Tado not calling for heat - no extension kit

TalkingTado

Hi,

I have a Vaillant Combi boiler. I have a 3 storey house. I replaced the wired thermostat on the ground floor with the tado wired thermostat. I have wireless tado thermostats on the middle and top floors with Tado smart TRVs on all rads, link to their respective thermostat (on the same floor). There is no extension kit.

All appeared to be working fine until I lit the wood burner on the ground floor. Ground floor was above temperature but the middle and top floors were not so they said they were calling for heat. But all rads remained cold.

It was my understanding that the wireless thermostats would use the wired one to switch the boiler on/off but it appears the wireless ones only seem to control the TRVs (I hear them open but no heat).

Have a got some config wrong or do I need extra kit, like an extension kit next to the boiler?

Any help very much appreciated.

Regards

Tony

policywonk

It is possible that the wired thermostat originally directly controlled a zone valve, so when that thermostat turned on, it switched the zone on and that zone valve then created the call for heat. Do you have a zone valve doing that?
If so it may be that the Tado controller is wired by your wiring centre to only act as a timer, and the Tado thermostat switches the zone valve on, calling for heat from the boiler.
You may need to review and revise the wiring logic so that the Tado controller *directly* calls for heat and switches the zone valve itself. The wiring from the Tado thermostat is then used to determine the logical rooms being heated.

TalkingTado

Thanks for the suggestion policywonk. It turns out I hadn’t set the ‘Zone Controller’ for the particular room (floor) in tado. Once I set them to the wired thermostat it is now all working as expected.

Thanks again