Quote Originally Posted by G4RHL View Post
But I have OpenTherm connected and the Manual says to use Eco mode with OpenTherm in order for OpenTherm to learn. I wonder if anybody has come up with an easy way t provide backup power to the clock on these boilers>?
In ECO mode my Intergas boiler simply keeps track of when DHW is required, so if the hot tap was run at about 8:00 am over the previous 2-3 days, the boiler would ensure pre-heated DHW is available today at a similar time. The boiler 'remembers' DHW usage thoughout the day in an effort to ensure heated water is available at the predicted times.

I think the ECO learning days can be set between something like 3-10. I haven't set the boiler's clock but the function still works OK for me.