Why are the radiators not coming on?

CJs

So, I've tried installing the Tado receiver as per the instructions they gave me. All lights etc are on as they should be. It appears to talk to the boiler, and I can hear it firing up, but the radiators never seem to come on.

Anyone else had this issue?

Boiler is a Worchester CDi Greenstar

johnnyp78

Do you have Tado trvs on the radiators?

CJs

I don't, no. Just the wireless thermostat and the receiver.

johnnyp78

Is it a combi or a system boiler? If it’s a system boiler there might be a stuck hot water valve. If you use the desktop version of the forum you can post photos of the wiring.

CJs

First picture is of the original boiler wiring (Have re-wired back to this and it still works as normal)

Next 2 pictures are of the wiring as instructed by Tado. All lights etc are on as they should be, it does seem to trigger the boiler, but the radiators never get hot.

At a bit of a loss as to what to do next.

It is a combi boiler

johnnyp78

Are you sure you’ve got a combi? You’ve wired the wireless receiver for a system boiler. Do you have a hot water tank?

CJs

Yes, it's definitely a combi boiler. No hot water tank. Followed the only instructions received from Tado. So if this is wrong (or at least for the wrong system), any idea what I need to do to put it right?

johnnyp78

It would be unlikely for Tado to have given you the wrong instructions but not impossible. I’m a little baffled by your boiler’s wiring though. You could try following the instructions for a generic combi install and see if that makes a difference. You’ll need to find out if your boiler connects to relay thermostats potential free or switched live.

https://cdn.brandfolder.io/607DGEMS/as/tqh86npbjjhws5gwkxfncbfh/104172-DIGITAL-WRP01IB01-INSTALLER_MANUAL-TA-UK-00-V2.pdf

CJs

I'm confused by it too. What I can't seem to find anywhere is the receiver for the current wireless thermostats. The house has 2 (One upstairs, one downstairs) Honeywell CM707 thermostats but I can't for the life of me find what they're connected to. There's nothing in or around the boiler, and nothing in any room. My first thoughts were that this is creating some sort of conflict and the Grey and Black wires, that are in the original wiring, were what that receiver was powered by. So disconnecting them should have disabled that, right?

I've tried a few different combinations from both the manual and YouTube to no avail. I've currently disconnected the Tado and put it back to how it was. Been far too much of a headache for one day. I'll email Tado again and see if they can help.

Thanks for all yours.

starconf

The CM707 is a hardwired battery powered thermostat, it is the CM727 that is the wireless version. Could it be they are hard wired to zone valves somewhere in your house? If so it would explain the lack of heating to the radiators if the valves are not opening.