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Why does my Worcester Greenplus HE 35 Combi boiler keep firing up? - Problem with TRV's?

Hi all, just wondered if anyone had any ideas on how to solve this. Apologies this is quite lengthy and I am not a pro (obviously)!

I have a Worcester Greenplus HE 35 Combi boiler. I connected the wireless control to it using the instructions. Then I set up the bridge, paired the thermostat and 4 Tado smart thermostatic valves. The smart valves are all in upstairs bedrooms. The thermostat is downstairs. There are 4 radiators downstairs which have non smart thermostatic valves.

After I installed the wireless control I could not get it to fire up the boiler. Apparently it was connected to the bridge, thermostat and smart valves but just would not respond. I ensured to set the boiler time and date correctly as well as set the heating dial on the actual boiler to constant on and E setting as suggested by Worcester boiler manual.

After spending ages disconnecting and reconnecting I did some searching online and found that someone had tried wiring the controller in an alternative way. Essentially, I excluded the black wire, then connected the other wires to a connector inside the boiler to connections 1,2 and 4 (rather than Ns (blue),Ls and Lr as advised). I then put a wire to bridge Ls and Lr. This actually worked in that the boiler now seems to recognise and respond to the Tado smart valves.

The problem is, that when the Wireless thermostat downstairs tells the boiler to fire up, it does so, but then will just stay on. The downstairs radiators (which dont have smart valves) get really hot, then the boiler continues to supply them with heat even once the room temperature is higher than the desired temp set on the wireless thermostat. Also, when a Tado smart valve upstairs comes on, this causes the downstairs radiators to all become hot, despite the downstairs Wireless thermostat being off. I did have the non smart valves set to level 5, but now have put them onto frost mode. This has stopped the boiler from firing up, but I am not sure what will happen when the wireless thermostat actually wants them to turn on later.

Has anyone got any ideas what I am doing wrong? Grateful for any suggestions.


Best Answer

  • GrayDav4276GrayDav4276 ✭✭✭
    Answer ✓
    Hi @TadoBH,

    In my opinion it is never a good idea to improvise and alter the Tado Installation instructions...... Don't get me wrong, sometimes they do need to be slightly changed.....but it's best to do this in conjunction with Tado Support, who have much more experience with Tado Installation Instructions, than we do. It is very common for users to misinterpret what Tado is saying.....I know I did !! However, initially, I thought that I knew better.....I was wrong.

    I recommend that you check that you have followed the instructions correctly, and then contact Tado Support to get your Installation completed and (hopefully) working properly.
    Good luck 🤞


  • Thanks GrayDav,

    Yeah totally agree. I have checked and rechecked a few times and have done what I was supposed to, but maybe there is something. Ill contact Tado Support to see what they suggest.


  • TadoBH, your system seems to be working as expected because you only have one central heating zone/loop so if any smart device calls for heat the hot water goes through all the pipes and then the device connected to the radiator decides if heat is allowed to enter the radiator.
  • Thanks wbjohn, yes that makes sense.

    I spent some time last night and this morning and this is what happened. When I turned off all of my Tado smart thermostats and wireless themostats, the boiler was still firing up and sending heat to the non smart radiators. I can only assume that the boiler is essentially on constant but isnt under control of the Tado system. I therefore turned it off last night to avoid the boiler being on all night.

    This morning I wondered if maybe the Wifi connection wasnt allowing the Tado smart valves or wireless device to talk to the wired controller, but I tested the Wifi in that area and its fine. I also turned on the smart thermostats and then the wireless thermostat and both of them cause the heating light on the wired controller to turn on. That tells me the wifi and Tado demand is all working as it should, but the boiler was still not actually responding to the demand from the control. The boiler was essentially just working on constant mode independent of what the Tado wanted it to do.

    Therefore, I disconnected the Tado wired control from the boiler, then reconnected it exactly as per the Tado instructions (like I did initially). The wired controller still responds to the smart valves and smart thermostat as previously and the heating demand light turns on to tell the boiler to heat, but the boiler does not respond to the command. The boiler still works and heats up when I run the hot water tap (which is obviously separate to the central heating as its a combi boiler) so I know I havent wrecked the boiler. I just cant get the boiler to respond to commands from the wired Tado controller.

    Grateful for any suggestions.

  • When I refer to 'wired control' I am referring to the 'wireless receiver' i.e. the Tado thing you wire into the boiler, that is controlled by wireless temperature sensor. The issue is that the boiler does not seem to respond to the command to heat, when the 'wireless receiver' asks it to.

  • So just to update anyone reading this. I contacted Tado and they were really helpful. I have heard some bad reviews before I bought the kit, but to be fair I could not fault the help I got. They communicated with me by email yesterday within 1 hour, then configured something their end this morning. I then tried to re-install as I did the first time, this evening and everything now works fine.

    Learning point for others - If you install the Tado wireless receiver as per the instructions and it doesnt work, dont spend hours stressing about it and re-wiring things. Just email Tado as you may have done everything correctly but Tado may need to activate something their end.

    Hope this is useful for others.

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