William, you stated:

<< Since I just bought my van a month ago I want to get the inside
clean...>>

Since you have no idea what the PO's sanitation habits were, first off,
I'd wash the tank, sponging down the walls using dishwashing detergent.
Running some of that detergent and water solution through the faucet
won't hurt.  Rinse well, of course.

   The following step I do annually, if not more often.

Add diluted chlorine, about 1/4 cup per 10 gallons, to the half filled
tank.  Fill it up and let it sit a while, say three hours or so, maybe
even drive the bus a bit to get a good slosh going.  Empty the tank by
pumping it through the system.  Finally, fill and drain the tank a few
more times with fresh water, to make sure that you have rinsed all of the
chlorine out.  If you wish, you can use a baking soda and water solution
to remove the possibility that there's any leftover taste of chlorine,
but I generally don't bother with this step, since we use a Brita pitcher
to filter all of our drinking water.  After a trip, I drain the system in
order to prevent nasties from growing in there.

     George/ATL
     '89 Westy, Wernher
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