[rheavn]

John,

You asked, " Do both pumps work the same lines? Or do they have separate duties?"

Your air system has three air pumps.  The 12V, the 110V and the engine compressor.

The 12V pump provides air to the 3 gallon air tank in the right rear wheel well, the air pocket doors, the air toilet(s), dump valves and slide seals (if you have slides).

The 110V air pump provides air to every air tank and air system on the coach including all items that are provided air by the 12V air pump.  The 110V air pump's air does not go through the coach's Wabco air dryer & desiccant filter.  For this reason the 110V air pump usually has an air dryer mounted close to the pump.

The engine compressor provides air through the Wabco air dryer & desiccant filter to all air tanks and systems within the coach including all items that the 12V air pump provides.

Hope this helps..............................