How do we fix a Ravenheat CSI85T condensing boiler?
The boiler hasn't been used much since it was installed 14 months ago. The water heats up but the display for the central heating keeps going blank so the dental hating cuts out. The problem is the timer display works when it's showing but not when it is blank. On the odd time it works the central heating goes off after 30 minutes. Never for longer.
Samantha, January 2015