Tado for multiple heating zones and hot water with tank

AK82

Hi

I recently moved into a property where we have 3 zone values 1 for downstairs, 1 for upstairs and 1 for hot water tank.

I installed tado wireless kit with 3 TRVs but it failed to work as it was constantly heating the radiators and hot water stopped working.

Checking on tado support website, I can see that I need a wired starter kit with an add on wired thermostat. But my understanding is this won't work fir hot water. Is that correct?

So what would be a solution for my heating and hot water system? Please advise.

Can I just add on wired thermostat to the wireless starter kit. Will it work?

Thanks

johnnyp78

Depending on how it’s wired, one wireless receiver to zone valve and hot water, plus one wired thermostat should do it. If not, one wireless receiver to hot water and two wired thermostats to each zone valve.

AK82

Thanks @johnnyp78

I have 1 line 1 neutral and 2 wires (grey and black) for hot water from the boiler. It's currently connected to honeywell controller which controls the heating zones and 1 hot water zone valve. I also have 1 honeywell wired thermostat downstairs and 1 honeywell wired thermostat upstairs to request heating for each zone.

If I go with adding one wired thermostat to the wireless kit, how will it work for 2 heating zones? Should I just replace only one wired honeywell thermostat and leave the other one wired. Please advise?

Or should I just add two wired thermostats to the Tado wireless kit?

johnnyp78

Adding two wired thermostats would probably be the easiest option. I presume you have a junction box? If you do that you can leave it in place, otherwise you’d to rewire.

AK82

Thanks again @johnnyp78. Will give it a go and see if it works. Appreciate it.

I dont have a junction box. Do you mean the small boxes to connect the line and neutral wires?

johnnyp78

The box to connect the wires between your zone valves and boiler.

AK82

@johnnyp78 - My understanding now is, to connect all the wires which are now in Honeywell controller (line, neutral, black and grey) to the wireless receiver near the boiler just like what I had before and replace the two honeywell wired thermostats with tado wired thermostats.

Is this your understanding as well? Meaning I don't need a junction box as the zone values are all plumped into the boiler already and just the above 4 wires are coming out of the boiler. Probably I can use S Plan wiring plan?

johnnyp78

I’m guessing the Honeywell controller is the junction box. It it’s a three channel controller it’s going to be more complicated because you can’t do a direct replacement with Tado, which only has two and one channel controllers. If you don’t want to rewire you might need to leave the existing controller in place, set to always on, leave it to control the hot water and just replace the two thermostats with Tado wired thermostats.

AK82

Ah ah makes sense. I didnt think that way before. May be this is why my wiring didn't work with just replacing the honeywell controller with the tado wireless receiver.

So this way, my hot water will be always on in Honeywell controller and my heating can be controlled using the two tado smart thermostats with one internet bridge? Not sure if this will cost my gas bill to go up 😬

johnnyp78

No, the heating is set to always on in the controller, taking it out of circuit and allowing the two Tado thermostats to control the boiler through it. You control the hot water on a schedule, as before.

AK82

Sounds interesting and looks like a good option which haven't thought before.

However, if I want to control the hot water using tado, is it possible to use wireless receiver along with 2 wired thermostats? Please let me know.

johnnyp78

Yes it should be, but will require more rewiring because you’re replacing a three channel programmer.

AK82

Thanks @johnnyp78. Do you know what sort of wiring is required? Any link for video or diagrams I can refer to. Please advise. Appreciate all your advice so far. Much appreciated.

johnnyp78

If you search through the forum a lot of people have asked about similar setups. I would start there.

Adinx

@AK82
I had a similar setup with a hot water tank where the hot water and downstairs and 1st floor heating zone was controlled by a TPOne B and my 2nd floor heating zone was controlled by a TPOne M wired device. I got a wireless starter kit with hot water, 8 SRVs and an add on wired SRT. I replaced the TPOne B with the wireless receiver with hot water control and replaced the wired TPOne M with the add on wired SRT. Both zones work independently and I can call heat from any of the SRVs. One thing I had to do was make ask tado to make the wired SRT a zone controller.