I know it's off topic, but this is Locostbuilders, there's always an answer.

The new Zilbus has a Webasto water heater in it. It is primarily used to heat the engine quicker, but can be upgraded via some controls to provide heat to the interior of the vehicle with the engine and ignition completely off.
Seeing as we would like to press the vehicle into basic 'camper' duties (The back is plenty big enough for sleeping in), it seems that some sort of leisure battery and charging circuit makes sense to run the leccy side of the webasto and leave the main battery well alone for such frippery as starting the engine in the morning.

Any DIY campervan builders out there who might have experience of a suitable layout for the leisure battery ?

Anyone with experience of the Webasto heaters ? This one works fine, but needs the control circuit upgrade to keep the interior toasty with everything else off.

A split charging system would be best, with an additional high Ah high capacity battery.
With this, you could also put a photovoltaic (solar) system on it to charge it when using it during the day. this will save having to start the engine to charge the battery.

I used a split charging relay in my old camper to charge a leasure battery to operate telly , fan etc . Worked well. Not sure how good a solar panel would be ? Might be worth looking at a wind driven generator ?

I did a home brew camper about 15 years ago, in terms of split charge circuit it is nothing more than a common or garden relay that links the cars main ignition/charging circuit to the leisure battery. I used a relay from a VW which only operates when the ignition is on, this then charges the leisure battery, when on site the leisure battery is 'disconnected' from the main circuit meaning that it cannot flatten the car battery, obviously all fridges/lights are connected to the leisure battery.

Hope this makes sense, sorry can't advise on wind or solar power.

Regards

Frank

I think the more modern split charge relays work disconnect the secondary battery from the charging circuit when the voltage drops below a certain level.

http://scottishvanners.50.forumer.com
there are a lot of guys who do campers on this forum
and loads from around cumbernauld.
and this
http://www.campervanconversion.co.uk/campervan-electrics.html

Or just connect it to a mains power supply outside a block of flats in Kent...

I'd have thought connecting a couple of diodes between the leisure battery and the alternator would have sufficed, so power can go to charging but that battery would do nothing for the engine.