Duo30-90 The problem appears to be electrical arcing around the outside of the burner casing. This appears to occur about every minute, then stops and does it again about a minute later. There's a flash. Have just switched on the system after ten months. It's ten years old, cleaned it out last year, and is very rarely used. It's never done more than about sixty hours continuous running.
Any help really appreciated - it's cold and it would be good to switch it on.
It seems like an earthing problem. Could the earth have become ineffective?
