Your compressor is largely maintenance-free. There are two attention points:
1. Is there still enough oil in the engine?
To check this you have to look into the glass eye of the compressor. There are two lines, one on min. and one on max, and the oil-level should be between those lines. If that is not the case, the oil has to be filled up. For the precise description of the filling up, please look into the service-manual of the compressor. (this manual can also be down-loaded).
2. Is there any condense in the pressure drum?
There is the possibility that your pressure drum will fill with condense water out of the area. In the long run, this can harm the air cylinders. We advise you to open the pressure drum valve regularly (please hold a cup under the valve outlet to catch any expelled fluid).