At 09:50 PM 7/22/2008, Scott Daniel - Turbovans wrote:
>but on 12 volts driving - only drove 30 minutes so perhaps that's why it
>doesn't seem to do much.
>I did check that the relay under the seat energizes and suppies power to one
>of the fuses behind the driver's seat when the alternator is charging.
>so is that 'just how they are' ? ..........ie. very slow in the 12volt mode.

Scott, half an hour isn't long enough.  Takes about that long to get
the cycle running well after it stops.

The 12v heater is just as powerful (85 watts) as the 110v one, but
it's much more susceptible to problems from poor connections, because
you're pushing 7.5 amps through the circuit.  So every bit of voltage
that appears across wires, fuse, connectors etc. will
disproportionately take away from the heater.

Also, the fridge simply doesn't work as well on the road because of
the same sloshing effect that keeps the boiler from going dry.  So
for a true comparison you need to be standing still.

--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage," '85 GL "Poor Relation"