A/C r134a Portable Refrigerant Recovery Machine Air Conditioning Equipment 1. Device description : WDF-X530 is an automatic model without any manual valve. This model can do a good job of recovery, Vacuum, and charging. It provides users’ friendly menu. You can choose the process you want, and just one key will help you to complete the process. After that, there will be an audible alarm for you. Also, it can do job of oil draining and oil filling . After recovery , waste oil