Heat only works with hot water on?

boesdorf

I had an electrician install my Tado and they swear they have done it correctly, but my central heating will only turn on when my hot water is on. Any idea what needs switched based on the pictures?

They are saying they did it correctly and if it's not working it's an issue with the boiler, not electrical 😕

wateroakley

Hello @boesdorf. A few pointers ...

• EDIT: The symptoms of heating only when hot water is called are symptoms of a faulty mid-position zone valve.
• The wireless receiver photo shows the lights are 'Hot Water' ON and 'Heating' OFF.
• Can you post a picture of the wiring at the Tado wireless receiver?
• Hard to tell from the angle of the photo if the white wire is in 4 or 5? It should be in 4.
• Do you have an electrical meter or electrical screwdriver? When system is calls for heat, the relay should 'click' and the Heating light should come 'ON'. 4 and 9 should then have 240V on the terminals?

boesdorf

Thanks @wateroakley ! Here is a picture on with heating and hot water on. I've never taken the receiver off but guessing that rogue brown wire should have a home?

therealbatfink

Hello,
My system is also like this where hw must be on so as to use the ch, which is correct as it was like this before Tado was installed.
As per your photo of the hw led, my system can use hw independently too.
Yours of course may be different, so the question is did hw and ch work independently before?

boesdorf

Hi @therealbatfink thanks for your reply. Yes, they worked independently before.

lowcarbon

Hi
From what I can see from your boiler junction box terminals 9 & 10 are indeed CH & HW inputs.
Again from what I can see…the red core which I presume has been sleeved with red tape covering an earth ( yellow/green ) core is turning on the HW.
To test…
Use the test button on top of Tado receiver for CH to see if heating comes on and like wise then try HW test button.
Next step you might be comfortable doing…
But I would disconnect receiver ( power down of course) and connect a live to terminal 9 to see if CH comes on.
BTW …I’m electrician
If your not happy doing this, call electrician back,

wateroakley

@boesdorf Hmm. This is wiring problem or a faulty mid-position valve. If a sparky left the brown wire disconnected like yours, with copper showing, I'd be less than impressed.

lowcarbon

Looking at the wires in your images, it does look like an exposed live core in your Tado receiver.

hugbilly

The wiring centre arrangement looks pretty complicated, what was controlling the system before, when it worked? As others have suggested I would begin by operating the CH test button on the receiver, or turning the heating on with the app., and measuring whether there’s an output on the CH NO receiver terminal . . .

royi

If you have a system boiler with a separate water tank then you'll need to contact support and they will change your configuration. I had the same issue over 2 years ago.