I've a, new for me, 2006 Lunar caravan and am very pleased so far coming from a much older van.
I think I have a thermostat issue with the electric blow air heating. It only comes on when the thermostat is set at the higher temperature settings 8-9-10. Below 8 the heating does not turn on, I've tried many settings.
I'm actually controlling the internal temperature of the van by changing the power of the heater (500W, lower settings etc) but putting it on the 8-9-10 on the thermostat.
It depends on the internal temperature of the van - If the van is already warm the thermostat will do what it is supposed to do. Stop the heating coming on.
If you are correct and there is a fault - it could be the switch. If it is a mechanical switch (ie not digital) You may be able to clean it by spraying it with WD40. That is - if you can get in to it. Apart from this - I can't help.
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