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Detailed information on the stratospheric ozone layer, the molecules that deplete it, the environmental and health impacts of ozone depletion, and the regulations surrounding the use and disposal of refrigerants that contain ozone-depleting substances. It covers topics such as the composition of cfcs and hcfcs, the ozone depletion potential of different refrigerants, the epa regulations on venting and disposal of refrigerants, the certification requirements for technicians, and the proper recovery and recycling procedures for different types of refrigeration and air conditioning equipment. The document also discusses the international agreements that have been put in place to regulate the production and use of ozone-depleting substances, as well as the transition to alternative refrigerants that are more environmentally friendly.
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The layer of the Stratosphere that protects us from excessive Ultra Violet radiation is comprised of; - Solution ozone The molecule found in CFC's and HCFC's that depletes ozone is: - Solution chlorine Crop loss, eye disease, and skin cancer have been attributed to; - Solution depletion of stratospheric ozone How many chlorine atoms does it take to destroy 1,000,000 (one million) ozone molecules? - Solution 10 The chlorine in CFC's will; - Solution not dissolve in water HCFC's contain - Solution hydrogen, chlorine, fluorine, carbon Which of the following has the highest Ozone Depletion Potential? - Solution cfcs Technicians have been required to be certified to service, maintain, or dispose of appliances containing regulated refrigerants since. - Solution november 14 , 1994 It has been a violation of EPA Section 608 regulations to vent CFC's or HCFC's since; - Solution july 1, 1992 It has been a violation of EPA Section 608 regulations to vent HFC's since - Solution november 15, 1995
Recover any remaining refrigerant and then render the cylinder useless, then recycle the metal is the proper disposal method for; - Solution disposable cylinders Which international agreement (Treaty) regulated the production and use of CFCs, HCFC's, halons, methyl chloroform and carbon tetrachloride? - Solution montreal protocal Clean refrigerant for reuse by separating the oil from the refrigerant and removing moisture from the refrigerant by passing it through one or more filter driers, is the definition of; - Solution recycle To process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis defines; - Solution reclaiming HFC's ________; - Solution will not damage stratospheric ozone When chlorine monoxide is found in the stratosphere, it indicates that; - Solution the ozone layer is being depleted Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) - Solution are odp substances The two types of recovery systems are - Solution system dependent and self contained When a system is in full vacuum ____________ - Solution never energize the compressor The evaporator ___________________ - Solution changes a low pressure liquid to a low pressure vapor The condenser _______________________________________ - Solution changes a high pressure vapor to a high pressure liquid The metering device ______________________________ - Solution changes a high pressure liquid to a low liquid The compressor ____________________________________ - Solution changes a low pressure vapor to a high pressure vapor
What is defined as a non-condensible? - Solution air When using a system-dependent recovery system on an appliance that has an operating compressor, the technician should; - Solution run the compressor and recover from the high side of the system When using a system-dependent recovery system on an appliance that has a non-operating compressor, the technician should; - Solution place access fittings on both the low and high sides of the system System-dependant devices may only be used on appliances containing; - Solution 15 pounds of refrigerant or less Small appliances are equipped with a straight piece of tubing (process stub) used to; - Solution install a piercing type access valve fitting If a strong odor is detected while performing the recovery process, - Solution a compressor burn out has likely occured After the refrigerant has been recovered, which of the following can be used to flush the system? - Solution nitrogen When filling a charging cylinder with a regulated refrigerant; - Solution the refrigerant vapor that is vented off the top of the cylinder must be recovered If after installing a fitting for the purpose of recovering the appliances refrigerant, you find that the system pressure is 0 psig; - Solution recovery is not required Applying heat with a heat gun to the compressor; - Solution can help vaporize any trapped liquid refrigerant during recovery Refrigerators in the 1950's and earlier may have used what refrigerants (recovery is not required)? - Solution methyl formate, methyl chloride, or sulfer dioxide Small appliances in recreational vehicles may use refrigerants such as Ammonia, Hydrogen, or water, and therefore; - Solution the refrigerant should not be recovered
Recovery equipment manufactured before November 15, 1993 must be capable of recovering. - Solution 80 percent of the refrigerant or achieving 4 inches of vacuum When pressurizing a system with nitrogen you should; - Solution charge through a pressure regulator, place a relief valve in the downstream line from the pressure regulator After recovering refrigerant, the Nitrogen used to flush the system may be: - Solution legally vented Industrial process and refrigeration units with a 50 pound charge or more with an annualized leak rate of _____ or more must have leaks repaired. - Solution 35 % Unless plans are made to replace a system exceeding the maximum leak, repairs must be made in; - Solution 30 days Refrigerants CFC R-12, HCFC R-22, and HFC 134a are all classified as; - Solution type A- All Refrigeration & HVAC systems are protected by a; - Solution pressure relief valve A refrigerant sensor which will sound an alarm and automatically start a ventilation system in occupied equipment rooms fall under; - Solution ASHRAE Standard 15 Non-condensables will cause; - Solution high discharge pressure A crankcase heater is often used to prevent refrigerant from migrating to the oil during periods of: - Solution low ambient temperature EPA regulations state that maintenance, service or repair involving the removal of the following component is a "major repair" - Solution compressor What refrigerant can be used as a trace gas when checking for leaks? - Solution R-
EPA regulations require that all Commercial and Industrial Process Refrigeration containing more than 50lbs. of refrigerant MUST be repaired when the annual leak rate exceeds; - Solution 35 % Proper recovery techniques begin with the use of appropriate recovery equipment that has been certified by; - Solution EPA approved laboratory What happens to a refrigerant that is above the saturation temperature? - Solution it remains in a vapor state Which of the following refrigerant is considered high or very high pressure refrigerant? - Solution HFC- 134 a Air conditioning system short cycling is normally caused by; - Solution the system being oversized for the home What type of equipment can be worked on with Type III certification? - Solution low pressure The most efficient method of leak checking a charged low-pressure refrigeration unit is to - Solution pressurize the system by the use of controlled hot water or heater blankets When pressurizing a system, do not exceed - Solution 10 psig After reaching the required vacuum on an appliance when servicing, moisture is indicated by; - Solution multiple rises in pressure over a period of time with increase of pauses between rises EPA required evacuation levels for recovery or recycling equipment manufactured or imported before Nov. 15, 1993 is - Solution 25 inches of HG EPA required evacuation levels for recovery or recycling equipment manufactured or imported on or after Nov. 15, 1993 is - Solution 25 mm HG absolute What can be used to pressurize a chiller system before opening the system for a non-major repair? - Solution controlled hot water
Refrigerant recovery from a system using R-11 or R-123 starts with - Solution liquid removal and is followed by vapor recovery If a strong odor is detected during the recovery process, - Solution a compressor burn out may have occurred When installing more than one pressure relief valves must be installed; - Solution in parallel The owner must keep records of refrigerant added during service and maintenance on equipment; - Solution with charges of 50 lbs or greater After all the liquid has been removed from an average 350 ton approximately how much vapor refrigerant remains in the system - Solution 100 lbs When charging a system with a low pressure refrigerant should be introduced as a vapor to raise saturation temperature to a minim of; - Solution 36 degrees Where is the purge unit located in a low-pressure system? - Solution the top of the condenser In a chiller air and other noncondensables collect; - Solution at the top section of the condenser A rupture disk for low pressure chiller will rupture at; - Solution 15 psig The Standard for machine room safety is; - Solution ASHRAE - 15 Who establishes the refrigerant safety group standard - Solution ASHRAE A low pressure chiller used for comfort cooling must be repaired if it has an annual leak rate of ____ of the total charge. - Solution 15 percent ASHRAE 34 Standard Safety classifies R-134a as; - Solution A Because a low-pressure system operates below atmospheric pressure (in a vacuum), - Solution leaks in the gaskets or fittings will cause air and moisture to enter the system