If the aux battery is being drained while powering the Dometic and
driving, then your relay connection is suspect. When it works, it
connects the aux battery to the engine battery, and the engine battery
bone is connected to the alternator bone. There's no way that battery
will drain when it's connected to the alternator.

--
Rocky J Squirrel

On Tue, 2010-09-21 at 10:35 -0400, Jack R. wrote:
> The problem is that with the relay, the aux battery does not seem to
> charge
> as quickly as the main battery, and will in fact drain when running
> the
> Dometic Fridge even when the van is running.