Worceter 240 combi permanent hot water even when tap not on

[davphi338]

Hi,

My worcester 240 combi tripped via the overtemp sensor. When reset the boiler fires up even though the boiler is set to hot water only and no taps are on. Needless to say the boiler trips again due to overheating. I have removed the flow micro switch from the divertor valve and it seems ok. On looking at the pin on the diverter valve it doesn't seem to move if I turn a tap on or not and when the micro switch is re-installed the pin on the diverter valve is activating the flow switch causing the boiler to fie.

I'm presuming its the diverter valve which needs replacing I would just some clarification from people more experienced than myself.

If I do need to replace the diverter valve will I have to re-pressurize the expansion tank to 0.5bar, if so how do I do this.

Thanks for any advice

 

[croydoncorgi]

Yes - the diverter valve is stuck in the 'hot water' position.

Yes - probably most effective, quickest and cheapest option is to replace it, not repair it.

If my memory serves, this boiler is infested with O rings and tends to leak after re-assembly. Not a DIY option.