linea 726 making noise overnight though CH off

[superbantam]

I moved into a new house at the end of last year which is 5 years old & has a linea 726 boiler installed.

Recently I've noticed that it is making a noise overnight, which is waking me up, but when I've looked at the boiler it doesn't seem to actually have fired up - the noise lasts about a minute and occurs every 45 mins or so.

I'm not sure if this has been happening since I moved in and I've just noticed, or has just started (maybe the frost protection as it's cold out, but I'm led to believe that frost protection would fire up for around 20 mins at a time).

This leads me to thinking it's the DHW preheat function, though I'm not sure.

If it is, I know I can disable this with jumper 6 on the PCB, however I don't know where this is located in the boiler (I can't see it in the installation manual) or if it's easy for a novice to do (thought I'm not untechnical).

Can someone advise if this is the likely problem or not, and if so give me some tips on removing jumper 6.

Thanks.

 

[scatmanjohn]

Sounds like that is the problem (pre heat)

On the cover over the pcb is a diagram.

It shows the layout of the pcb.

You will find the position of jumper 6 on there. Just pull it off

 

[superbantam]

Cheers scatmanjohn.

I'm still puzzled as to where in the boiler the pcb is located, is it behind the control panel somewhere - I'll admit I've not taken the boiler cover off yet, it might be obvious!

Also, am I right in saying that the preheat is done by an electric coil or something then? As I don't see the boiler firing up?