Ecotec plus 831 Vaillant Boiler - Heating always on

[Brin007]

Hi folks,

Need some of your experstise!

We have had a new PCB board + diverter valve fitted to the boiler, since then the heating seems to be always on. I have resynced the thermostat (Drayton digistat SCR) and I can see when I turn up the heating or down the thermostat is communicating successfully as the lights on the Drayton digistat turn green etc. But this has no impact on the boiler.

I have also checked the settting on the boiler is set to heating always on rather than timer.

Any ideas?

Thanks

 

[trojanhawrs]

Is there a setting to turn the boiler controller off? Your external thermostat should then override when required

 

[Brin007]

I don't think so. The heating on the boiler is controlled either by selecting the timer schedule option or selecting heating always on.

We have the boiler setting on heating always on then controlled by the thermostat. But since the new PCB board was fitted whenever we increase or decrease the heating on the thermostat this doesn't talk to the boiler although I can see the Drayton digistat scr is going green when getting the call for heat and the light turning off when we lower the heating.

 

[trojanhawrs]

You should get the installer back if it's not working right, the next stage would be checking voltages with a multimeter

 

[Brin007]

Yes that is the plan although the installer has gone on holiday for a week!

Thought I would ask in here just in case it was something obvious.

 

[jeff the gasman]

Remove the low voltage link

 

[CountryFan]

We have had a new PCB board + diverter valve fitted to the boiler, since then the heating seems to be always on.

You should get the installer back if it's not working right

Or just

Remove the low voltage link

 

[Brin007]

Remove the low voltage link

Thanks Jeff removing the low voltage link did the trick!!