Because an oil-free rotary vane pump uses no vacuum oil, servicing shifts from oil changes to three things: inlet air, cooling and vane wear.
Set the inlet filter replacement interval from the duty. In a clean workshop it can follow running hours; with powder or fibres, shorten the interval and check the element for damage. A clogged element reduces effective pumping speed directly — pump-down slows and the pressure will not come down.
For cooling, leave at least 10 cm of clear space around the body and avoid long runs inside a sealed enclosure. Lower the working pressure when ambient temperature is high. Vanes are the wear item: if capacity drops, noise rises or vibration increases, stop the unit and inspect vanes and chamber, then replace as needed.
Check lines and joints for leaks before start-up each day, and inspect electrical connections and earthing each quarter.