Roger Goulden has forwarded the following information:-

I raised questions about odd performance of the 12 volt electrics at my last habitation service, but no faults were found.
Then suddenly, I could not charge the leisure batteries. Connecting up to mains, only the leisure battery light on the control panel came on. No charging - and a possibility that the batteries were actually discharging. Luckily charging though the alternator worked fine and both charging lights came up.
After extensive and helpful phone calls to Lowdhams Nottingham - and buying a voltage tester - I established to my own satisfaction that the Calira charger on my 2005 Sunliner 608L was indeed kaput. They wanted £800 for a replacement!!!
I charged the leisure batteries in situ with my venerable Bradford-built charger that usually looks after two six volt batteries on my MGB.
Googling produced a likely source for Calira chargers in North Wales.

www.atlanticmotorhomeservices.co.uk
The site has loads of information about batteries and chargers. I emailed and had a friendly reply from Allan Evans.
We exchanged several useful emails while I considered what to do. They are an official Calira supplier with prices of new and remanufactured units on their current stock page. They post out or fit. Eventually I decided to take my van to North Wales - and visit friends living close by - in case just changing the Calira didn't solve my problems.
We agreed an appointment. I went for a Calira rebuilt charger.
The charger just drops in after undoing a couple of wing nuts, so the charger was replaced. Batteries charged up fine.
Allan spent a while looking things over and asking me to make sure everything worked. I was happy.
His website suggests that overload is the main reason for charger failure. GIven a long history of charging-related issues - including melted fuses on the leisure battery charger circuit and a blown alternator - Allan suspected my batteries might be faulty.
He doesn't sell batteries, but strongly recommends Bosch SC Car batteries - as lighter and better performing. I couldn't find a supplier who would give me the 5 year warranty if I fitted them as leisure batteries.
Today I've fitted a pair of Varta Leisure batteries - mainly because they are exactly the same dimensions as the pair they replaced. They are now charging via the Calira charger on mains hookup. I made sure they were both up to same same voltage before fitting them
On our next trip I shall find out if there are still problems with the electrics… But I shall take my old charger with me. If the Calira packs up, I can disconnect it and carefully thread an extension lead behind the cushions, under the false floor and into the battery housing so I can charge from a mains hook-up!!
Have a look at the website if you have any electrics related issues. Allan is clearly very knowledgeable and understands the technology.
In March 2013 they begin operations from their new premises that were being painted out while I was there. He is also inviting a group of other tradesmen to set up in the same building so should be in a position to offer a useful range.
Finding Allan after several fruitless Google searches solved a big problem at a reasonable price.
I would certainly recommend him. I hope he does well in his new business. 
 

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Martin Iles has let us know about the following:-

Just to let you know I have found a dealer that can repair Calira chargers at reasonable cost. The main common fault is a burnt out circuit board which fails and prevents charging when on a mains hookup. They replace the offending circuit board with a more robust unit which also has a fan fitted to keep it cool. Repaired mine for under £170. The company is Davan Caravans near Jct 21 M5 Weston super Mare.

Of all the problems with Knaus motorhomes the Calira EVS 12v supply and charger unit apperars to cause more problems than anything else. Many of us are now on our second or third units under warranty. I believe that a new unit is is the region of 600 euros once out of warranty.

A Knaus owner in Ireland (Liam O'Gogain) has noticed that one difference in the latest model of this charger is an uprated capacitor. He has kindly supplied the photograph below. There may be other, less obvious, differences.

At the moment I have recieved no reports that replacing the capacitor actually fixes the charger. Should anyone know of a source of supply for the capicitor please email webmaster@knausowners.com and I will add the details here. 

Disclaimer

Any attempt to repair this unit is at the owners risk and should only be undertaken by a suitably qualified person.

Kevin Hamblin - Knaus Owners Club

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