My condenser boiler stopped working today and showed up fault F1. Gas supply fine as gas cooker working.

After a long look I found it was the condensate outlet had frozen up. I cleared the ice from the pipe and now heating working again.

The other possible faults are gas valve and full auto faulty but they were all fine. Hope this helps

Simon, January 2010

Thanks for that..I also cleared the ice from the condencing pipe (white pipe under the boiler) this pipe was full of water. but further up the waste pipe it was solid with ice..

Mike from Stockport, December 2010

blocked condense pipe ,try putting to waste inside, or outside diameter needs 2b 32mm minimum if overflow pipe

ferrolli engineer, January 2010