How to add hot water to existing Tado setup?

viperlogic

Hi all, Tado user since 2017 where have the following setup... EPH 3x channel/zone programmable control panel (2x CH & 1x HW) with a wired thermostat for downstairs and a wired thermostat for upstarts.

I replaced both original wired thermostats with Tado wired thermostats, added Tado TRVs to most rads (not all) upstairs and downstairs, and have the internet bridge. And this has worked great all these years.

I now wish to be able to control the HW via the app, rather than manually via original EPH control panel. I see the extension kit is discontinued. Also the new Tado wireless controller appears to be only 2 channel of 1x CH and 1x HW. How can I get HW added to the Tado system?

One idea I had was to add a third Tado wired thermostat and put it inline with the live for the HW, set the EPH control panel HW to always on and then can control it via the app. This good/bad idea or ?!

Or, how can the new Tado wireless controller, which appears to be 2x channel, actually control 3?

Thank you

viperlogic

Did some more digging into the setup in my house.

Boiler is a Vokera Vibe 25a, configured in S type (I think), with 3x motorized valves, and EPH R37-HW 3x zone programmer

Below is a photo of the EPH 3 zone programmer, where 1 & 2 are power, 3 is HW, 5 is CH1 (downstairs), and 7 is CH2 (upstairs)

Below is a photo of the boiler PCB with three cables into it which I believe are power, weather compensator, and "thermostat"

And here is a photo of the rats nest where boiler, valves, 3 zone EPH R37-HW programmable controler, etc all come back to!

A few questions!...

Option 1

• Can the new Tado wireless controller replace the EPH zone controller entirely?
• If so, how would it be wired as the Tado controller is only 2 zone whereas I need 3? Would it be that the Tado controller does 2 zones and for the third zone solely uses the wired thermostat?

Option 2

• Just have the new Tado wireless controller handle the HW and leave the 2 CH zones as is
• Source new power to the Tado wireless controller or use power from the EPH controller?
• Remove HW (location 3 in EPH) and extend it to run it to the Tado wireless controller?

Any ideas or suggestions @MikeRanger or @majik9911 as believe you may have done something similar as per here

Thank you

hugbilly

I don’t know how heavily you’re invested in tado°, but Wiser make an off the peg 3 channel system which might suit . . .

majik9911

Hi @viperlogic

So I had a similar setup but not a Vokera boiler - so there might be limits. From your question:

Option 1

• Can the new Tado wireless controller replace the EPH zone controller entirely? Yes, from my post (in your comments) I replaced my 3-channel controller by giving CH1 and HW the controls in the Tado Programmer, which then goes to the Wireless TS. Then I used the existing wire for CH2, connected to L on the Programmer to give a permanent live, which connected to a wired Tado TS in a different part of the house. This doesn't mean that your system will be the same, however, so proceed with caution!
• If so, how would it be wired as the Tado controller is only 2 zone whereas I need 3? Would it be that the Tado controller does 2 zones and for the third zone solely uses the wired thermostat? Yes, as above. I outlined my solution in the link you shared, so hopefully that can be useful to you.