How many devices does Tado support?

Tado appears to support up to 25 devices:

However, I currently have 29 devices in my Tado system, all of which are connected and appear to be functioning correctly in my Tado app.

However, I have not yet been able to complete my setup. I have two underfloor heating circuits and a radiator circuit. Currently, Tado is controlling all the radiators individually, using a combination of Smart Radiator Thermostats and Wireless Thermostats, and that seems to be working fine, but the hot water radiator circuit itself and the boiler is simply on all the time.


  • Since posting, I have discovered that while I have 16 rooms configured in my app, only some (presumably no more than 10) are connected to the Wired Smart Thermostat I have, which itself is acting as a zone controller. This might explain the 10 room limit in the documentation. As it happens, in my case at present the limit is irrelevant, because I have the radiator water running 24x7 and for the rooms not linked to a zone controller the temperature control is working just fine. That will change as soon as I have worked out how to control the balance of the heating system. I still don’t yet understand the 25 device limit, the effect of which I have yet to experience.

  • I believe that the 25 device limit on the Tado network is a limitation to do with the radio / communication protocol that Tado are using. We got over this problem by reducing the number of Tado devices on the Tado network. We kept the TVRs on the radiators and removed the need for Tado wireless temperature sensors. We developed are own wireless temperature sensor that works over WiFi and uses the Tado API to interface into Tado. We developed it for our own home, but have made it available as it maybe of use to other people.

  • Wow, that could be really useful.

    I have a related problem that perhaps the API could work with. I have a radiator circuit that has a separate valve. I've set up a Smart Thermostat as a zone controller for the radiator circuit, but nearly fell off my chair when I saw that even if a radiator switches on the Smart Thermostat and activates the valve and the zone, the Wireless Receiver on my system that controls the boiler _doesn't_ switch on.

    If, on the other hand, I set the Smart Thermostat so that it does switch on the boiler, it can't act as a zone controller so non of the radiators can activate it!

    Could you develop a relay link so a zone controller would activate the Wireless Receiver?

    (I actually need two of these, to defeat the 10-room limit of zone controllers).

    A very simple change that would work is if Zone Controllers didn't have to be their own zone controller, and you could set another device (e.g. a Wireless Receiver) as their Zone Controller, making a little tree of zone controllers.

  • I have finally installed Tado successfully in my house and it’s working very well! I'm posting this in case it's helpful to others.

    Tado is controlling two underfloor heating zones, the hot water and radiators in 14 rooms. The system is using 32 devices. The radiator loop has it's own valve, and needs two smart thermostats wired in parallel directly to the boiler, to overcome the 10 room limit for zone controllers and the fact that a Smart Thermostat can't have another device be its own zone controller. I also had to engineer a bespoke radiator valve adapter because we had unusual radiators, but that was a different issue.

    The whole process took four months of trial and error (mostly due to the mechanical issue with the radiator valves, but also delays in getting information about how the system worked), but I'm delighted with the outcome. Previously, the boiler was on constantly and the house was still uncomfortably cold in places. It's now correctly switching off when no-one is home, and directing heat efficiently to the right places.

    I still don't understand the 25 unit limit, since the 32 devices I'm using appear to be working fine (and, I guess, meshing in order for the signals to span from the attic to the basement). I only hope that doesn't change.

    It's a shame that the Smart Thermostats, when acting as zone controllers, can't activate a boiler through a Wireless Receiver. That limitation still means I have two extra devices, and (I think) means I'm limited to using the analogue interface to the (Vaillant EcoTec) boiler. But, in the big scheme of things, I can live with that for now.

    It was also a shame, and surprising, that in spite of trying four potential suppliers, I wasn't able to find a UK installer inside or outside London that would set the system up as a service. Hopefully someone will step into that role someday.