Mixed System with UFH - Wiring to Manifold

Adium

Hi,

My plumber is in the process of installing Tado for my new heating system, which consists of:

• Boiler (Vaillant ecoTEC plus 630)
• Megaflo/Hot Water Cylinder
• Radiators for the loft and first floor
• 3x Wet Underfloor Heating zones for the hall, kitchen/diner and utility/bathroom

I was told by Tado support that my system is compatible and that I would need a starter kit with an extension kit to manage the radiators/hot water, and 3x add-on thermostats to manage the seperate UFH zones.

Am I right in thinking that the thermostats controlling the UFH need only to be hard wired to the manifold to control the actuators/zone valves for the three seperate zones, but then this is the only wiring required? Hence the hot water/boiler will be turned on when needed through the wireless connection between the three UFH thermostats and the extension kit?

I've looked through the manuals but I can't find any wiring diagrams in regards to underfloor heating - can someone point me in the right direction please?

Thanks in advance!

FlorinO

I have mostly the same configuration. My boiler is OpenTherm, 3 UFH zone, 5 radiators upstairs.

Tado said it would be compatible.

First of all after you buy everything and start installing you need to talk to Tado because the smart Thermostat that you buy with the extension kit is hard wired to NOT switch. No matter what you save in installer menu, it will not switch, only send data to the extension kit.

Secondly, after setting this up, my boiler Bosch Condens 2000, as soon as a call for heat was requested by the thermostat, it entered into d5(short circuit) error mode. I am still waiting for over a week for a reply from Tado.

The smart radiator valves on the other hand work well and can start/stop the boiler without problems.

I also tested a Nest on OpenTherm using same wiring and SAME wires and it works without problem on my boiler.

Adium

FlorinO I'm slightly confused as you're posting the same information multiple times onto this but none it is actually answering my question?

I think I've now resolved this through Tado support, who have advised me to purchase a Heatmiser UH4 and actuators to control the UFH manifold, and the wiring will then be between the UH4 controller and Tado thermostats.

I'll post a final update once we've got this setup and running.

AdyR

I have UFH in my kitchen and, as you suggested, I control the pump and zone valve from the relay output of the Smart Thermostat and that calls for the boiler wireless via the extension kit.

If you have three zones with just one pump then you need to find a way for any of the thermostats to switch the pump on but just the relevant zone valve. Maybe that is why tado recommend the UH4 controller.

larastafarian

Hi Adium,

Would you have a wiring diagram for using the UH4 & Tado extension kit

I also have smart theromostat valves in rads up stairs & wish to control H/W I’ve asked Tado for this but just directed me to the pro installer schematics

Cavester

Wires just go from the Tado wall thermostats to the UH4 controller as per the UH4 instructions same as any other thermostat. Nothing else required for UFH.

JayShavdia

I have exactly the same setup with my vaillant eco plus boiler and a heatmiser uh4 wired to my manifold. I have 3 under floor zones but only 2 thermostats which they say work.

How does this all wire together? Is there anything special required for the extension kit connection to the boiler? Is it just the regular connection there and then wired thermostats to the uh4 actuators?

JayShavdia

I got a reply from tado saying that the extension kit needs to be wired via relay - Any ideas?

cjcraigj1

Hi

We are just working out a very similar setup...

Would this diagram be correct using a UH4 then? (Diagram was thrown together quickly so ignore the crossed lines a line colours)

Will the UH4 work correctly without the 'N' on the wired thermostats?

Boffinboy

I know this is an old thread, but did your wiring work? I have the exact same with a UH8 and need to figure out how to wire the wired room stats

Nick_Howard

I have a similar problem, so interested in this thread

Szabolcs

Hi all! @cjcraigj1 is your above setup working fine? Thank you.

Vilmos

I would be also interested if the wiring above is right for UFH as one of the zones used in combination with Tado. Thanks.

d10brp

I had a non-Heatmiser UFH system and wanted to link it to my Tado setup for all the other rooms and hot water. I couldn't achieve this with that system (Hep2o 16 zone) so I:

• Replaced Hep2o wiring centre with Heatmiser UH4
• Replace actuators to ones compatible with the UH4
• Wired a dumb Heatmiser thermostat to the UH4
• Tested the system, verified it worked
• Bought a Tado wired add-on thermostat
• Followed the instructions in the app to replace the dumb Heatmiser thermostat with the Tado add-on

The Tado step was really easy, the app asked what stat I had already and gave me simple instructions for wiring in the Tado to replace it.

MrTooom

It's crazy how little information there is for the setup of UFH with Tado. We're installing a brand new UFH in our building that already has several Tado radiators and I've been searching endlessly for some recommendations. This seems to be the most concrete info I found. I'm so surprised that Tado has no documetation or some example setups beyond their marketing diagrams online... Anycase.... I guess we have to write support :D

robromani

I also am surprised how difficult it is to find this info.

I'm about to use a wired thermostat to add my underfloor heating to the Tado system. The diagram earlier in this thread looks correct for my installation, except I have only one underfloor zone. Hoping it works as intended. I assume I don't have to program the wired thermostat, but just connect the 2 wires from the motorised valve to the switched contacts of the wired thermostat. Anyway easy enough to test with a voltmeter if it switches before I install.

Adzyp

@robromani does your UFH have a wall thermostat currently? If so, its a very simple process of straight swapping that for your tado thermostat - certainly was for me anyway. When you go to setup the tado thermostat for the first time it will ask you what thermostat you are replacing so as long as you know the make/model of the thermostat you currently use for UFH it will guide you through

robromani

It is not that simple because the existing wall thermostat is wireless. So I have to run about 12m of cable through a wall, and under the floor to get to the control centre and the motorised UFH valve. Bought the cable today, hope to get it sorted before Xmas. Tested the Tado and it switches the contacts on and off when I change the temp setting.