Just like the OP, we are trying to come up with a solution to get hot water without running the engine. We are increasing our solar bank (from 200 watts to 695) and have an immersion which we wondered whether we could run using the solar only.
We also have Webasto central heating but did not know that it is possible to use it for hot water only. Are all set up's likely to be like this or in some cases would we need to switch off all the radiators to achieve the desired effect?
If there is a valve on our Webasto, where would it be located - in/on the engine, near the radiator tank or near the motor that runs the CH? And what does it look like - if anyone has any pictures that would be brilliant.
Thanks in advance.