Arkansas HVACR NewsMagazine February 2018

S tate, National, Chapter News Tech News

with R-453A without any lubricant or hardware changes. Also, the same equipment can be used with R-453A as with R-22. THE RETROFITTING PROCEDURE Below is a brief list of retrofit guideline procedures for converting an R-22 system to R-453A. As with any refrigeration or air conditioning system being retrofitted, always follow the detailed retrofit guidelines from the equipment or refrigerant manufacturer. Establish baseline data with temperatures, pressures, super- heat, and subcooling; Record compressor oil level and No oil change is needed. However, if polyolester lubricant is used to replace the mineral oil or alkylbenzene lubricant already in the system, replacing the o-ring seals before starting the system is recommended; Evacuate the system to 200 microns, and charge the system with R-453A to 90 percent of the original R-22 charge; Start the system, and take a system check. Record pressures, temperatures, superheat, and refrigerant charge; Recover the R-22;

subcooling. Compare to baseline data. Adjust the thermal expansion valve (TXV) pressure controls, evaporator regulator, and/or condenser controls to maintain desired temperatures; Check the system charge, and add refrigerant if needed to reach the original charge level; Carefully monitor the oil level in the compressor. Add or remove more oil if required to maintain the correct level; In system with receivers or long and complex piping where oil return to the compressor could be an area of concern, the replacement of up to 25 percent of the oil charge with a polyolester lubricant is recommended; Check the system for leaks, and Label the system with the new refrigerant. (This article was condensed and “Reprinted with permission of the Air Conditioning, Heating, Refrigeration NEWS,” www.achrnews.com ACHR NEWS is rich in content and we recommend Arkansans to subscribe.)

R 22

R 453A