Well eventually i had it fixed by paying another £280 to Homeserve. It was a motherboard that has gone wrong, nothing to do with all those that had been replaced.
I wonder if any Forum member could help? My Vaillant ecoTec plus 831 was installed in 2010, in March it stopped giving out instant hot water when I turned on the hot water tap but heating up the radiators instead. I employed a plumber locally who is experienced in Vaillant boiler (so he told me) and...
