Topics: ASHRAE/CMR
1: A positive displacement compressor is
- a compressor in which the increase in pressure is attained by changing the internal volume of the compression chamber
- is a reciprocating type compressor with 2 or more pistons
- where the compressor's suction pressure and the compressor;s discharge pressure is more than 50 PSI
- a compressor in which the increase in pressure is attained by changing the internal pressure of the compression chamber
2: 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
3: Walls and doors of a machinery room shall be at least _____ hour(s) fire rated.
- 5
- 1
- 2
- 3
4: How much clearance do you need around the perimeter of electrical panels?
- 24"
- 36"
- 18"
- 12"
5: R-717 is
- ammonia
- trichloromethane
- water
- carbon dioxide
6: Ammonia can come in contact with _______ ?
- Brass
- Aluminum
- Copper tubing
- Copper
7: What must be done to refrigerant pipes before being buried?
- Coated
- Certified
- Encased
- Leaked checked
8: What type of copper is not permitted on refrigeration systems?
- Type M
- Type N
- Type L
- Type K
9: Refrigerant restricted in 2004 but used for transition for decades:
- R-134A
- R-22
- R-123
- R-11
10: Pressure vessels with an internal volume of 10 cubic feet or more
- shall use pressure relief devices or fusible plugs
- shall use pressure relief devices
- shall use rupture discs or duel pressure relief valves
- shall use fusible plugs
11: Pressure vessels having design pressures of 15 psig or less shall have the strength to withstand at least ______times the design pressure.
- 2.5
- 3.0
- 2.0
- 5.5
12: High pressure controls should be set no higher than
- 10% of set point
- 80% of set point
- 25% of set point
- 90% of set point
13: When releasing a hydrogenated hydrocarbon refrigerant to the atmosphere, ample ventilation must be provided and
- gas masks must be worn
- no flames shall be permitted
- the owner shall be informed
- explosion precautions must be taken
14: What is the minimum height refrigeration piping should be placed against walls?
- Ceiling height
- 6'
- 72"
- 7.25'
15: Liquid shall not occupy more than ____ of the volume when the temperature of the refrigerant is 90F.
- 100%
- 80%
- 75%
- 90%
16: Can a R22 line set be reused for a 410A system and if it can be reused, what must be done to it?
- Flush with RX-11
- Flush with ammonia
- Flush with R-11
- Flush with R-718
17: 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
18: Who authorizes changes to the safety codes?
- Person in charge of the facility
- Person who pulled the permit
- Board of Boilers
- Contractor who last serviced the system.
19: How many different groups of refrigerants are there?
- 7
- 3
- 15
- 11
20: How many gallons of water per pound of ammonia do you need?
- 5
- 20
- 15
- 1
21: Institutional occupancy is
- a premise or that portion of a premise where large numbers of people congregate and from which occupants cannot quickly vacate the space.
- a premise or that portion of a premise from which, because they are disabled, debilitated, or confined, occupants cannot readily leave without the assistance of others.
- a premise or that portion of a premise where people transact business, receive personal service, or purchase food and other goods.
- None of the above
22: Where must a refrigeration contractor's license number be displayed?
- Truck, office, every job, and on all equipment
- Uniforms, checks, and invoices.
- Trucks, invoices, and advertising
- Trucks, license plates, and uniforms
23: What type of refrigerants are NOT flammable?
- CHC
- HFC
- HCFC
- All of the above
24: Fusible plugs shall not be used with pressure vessels of
- 3 cubic feet or more
- 15 cubic feet or more
- 3 cubic feet or less
- 15 square feet or less
25: A Low-Probability System
- is a system highly likely to leak form a failed connection or component of such system
- is such that a leak of refrigerant from a failed connection can not enter the occupied space
- is such that any leak will cause injury or death to anyone within a 100 square foot area
- is such that a leak of refrigerant from a failed connection will enter the occupied space