Wiring Tado Smart Stat

[james2rw]

Hi everyone, currently pulling my hair out trying to wire a Tado Smart thermostat to a Logic Combo 30 boiler.

I have wired as Tado have suggested: Tado live to boiler live, Tado neutral to boiler neutral, COM and NO to room stat in boiler and removed stat link wire. Boiler is always on, but can hear the relay in the reciever clicking so presume that's working. Have also removed manual timer and installed link wire. When I remove all stat wiring (including link wire in boiler) the boiler is always on, which I don't think is supposed to be the case.

Could anyone propese a solution? Would be greatly appreciated!

 

[CBW]

Nice to see you’ve labelled wires, but still put them in the wrong way doesn’t matter as it’s only a switch. Can you post a photo of the front panel? What exactly do you mean the boiler is always on?

 

[james2rw]

Hi CBW. The wires are labelled incorrectly but wired correctly, if that makes sense . By the boiler is always on, the Tado on or off makes no difference to the boiler, it's always on.

There was a link wire that I removed on the boiler between the 2 terminals furthest left (room stat terminals). If I disconnect all Tado wiring (including original link wire) boiler is still always on. My understanding is that with that link wire removed, the boiler shouldnt be able to call for heat, which makes me wonder if something is not wired right in the boiler.

 

[Johnmdc]

The fan on that boiler continues running for about 5 minutes after the call for heat finishes.
Have you waited for that long?

 

[CBW]

You mentioned a link wire for the timer, have you removed that? Set the mechanical time to off and see if the boiler then goes off. If it does, remake wires, setting the mechanical timer to constant and see if you can then use the Tado to control.

 

[james2rw]

Yes we have removed the link wire for the timer and the boiler does go off when we set the mechanical timer to off. Power seems to be bypassing the stat.

My theory is that I need to move the live coming into the boiler one terminal to the left (into the room stat COM terminal) so power can't bypass the stat.

 

[CBW]

Sounds like a dicky timer. Try using the time/clock position, pushing all the pins in and see if that’ll work when wired to Tado.