My Potterton Performa 24 combi. boiler will switch on and fire up, but will not switch off. For example: If i turn it on to heat the water only, it will heat the water, and then heat the central heating system. It will try to cut out, but cannot manage it. Therefore, it just gets hotter. Please help.

Tracey, October 2008

Hi Tracey

Most likely to be a faulty microswitch on front of the diverter valve.

Ian, October 2008

Tracey you can't fix it as you ai'nt clever enough, just freeze

froodo, October 2008