NO. Both the refrigeration system and the heat transfer system are sealed systems that do not require regular maintenance.We normally use vacuum pumps that contain oil. These pumps need to be monitored between loads, and the oil should be changed if contaminated. The FC-R 50 and 100 both have condensing coils in the back of the product chamber that will need to be defrosted at the end of the drying cycle, and after the product is unloaded.The FC-R 250 and 500 have automatic continuous defrost cycles during the course of the drying cycle. Thus eliminating the need to defrost at the end of the cycle.