Do I need to buy anything to enable opentherm on this boiler?

user1

eli5 please. Just purchased an eu thermostat from the tado website. Have the ideal logic combi c30 boiler.

Will the eu thermostat come with everything I need or do I need to buy any additional hardware, Ive attached my wiring on my boiler

Thanks in advance

johnnyp78

You have everything you need. Make sure you make it clear you want to install with Opentherm when you start installing it and you’ll get customised instructions.

johnnyp78

Just to add that it looks like your Opentherm wiring isn’t connected yet. You’ll need to remove the connector in the white box at the top and connect it to the Opentherm wiring to the right of it.

user1

Thank you, would I be able to do this myself with little to no electrical knowledge (making sure power is always off)?

When you say connect the wiring would I need any additional hardware or will it be in the box or “plug and play”

(I’ve wired in a nest e thermostat before using their instructions)

Thank you

johnnyp78

You need to join two connectors, anyone can do it. They clip together.

user1

https://community.tado.com/en-gb/discussion/comment/71562#Comment_71562

Hi, I've gone through the tado instructions but never got anything about the opentherm wiring. There's an extra cable in my EU tado kit that has black, grey and orange wires. I assume from the instructions these connect to the digital + and - terminals on the receiver but which colour wire goes where and which wires then go to the opentherm block terminals on my boiler please? Thank you

johnnyp78

You can use any wires, the colour isn’t important. + and - on tado go to either Opentherm terminal in the boiler. You’ll also need a power source, assuming you have a wireless receiver? I’m a bit unclear on what Tado device you have. The thermostats are battery powered.

I’m talking about the Opentherm harness inside the boiler being clipped together, nothing to do with tado. You’ll need to look at your boiler manual but it should be fairly obvious. If the wires coming from the Opentherm terminal are loose they’ll need to be connected to the main circuit board, there are two connectors which need to be clipped together.

user1

Thank you. This is what I’ve done so far. I have the eu kit I bought from the tado website https://uk.shop.tado.com/products/wireless-smart-thermostat-starter-kit-v3-eu-version

do I just connect up the loose wires to the + and - digital terminal on the receiver and then into the Opentherm terminals on the boiler?

thank you

johnnyp78

No, you need to connect the Opentherm harness inside the boiler first . You need to look at your boiler manual. Are there two loose connectors? The thing you’ve got in your hand is the timer link plug, which may or may not need to be plugged in. If you do a forum search there are a lot of other people who’ve done this before.

johnnyp78

This might help: https://idealheating.com/uploads/documents/installation-servicing-opentherm-harness-kit.pdf

Look at step 5. There should be two connectors.

user1

https://community.tado.com/en-gb/discussion/comment/74032#Comment_74032

Thank you. I’ve connected them as per the first image in my last post. I disconnected the thing I’m holding then connected the two loose connectors that can be seen behind

ive tried searching but can’t find anything idiot proof on what i need to do next

do i take the blue and brown wire out of the relay terminals and put them into the digital - & + terminals or do i need to connect a separate wire from the -& + terminals to the boiler (like the wire I’ve gotten ready)

johnnyp78

You’re almost there. Keep hold of that timer link plug, you might need it but hopefully you’re good to go. You can use any wire you like to connect the Opentherm terminals (and there’s no polarity either). Probably worth removing the wire from the relay terminals as it’s no longer needed. You need to run wires from the mains in terminal on the boiler to power the wireless receiver too.