Bj�rn,
If your Vanagon camper is a Westfalia then the Dometic fridge is wired to the
12v system by way of a relay. This relay provides 12v to the fridge only when
the engine is running. You can leave the fridge permanently switched to the
battery setting without ever worrying about draining the battery.

> <snip>  Don't leave it in for too long without the engine running, it is as if
> you leave the headlights on. <snip>