Guide for Retrofitting R-134a

The term " modernization describes the special procedures required for the conversion of R-12 system to use an alternative refrigerant. This section describes some facts about the aftermarket functions and procedures for modernization Air conditioning and refrigeration systems for R-134a. As is known, R-134a is selected from around the world to be a long-term replacement of R-12 in refrigeration and air conditioning systems.

Producers (also known as original equipment manufacturers) have been developed upgrade kits or guidelines for some of the models. These procedures were designed to provide the best level of performance with the new R-134a systems. While these kits and guidelines will provide the greatest assurance that a comparable system performance will be achieved, the cost of these procedures will in many cases be relatively high. Procedures necessary for the lowest cost of modernization are simple and do not require major changes in the components. As a rule, the process calls for the removal of the old refrigerant and installation of accessories and a new label, and the addition or polyalkylene glycol (PAG) or polyester (POE or ether) in the lubricant, as well as R-134a refrigerant.

According to the rules of the EPA, 2009), the use of any the alternative refrigerant for replacement of R-12 requires, as a minimum,

• unique service fittings to be used in order to minimize the risk of cross-contamination, or the cooling system or service center recycling equipment;
• new refrigerant be identified by a unique color for the identification of the refrigerant in the system;
• all R-12 to be completely removed from the system before filling the system with the alternative refrigerant;
• in order to prevent the release of refrigerant to the atmosphere of the high-pressure compressor shut-off switch be installed on any system equipped with a pressure-relief device;
• separate equipment for recovery of R-12 from the system.