circulating pump constantly running

I have a icos he15 condensing boiler on a indirect vented system, the system has been in for 8 months and has drayton programmer set up for the DHW the heating, the trouble im having is that the airing cupboard is in our bedroom and even when boiler is not programmed to heat the circulating pump is running all night and is becoming quite noisy due to it always running, the problem seems to occured over the last week, hopefully you might be able to point me in the right direction as to solving this problem and if you require more info i'll try to be as helpful as possible. cheers

when boiler is not programmed to heat

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Just to clarify .. A call for hot water is also a call for heat

No 1 suspect on my list is a wiring fault. Maybe a faulty programmer
A lot depends on your system layout and wiring so another possibility is perhaps a frost stat or pipe stat could be calling for heat.

It would be a case of tracing the wiring back and seeing where the live that powers the pump is coming from.

slug, clarify me if i'm wrong, but it could be the pump overrun stat??