amount of liquid in the condenser.
- the amount of liquid refrigerant in the evaporator
- subcooling
- the amount of liquid returning to the compressor
14: Pressure vessels shall be provided with ___________in accordance with Section VIII of the ASME Boiler & Pressure Vessel Code
- over pressure protection as well as a temperature protection device
- Pressure vessels need no type of protection as long as it is hydrostatically tested every three months
- over pressure protection
- over pressure protection and a rupture disc
15: Which of the following are considered inorganic refrigerants?
- R-717 and R-718
- 410A and R-407C
- R-500 and R-502
- None of the above
16: The first step in mechanical refrigeration is
- compression
- condensation
- expansion
- evaporation
17: Humidity can be sensed with
- human hair
- bimetal
- thermometer
- pressure bellows
18: Pressure vessels with an internal volume of 3 cubic feet or more
- shall use fusible plugs
- shall use pressure relief devices
- shall use pressure relief devices or fusible plugs
- do not need pressure relief protection
19: How many volts would you read on a 480V system phase to phase?
- 0
- 480
- 1/3 the voltage
- 277
20: 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
21: Low pressure chiller systems use what type of compressor?
- Centrifugal
- Scroll
- Reciprocating
- Screw
22: What refrigerant is an inorganic compound?
- R-132A
- Ammonia
- R-410A
- R-22
23: 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?
- 96
- 38
- 88
- 58
24: A premise where large numbers of people congregate and from which occupants can not quickly vacate the space is considered
- mixed occupancy
- institutional occupancy
- commercial occupancy
- public assembly occupancy
25: Heat transferred by conduction from one body to another is done via:
- gas
- liquid
- solid
- All of the above