Hi folks,
Just an update in case anything is useful to anybody . Tech support at truma confirmed that it was almost certainly a blower problem, although when removed I thought it appeared ok. However I replaced it and it fired up quite a few times, then stopped again, refusing to start. Unusual for me but I gat in a rage and hurled tools and old blower up the wall.
After cooling down, I removed the pcb again, ( I had earlier dried out with an hair drier), stuck it in the electric oven on plate warming setting for about 20 mins. Refitted and everything is working fine!!
€130 down, original blower, which I could have sold, in the bin. Lessons learnt.
Four days later all fine.