Topics: All categories in the pool
1: Give an example of a secondary coolant?
- R-410A
- R-718
- R-717
- R-12
2: An air conditioning system rated for 36,000 BTU's is equivalent to
- three tons of cooling
- two tons of cooling
- one ton of cooling
- 12,000 tons of cooling
3: Methyl Chloride is a halogenated refrigerant and should not come in contact with
- aluminum
- zinc
- magnesium
- all of the above
4: Lithium-bromide, Li-Br, is best characterized as a
- salt
- sand
- soil
- sugar
5: A normally operating R-410A system with a condensing temperature of 110F will have a high side pressure of around ______ psig
- 125 psig
- 327 psig
- 365 psig
- 255 psig
6: What should not (and can not) be located between a pressure imposing device and a pressure-limiting device?
- Stop valve
- Muffler
- Moisture indicator
- Foot valve
7: A tachometer is an instrument used to measure
- RPM
- static pressure
- speed
- air velocity
8: Joints in piping for refrigeration containing parts must withstand temperatures of ___?
- 800F
- 600F
- 1000F
- 700F
9: R-11 belongs to Group
- B-3
- B-1
- A-1
- A-2
10: Start to Run windings will have what resistance?
- All will be at equal values
- The least resistance value
- Somewhere between the actual start winding and run winding resistance value
- The most resistance value
11: What type refrigerant is NOT ozone depleting?
- CFC
- Halon
- HCFC
- HFC
12: The reversing valve is commonly used
- when the code requires a check valve
- on commercial system that involve two different temperatures
- on multiple compressor systems
- on all heat pumps
13: Which of the following is an example of an azeotropic refrigerant?
- R-500
- R-404A
- R-410A
- R-134A
14: When a pressure gauge is permanently installed on a system, it must be ___ times the design pressure of the system.
- 1.5
- 1
- 1.2
- 2.2
15: Which creates more of a heat load?
- 30% RH
- 70% RH
- 50% RH
- 90% RH
16: The Board of Boilers adopts by reference
- MSCA Code
- Montreal Protocol Safety Code
- the MACS Pressure Vessel Code of Massachusetts
- the 1997 ANSI/ASHRAE Safety Code
17: Laten heat is associated with a change in state of a refrigerant but not temperature
- True
- False
18: The best way to detect ammonia in brine is
- potassium of line
- carbonation of soda
- CO2 gas
- nessler regaent
19: R-22 falls under which safety classification?
- B-1
- B-2
- A-2
- A-1
20: When can recovered refrigerants be reused?
- They can't
- Only when used in original owner's equipment
- Only if used in 30 days of recovery
- None of the above
21: What is the state of the refrigerant leaving the evaporator?
- a high temperature subcooled liquid
- low temperature superheated vapor
- a low temperature subcooled liquid
- a high temperature superheated vapor
22: Which of the following is NOT a positive displacement compressor?
- reciprocating
- scroll
- centrifugal
- screw
23: Machinery rooms shall be vented to _____________ and utilizing mechanical ventilation.
- the return air ducted system
- the mechanical room housing the refrigeration system
- Machinery rooms need not be vented
- the outdoors
24: R-718 is rated unlimited for refrigeration quantity contained in a system. Why?
- Because it's a non-flammable refrigerant
- Because it's water
- Because it's cheap
- R-718 is not rated unlimited because it's a dangerous refrigerant
25: The instrument used to measure the specific gravity of absorption chiller solutions is the
- Psychrometer
- hydrometer
- anemometer
- refractometer