Automotive Air Conditioning and Repair 7-1 Goals of P2 in Automotive Air Conditioning Service Work n Pollution Prevention Goals –Minimize refrigerant vented to the atmosphere, and –Use effective alternatives to R-12.

Automotive Air Conditioning and Repair 7-2 (a) Minimize Refrigerant Venting n Prevent refrigerant loss during service. –Evacuate all refrigerant before maintenance or repair. –Shutoff valve on manifold hoses –Immediately evacuate leaking AC systems coming into the shop. –Establish a policy to encourage customers to repair rather than “top off”

Automotive Air Conditioning and Repair 7-2 (b) Minimize Refrigerant Venting –Avoid using products containing R-12 to find in-system leaks –Visually inspect the hoses, connections and condenser. –Use an electronic sniffer to detect the leaks. –When recharging AC systems: »Do not use small (12 ounce) disposable containers of refrigerant.

Automotive Air Conditioning and Repair 7-3 Storage of Refrigerants n Avoid leaking of stored refrigerant >> use only DOT or UL approved containers. n Label containers correctly. n Avoid cross contamination –Store different refrigerants separately. –Segregate contaminated refrigerants >> store in a specially labeled container.

Automotive Air Conditioning and Repair 7-4 (a) Alternative Refrigerants n Always check pertinent regulations and the vehicle manufacturer before using. n Many new refrigerants and blends are not compatible with the R-12 or R-134a. –Evacuation can contaminate refrigerant in the reclaimer. –Must be sent to a reclamation facility for separation and recycling.

Automotive Air Conditioning and Repair 7-4 (b) Alternative Refrigerants n A label under the hood should identify refrigerant type. n Equipment is available to identify R-12 or R-134a or unknown n Caution: Some alternatives contain liquefied petroleum (LP) gas. – Explosion risks!!

Automotive Air Conditioning and Repair 7-5 (a) Retrofitting n R-12 production has stopped. n Enough R-12 stockpiled to keep current systems operating for several years. –Cost of R-12 is predicted to increase as supplies diminish ! n Systems will need to be retrofitted to use alternative refrigerants such as R-134a or MP52.

Automotive Air Conditioning and Repair 7-5 (b) Retrofitting n New refrigerants have characteristics and compatibility's that must be addressed. »The lubricants used in R-12 (mineral oils) are not compatible n Should not be used in retrofitted system. n Some lubricants used with R-134a and MP52 are highly hygroscopic. »System O-rings may not be compatible with the replacement refrigerant.

Automotive Air Conditioning and Repair 7-5 (c) Retrofitting »Compressor shaft seals may also need to be replaced when retrofitting. –Always check with air conditioning manufacturers prior to retrofitting ! –Re-label retrofitted systems –Install proper fittings to prevent the accidental contamination of the system