Why does 'wired' thermostat require batteries?

VH42

Considering replacing wired thermostat (+ controller) with Tado wired system. Why does Tado 'wired' thermostat require batteries. In the proposed installation, a remote village hall, battery thermostats are a no-no.

If allowed on here, and if Tado DOES need batteries, can anyone recommend a system that doesn't, but still allows remote control via app.

Thank you.

eezytiger

The wired part is for relay switching mains voltage or processing a low voltage digital signal. There is no power supply within the smart wired thermostat (SWT). I've had Tado V3+ for over 3 years and I may have replaced the SWT batteries once in that time period, but no more than that.

If you are only using Tado with the SWT and without Tado SRTs then it could surely be scheduled in with routine maintenance, perhaps annually for preventative reassurance, or wait for the low battery warning and then deal with it within a few days or couple of weeks (maybe).

If you also have Tado SRTs then they will need battery changes more often, so will require routine maintenance either on demand or within a timeframe to ensure that none expire too soon.

Perhaps lithium batteries in the SRT would be a way to extend battery changes in the SWT to a few years rather than one or two.

I can't advise on alternatives. I've only used Tado.

VH42

Thank you eezytiger, that's most helpful. We do not have SRTs so that's not an issue. The reason for not wanting batteries is that they have a habit of disappearing! Other than that, so far Tado is heading our preferred option list.

Treskelion1959

If you are referring to either system (Tado X or Tado V3+), both the Room Sensors and Smart Thermostats are only publicised for use with AAA alkaline batteries … not great for the environment. The only “helpful” note is that Duracell Optima rechargeable batteries are too short! The engineers must have the blueprints for each sensor plus the specification … so how about publicising the dimensions for correct spring tension on connectors, the maximum width to fit compartments and the maximum/minimum mAh for lithium batteries … or is Tado still designing boards that cannot handle the lithium batteries “dropoff” quirk? In 2025?

I can’t be the only person to have a micrometer and/or vernier gauge to follow the engineer’s guidelines?

wateroakley

Hello @VH42 A simple adaptation would be a couple of small drilled holes, top and underneath, with self tapping screws to fix the front panel onto the backplate. It wouldn’t stop the determined battery magician, but would hinder the opportunist amateur. BTW, the wireless temperature sensor batteries have lasted 2.5 to 3 years.