Wired Smart Thermostat with Extension Kit - My installation Story


The following is for info for those installing tado into a conventional UK environment with a single wired thermostat in the Hall or Lounge and hot water provided from a conventional hot water cylinder. The reason for posting is that although the tado install is at first sight well documented you may encounter problems and it is not always clear why things go wrong. Comments welcome.


1 I installed a wired Smart Thermostat to replace my old Drayton wired thermostat in the Hall. All my radiators bar one (in the Hall) were equipped with conventional Honeywell TRV's. My old Drayton Hot Water and Central Heating programmer was located next to my Worcester 40i Conventional boiler. I plugged my tado Bridge into the back of my Router in the Lounge. AOK no problems found.

2 I installed the tado Extension Kit to replace the Drayton programmer next to the boiler. Again AOK. The only difference being that I could turn the Hot Water ON/OFF from the Smart Thermostat. All programming had now to be from the tado app or my PC.

3 I started installing tado Smart TRV (STV)'s. No more than one per room. The Hall still having a radiator without a TRV. I have a large house and this is when I first started having a problem in that remote STV would not connect to the tado Bridge. To cut a long story short I solved that problem by location my Bridge in the centre of my house downstairs connected to a Netgear remote access point. Once the connectivity was resolved I succeeded in installing 10 STV in 10 rooms. AOK but I noticed that the default for my tado system was that when STV's call for heat the boiler does not start until the Smart Thermosat in the Hall calls for heat.

4 Having established that I have a boiler bypass valve and a bathroom towel rail which is always on I fitted an STV to the remaining radiator in the Hall.

5 After some research I asked tado to configured my system so that when any STV calls for heat the boiler will start. In effect the CH relay in the Smart Thermostat remains permanently ON. Thus for all calls for heat the Extension Kit will turn the CH on and the boiler will start.

6 I then added additional STV in my Lounge and a Smart Wireless Thermostat which in the tado App I configured as the Measuring Device.

Again this works fine although I don't fully understand how it controls the three radiators each of which may or not be calling for heat. I have a gas fire in the Lounge also.

My conclusions? The tado system once configures works very well. I am not sure I am happy with the tado Cloud controlling my system remotely but that is the way it works. I have had one hiccup when I woke up to no heating. This I eventually attributed to the Smart Thermostat not switching the CH relay so I have directly connected NO to COM thus bypassing the relay. (If you do this you should get a qualified electrician to do it)

I am still playing with the schedules to optmise my dailing heating demands. In 10 rooms I now have 3 x Thermostats and 16 STV.