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Low battery causes boiler to run

So this morning at 1am I discovered the boiler was running even though it shouldn't have been. Checked the app and it said the utility was at 12 degrees. Better go and check I think, cause it can only be that low if the window or door is open in which case someone has broken in.

On investigation the valve is showing a low battery. Replace batteries and it tells me the room is 17 degrees and the boiler shuts down.

So a number of issues....

Why did the app think it was 12 degrees? I doubt it ever goes below 17 and it certainly wasn't 12.

Why doesn't the app say lo battery on the display with the temps of each room which is where you are likely to look (appears it may only show this in the device list?)?

Why no warning that batteries were depleted and needed replacing? Surely the app should warn you.

Great system but just not a lot of thought in a lot of places as to what a user might want to see/know where and lack of control over triggering the boiler in such cases.


  • JoeyJoey | Moderator

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  • BudVBudV
    edited February 15

    Sight. What can I say a smart heating system that is dumb. last week the house started to get really hot, and I mean HOT. On investigation found that the battery in one of a rads had competel run out. I asked support - Kristine - for advise - and after waiting ages - and I mean ages - Kristina responded. I had to ask my questions over and over again to get any sort of response - and Kristina took a long, long, long to answer anyting. Poor - very, very poor.

    So, there is some sort of bug so that is why I did not get a low battery warning. And because there was no warning and I did not replace the batteries that rad kept the heating on - and on and on and on. Just dont understand - what if we were awy on holidays for 2 weeks?!

    I think Tado need to update their software to say not only how much enery did we save you - but also how much enery did we cost you due to poor software and poor service - Tado? How much money have you cost me?

  • Not just me then, thanks for confirming what I had happen, the same happens if the hub loses contact with a thermostat.

  • BudVBudV
    edited February 15

    Hey, not a problem. For me I was also very, very annoyed with their online 'chat' support. Oh my giddy aunt - they are appauling

  • I had a battery low email on 2 trvs in the last month replaced one within a couple of days let the other go flat to see result which was it failed open , which I guess is for safety as you don't want trvs closed and boiler trying to heat up
  • That isn't the issue, the issue is the system actually asks for heat and triggers the boiler to run which it will do until the battery is replaced. As you don't know the battery needs replacing you have to notice that the boiler is running when it shouldn't.

    Probably luck yours failed open.

    Given you can't guarantee whether the TRV is open or closed when the battery fails this is exactly why it should not cause the boiler to run. Any TRV with a failed battery or that has been lost from the network should be ignored and you should be alerted in the app.

    I'd have though any modern boiler has a bypass anyway because a TRV can always fail.

    Just had boiler running all afternoon. One thermostat low battery calling for heat but not enough power to open valve. No warning and battery status good in app. Poor deign should never call for heat with low battery. This must be a simple fix as thermostat new it was low.
  • Basically the controller/hub should ignore any thermostat with low battery or that it has lost connection with.

  • Hi guys..I had the same issue today but not quite! I noticed that one of the rooms was freezing.

    Checked the TRV only to find an indicator of low battery. It must have failed on the closed position and the room never called for heat.

    However I received no notifications on the app or any emails telling me about low battery. I have 12 TRVs and 2 thermostats....how am I supposed to know the batteries are dead?
  • Hi all, i faced the same kind of problem. just returned from holidays, battery level of my radiator thermostat was was low, and I noticed it already before leaving, but did not pay attention to it, as we're in the mid of summer and in the mid of a heatwave with outside temperatures up to 36°C; my radiator termostats have been turned off for the last 5 months now.

    however to my great surprise, i noticed that one of my radiators has been running at full power, probably for longer than a week, additionally heating my house during this heatwave.

    i cannot understand at all why a 'smart' radiator thermostat would actually ask for heat whenever the battery level is low (not even empty) or whenever connection with the server is lost. this sounds incredibly stupid to me.

    heating = off whenever battery is empty should be the only logical fallback state of a 'smart' radiator button.

    i'm pretty sure my Tado system has caused more costs & inconvenience in one week than it has saved me in the last couple of years.

    anyone else facing this problem?

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