My potterton suprima 60l keeps heating the water despite the control panel being off. It fires up for about 3 seconds and then switches off but does this constantly. The only way to stop it is to switch off at mains. its not effecting the heating.

Please help???
Thanks

Sammy, November 2009

sounds like the boiler is getting a stray live from the hw motorised valve. get replacement head for hw valve.

ste, November 2009