underfloor heating pump control


Hi. I have a wired room thermo controlling boiler via digital controls. I also have wet underfloor heating that comes on via a flow item sensor so that when heating turns on and the underfloor heating sensors detects heat, it switches on. I would like to control the UFH with tado.

I believe I cannot use the relay on the existing themo as only digital OR relay works at any time.

So wonder the best way to connect the UFH pump to tado? Another slave thermostat attached to the UFH pump? A bit inelegant. And can the themo in relay mode be used to switch a small pump on and off directly (max 43watts)?

Or via a wiring centre, so existing Wired themo sends digital signal to centre and that digital signal goes on to boiler (WB 42CDI) and a relay switches on the UFH pump? 

any thoughts much appreciated. I have searched, but nothing found that relates closely to my set up. And a bit of confirmation needed!




  • dark1618

    Hello James,

    I'm wondering about quite the same.

    I bought 1 Tado Wired Starter kit + 3 Add-on Wired Tado to control 4 UFH zones. I'm planning to control the motorised valves with Tado. I have no radiators, only wet UFH.

    Motorised valves of Zone #2, #3 and #4 can be controlled with the 3 Add-on Wired Tado. But in case the Wired thermostat can only send digital signals to the boiler then I don't know how to open the motorised valve for the main Zone #1. (It can happen that Zone #1 would not need heat while Zone #2, #3 or #4 calls for heat.)

    Did you find any solution in the meantime? I appreciate if you share your ideas.

    Thank you!