F40 Forelli fault code?

Hi, I wonder if you could help at all. I have a Ferolli HE18ov boiler and it is coming up with an F40 error on startup. This seemed to happen after I was trying to put the boiler into eco mode and I think its something I have done to the programming but I have not idea how to reset the programming. Would this cause the issue and do you know how I reset these boilers? any help would be greatly appreciated.