Key Points for Proper Refrigeration System Oil Replacement

First, completely and thoroughly drain all old oil from the crankcase. After draining, flush the system piping with new refrigerant oil of the same model to remove oil sludge, wear debris, and aged carbon deposits adhering to the pipe walls and cavities. Upon completion of flushing, replace the oil filter and dryer filter to eliminate moisture, acids, and solid impurities within the system. Finally, add new refrigerant oil of the specified grade in the quantity indicated on the equipment nameplate, while also performing vacuum pumping and leak detection procedures.

An incomplete oil replacement is as good as none.

Residual impurities, acids, and degraded products in the old oil will continue to contaminate the new oil, directly causing rapid degradation of the new oil. This significantly reduces its viscosity, lubrication, insulation, and anti-wear properties, accelerating wear of bearings and seals, and potentially leading to faults such as bearing burning, filter blockage, and system acidification.