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Alexandra001
Rank 1
October 5, 2025
Solved

No heating with Ecodan system since thermostat battery died

  • October 5, 2025
  • 6 replies
  • 191 views

Hi guys, 

 

i wonder if anyone could help. The batteries died in my est wireless thermostat for a couple of days a couple weeks ago. Now even tho i put the reauired temp above room temp and there is the little flame on it as the heating is on, it just doesnt turn it on. Anyone has any idea what i could do? I am close to giving up 😀 thank you

    Best answer by Captainheatpump

    Updated on 15/10/25 by Ben_OVO

    It's a pairing issue between the thermostat and the receiver. Go online and get the pairing process. It happens when the batteries are left flat, quite common. 

    Captainheatpump has also provided this handy YouTube link which helps with this issue:

     

    https://www.youtube.com/watch?v=4H9VkBUfsHs . Is this your thermostat ESI? This might explain what you need. “main, th1, time/zone” they sound like menu’s TH1 would be my best guess as thermostat one is always programmed first, then the next one you will only have and option as TH2. 

    6 replies

    C
    Newcomer
    CaptainheatpumpSolved
    Newcomer
    October 5, 2025

    Updated on 15/10/25 by Ben_OVO

    It's a pairing issue between the thermostat and the receiver. Go online and get the pairing process. It happens when the batteries are left flat, quite common. 

    Captainheatpump has also provided this handy YouTube link which helps with this issue:

     

    https://www.youtube.com/watch?v=4H9VkBUfsHs . Is this your thermostat ESI? This might explain what you need. “main, th1, time/zone” they sound like menu’s TH1 would be my best guess as thermostat one is always programmed first, then the next one you will only have and option as TH2. 

    A
    Rank 1
    Alexandra001Author
    Rank 1
    October 5, 2025

    Hi, thank you for the answer 🙂 yes, i repaired it, but it doesnt allocate the wireless controller to room rc, so i cant change it from the main rc.

      C
      Newcomer
      Captainheatpump
      Newcomer
      October 5, 2025

      Sorry, I don't quite understand by Room RC. Have you got multiple remote frequency thermostats in your property?  is it just a case of renaming the zone to suit the room? god, this chat does funny question marks…..

      A
      Rank 1
      Alexandra001Author
      Rank 1
      October 5, 2025

      I have one wireless thermostat and at the remote sensor settings it doesnt show as an option, all i have is “main, th1, time/zone”

        C
        Newcomer
        Captainheatpump
        Newcomer
        October 6, 2025

        https://www.youtube.com/watch?v=4H9VkBUfsHs . Is this your thermostat ESI? This might explain what you need. “main, th1, time/zone” they sound like menu’s TH1 would be my best guess as thermostat one is always programmed first, then the next one you will only have and option as TH2. 

        Ben_OVO
        Community Manager
        Ben_OVO
        Community Manager
        October 6, 2025

        Thanks for your post ​@Alexandra001 and for your great help here ​@Captainheatpump. Welcome both to the Forum, I’ve updated your profiles to display that you have heat pumps.

         

        ​@Alexandra001 if the YouTube video has helped with this.

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