Installation: 1. For your safety, Shut down the compressor and discharge or shut off the air 2. Turn the Knob (handle) counterclockwise to depressurize the spring. Open the regulator body by loosening the (4) Allen screws (Before you open the body, mark the flow position for reassembling) 3. Replace the Diaphragm. Clean the surface of any moisture or particulates. 4. Reassemble the regulator body and Turn the Knob (handle) clockwise to pressurize the spring.