I am heading to the dark side!

I think we burned a bit of diesel keeping the boat warm with the heating!

Quite possibly! Just visited our boat and was surprised to see that the Webasto has got through half a tank of diesel stopping the plumbing freezing over the last few weeks!
 
So whats that in litres?

probably about 50!

We did spend a weekend on the boat which would have got through a bit more, but most of the time it has been set on minimum thermostat - an electronic thermometer in there shows that it has been keeping the temperature above 5 degrees.
 
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