HVAC System Evacuation and Refrigerant Safety

PRACTICE TEST Question To obtain an accurate vacuum readings during system evacuation, the system vacuum gauge should be located: When moisture exists in an operating system, which of the following is the most likely occur? Answer as far from the vacuum pump as possible Acid will form. Refrigerant vapors or mist should not be inhaled because: 1)The size of the equipment being evacuated 2)The ambient temperature 3)The amount of moisture in the system Remove water and water vapor dehydration equal to or larger than vacuum pump inlet connection the system isolated and the vacuum pump off they may cause heart irregularities and/or unconsciousness A refillable refrigerant cylinder must never be filled to more than _____ of its capacity by weight: 80% What factor(s) affects the speed of evacuation? A system is dehydrated to: The evacuation of a system is a method of: When evacuating a sytsem, the hoses should be: Measuring the system's final vacuum is always with: Refrigerant cylinders should always be: Which safety precautions(s) should always be followed: 1) free of rust and damage 2) color coded to indicate the contents 3) secure 1) Never apply an open flame to a refrigerant cylinder 2) Never cut or weld any refrigerant line when refrigerant is in the line 3) Never use oxygen to purge lines or to pressurize a system 1) a mechanical float switch 2) an electronic shutoff device 3) weight When using recovery unit, the fill level of the recovery tank can be controlled by: Whenever dry nitrogen from a portable cylinder is connected There is a relief valve in the downstream line from to a system, what item is of most importance in consideration the pressure regulator of safety? A measure of the ability of CFCs' and HCFCs' to Ozone depletion potential, or "ODP" is: destroy ozone An example of an HCFC refrigerant is: R-22 When transporting cylinders containing used refrigerant, the attach DOT classification tags DOT requires that you: a refrigerant cylinder which is being returned for It is necessary to place a refrigerant label on: reclaiming lose their EPA certification 2) be fined 3) be Refrigeration technicians who violate the Clean Air Act can: 1) required to appear in Federal court The type of oil that is most commonly used in stationary ester oil refrigeration applications with HFC-134a refrigerant is: In a vapor compression refrigeration system, cooling occurs refrigerant liquid turns to a vapor when: _________refers to the process of cleaning refrigerant by oil separation and single or multiple passes through filter-driers, recycling which reduce moisture and acidity? According to the EPA, a _______ leak detection methods is considered to be the most effective for locating the general Electronic or Ultrasonic tester area of a small leak When a system will not hold a vacuum after it has been the system may be leaking evacuated, then: We dealing with small systems, how many different only one refrigerants may be recovered into the same cylinder? If the EPA regulations should change after a technician it is the technician's responsibility to comply with becomes certified: any future changes in the law The EPA Section 608 certification must be renewed every: The EPA certification has no expiration date You are changing the compressor of a system containing 12 pounds R-410A. Your recycling equipment was manufactured AFTER November 15, 1993. You must reach a vacuum of at leas ____ inches of vacuum with the recovery or recycling machine Recovery or recycling equipment which was manufactured after November 15, 1993 and is used to recover refrigerant from small appliances prior to disposal of the small appliances must be used to: Technicians with a Type I small appliance certification are certified to recover refrigerant during the maintenance, service or repair of: A Very-High-Pressure appliance is one that uses a refrigerant with a liquid phase saturation pressure above 305 psia at 104F. This definition includes but is not limited to appliances using which of the refrigerants listed below: The sale of refrigerant is: For which of the following refrigeration systems/appliances would it be permissible to use a passive recovery device for refrigerant recovery? EPA regulations require the capture of at least 80% of the refrigerant from a small appliance with a non-operating compressor if the technician is using: When ever nitrogen is used to pressurize or blow debris out of the system: A recovery cylinder which is half full of recovered R-22 at normal room temperature (about 75F), in the absence of noncondensables, will be pressurized to: Small amounts of refrigerant have no odor, therefore if a pungent odor is detected during a system recovery and/or repair: 0 1) recover 80% of the refrigerant in an appliance's compressor is inoperative. 2) recover 90% of the refrigerant in an appliance if the appliance's compressor is operational packaged terminal air conditioners ("PTACs) with 5 pounds or less of refrigerant 1) R-410A 2) R-13 3) R-503 restricted to technicians who are EPA certified in refrigerant recovery a domestic refrigerator 1) a system-dependent (passive) recovery unit 2) a self-contained (active) recovery unit only nitrogen vapor should be used 130 psig a compressor burn-out has likely occurred If a reclamation processing plant is given a recovery tank containing a mixture of refrigerants, they can: 1) refuse to process the refrigerant and return it 2) agree to destroy the refrigerant, but typically a substantial fee is charged for the destruction When ever nitrogen is used to pressurize or blow debris out of the system, the nitrogen: can be vented must be recovered into its own recovery vessel (or a recovery cylinder that already contains some R500) A standard vacuum pump designed specifically for evacuation be only used as a recovery device in combination and dehydration can: with a non-pressurized container A recovery cylinder which is half full of recovered R-500 at normal room temperature (about 75F), in the absence of non- 95 psig condensables, will be pressurized to: After installing and opening a piercing access valve, if the system pressure is ____ do not begin the recovery procedure 0 psig When using a passive-dependent recovery process, you should access both the high and low side of the system for the the system's compressor does not run refrigerant recovery if __________. A refrigerant that can be used as a direct service "drop-in" None of the above (R-410A, R134a, R-141b) substitute for R-22 in a small appliance is: When transporting refrigerants, DOT (Department of Transportation) Regulation number 49 CFR requires ____________ to be recorded on the shipping papers for hazard number of cylinders of each gas class 2.2, Nonflammable compressed Gases? If a large leak of refrigeration occurs in an enclosed area and no self-contained breathing apparatus is available, then the vacate and ventilate the spill area technician should: Large spills of refrigerants can cause suffocation because: they are heavier than air and displace oxygen When using any equipment or servicing any system that has 1) inspect the schraeder valve core for bends and schraeder valves, it is "critical" to: breakage 2) replace any damaged schraeder valve When R-500 is recovered from an appliance, it: core to prevent leakage 3) can the schraeder ports to prevent accidental depression of the valve core If R-12 or R-22 are exposed to high temperature, (from open flames or glowing hot metal surfaces for example), these refrigerant can decompose to form: hydrochloric and hydrofluoric acids