how to stop reset button activating on Sterling 40 ST108PL?

Hi

The red light reset button on our Sterling 40 ST108PL oil boiler sometimes comes on, which means the boiler doesn't work unless we physically reset it. This means from now until about April if the heat doesn't come on overnight the house is really cold in the morning.

We've had 2 boiler experts look at it, the control box was changed, but the problem still occurs, and the experts can't see anything else wrong. The boiler gets serviced every year.

It seems to cut out as soon as the timer in the house starts - it doesn't seem to cut out during a timed, or turned "on" setting.

Could it be electrical or something?

I hope you can help please!

Thanks

Alan