HCFC-22 is a high capacity, efficient refrigerant employed in a significant number of air conditioning systems. The majority of these systems utilize mineral oil lubricants. Due to the phase-out of HCFCs, facility owners are considering retrofitting their mechanical systems to alternative refrigerant blends. The selection of a retrofit fluid depends, in part, upon retrofit objectives that may include factors such as efficiency, first cost, global warming potential and capacity. By following equipment manufacturer’s recommendations and Honeywell’s guidelines outlined in this publication, service technicians can readily retrofit many existing air conditioning systems Genetron 422D.
Genetron 422D is a “near drop-in” replacement. Genetron 422D is an HFC-based refrigerant that normally utilizes synthetic lubricants. The mass flow differences as well as the slightly different operating pressures should be evaluated. Check with the compressor manufacturer to determine if the existing lubricant is acceptable. The retrofit procedures have been developed by Honeywell to address these issues and to help technicians perform successful retrofits of HCFC-22 systems utilizing positive-displacement (reciprocating, rotary and scroll) compressors.
Safety Tips
1. Never mix refrigerants in a refrigeration system or recovery cylinder. Any refrigerant mixing creates a non-reclaimable mixture that will cost you or your customer more money in disposal fees.
2. Never leak-test a system using air, oxygen or other oxidizing materials. When combined with HFCs and HFC/Hydrocarbon Blends under pressure, these mixtures can become combustible.
3. Always read the label and Material Safety Data Sheet (MSDS) before working with the refrigerant(s).
4. Never “top-off” a system with a refrigerant other than what is already in that system. If you aren’t sure what’s in a system, either recover the full charge or have the refrigerant tested.
5. Always make sure systems you work on are properly labeled with the refrigerant and oil when you leave.
6. Do not store refrigerant cylinders in direct sunlight or in areas where temperatures could exceed 125° F or 51.7° C.
7. Keep smaller cylinders from becoming a rolling hazard by keeping them in their cartons while storing or transporting them.
8. Always recover the contents of non-refillable refrigerant cylinders to 0 psig or less before disposing of them. Whenever possible, recycle non-refillable cylinders at a local metal recycling center or scrapyard.