Received email: Radiator Thermostat needs new batteries - but the app says that it is good?

Today I received an e-mail:

We wanted to let you know that the batteries in your Smart Radiator Thermostat VA35702XXXXX in the room S... are low.

Your thermostat needs two fresh AA alkaline batteries (LR6) .......

But when I look in the App it shows that the battery is "Good"

Which one should i believe? It is only a couple of months ago I changed the batteries.


  • It happened to me as well yesterday. Batteries changed 3 months ago, says "good" in the app.
  • rafm5
    rafm5 | Moderator

    Similar issue here, one of the wall thermostats reported low battery, but nothing in the app. So far no further errors.

  • I think we have a little "glitch" in the tado° "Low Battery Notification" interrogation calculations.......I have also had emails that turned out to be incorrect.

  • I must admit that I previously have had an episode there the APP showed that the battery level was OK - But the thermostat disagreed (showed low battery) - with the result that it could not close the valve. I had 25C in the room and the radiator was hot. The App showed that the themostat was OFF (Frost Protection Mode).

  • Which notification should we follow? Does anyone have a definitive answer before I try changing radiator batteries which are actually a bit hard to get to!

  • OK, so I think perhaps the tado battery monitoring has been updated. I've had alerts for two rooms that come and go but now one room is staying on constantly

    I suspect tado detects low power from the batteries and creates an alert. The batteries then recover a little and the alert goes away. That's gets more frequent as the batteries get weaker until the batteries are constantly giving low output
  • What is the battery status showing in the app?

  • Same here… only 2 months in use, while app is showing ‘good’ on batt status.
  • I think something has changed in the notification software as I had emails regularly when the batteries are low in the wall thermostat and the smart radiator thermostats without any problems and the app has also showed low battery. I've had my system (1 wired thermostat and 9 SRV's) for a few years now.

    Anyway about a month ago I found my conservatory radiator was getting hot with the SRV set to off. I didn't consider it to be a battery issue as I had no notification via email, the app or on the SRV. I removed the batteries, refitted them and everything looked good so I refitted it and it went through the calibration so I thought that'll probably fix it. It didn't so I thought it might be the valve leaking slightly. Then the exact same thing happened to another radiator just yesterday. On removing the SRV the black pin was fully out so I thought surely I've not got another leaking valve! So I removed and refitted the batteries and the back pin didn't move and I got a low battery indication on the SRV. Fitted new batteries and all working again.

    Even though I still had no indication of a low battery in the conservatory SRV I decided to change them anyway, and guess what, it fixed that too. Not really sure what's going on but obviously not enough battery power to move the SRV but I've checked all 4 batteries and they all show good on my battery tester.

    So, what's changed? Is it a software issue or are my SRV's getting tired? Both are VA01's.

  • Same problem here with one of my SRV after being installed about 6 weeks. But the one SRV in question was one that I left off the radiator for 3 weeks due to the valve pin being stuck up until the valve was replaced by an engineer. I can't see how that would make any difference though. Going to wait until the SRV stops working due to battery getting too low. Which I suspect might be a long time hehe.