Looking for a simple/relatively dumb Wall Thermostat to replace Secure SRT323

Having made the (forced) move for all my remaining devices from Smartthings to HA, I have some remaining issues with my Z-Wave SRT323: The battery levels are incorrect (always report empty) and I have some issues in NodeRed. Given that it’s the only Z-Wave device I have on my network, I’m considering replacing that wall thermostat that has served me well for about 10 years.

I have difficulty finding a Z-Wave or ZigBee replacement. The SRT323 is quite dumb and the only features I really use are: set target temperature remotely and use node-red to trigger automations when someone touches the dial. To be honest: that’s enough as everything else I manage in HA.

The wiring is quite simple as well, see picture below: there is a relay and if the temperature is too low, it switches so it “calls for heat” - again, in my setup that’s more than enough.

Can anyone recommend a suitable replacement which has been tested and works well with HA. Either ZigBee or Z-Wave is fine.


Are you using this as your thermometer also?
In HA you can create “virtual” thermostats with just a temperature sensor and a input boolean.

When that is done you could control this virtual thermostat from a screen, like tablet, NS panel or just a ESP-Home based rotary encoder.
Or if it has to be ZigBee/z-wave something similar. Like the ZigBee rotary knobs.

I have my thermostats on a NS panel in the kitchen with just up/down buttons to control the temperature

I do but I need the relay that switches the heating on which hangs on that wall, in the current location as my partner is not that big on my 3-d printed designs :slight_smile:

For which Z-Wave frequency are you looking (e.g. EU, US …)? I needed a battery-powered relay/thermostat as well and I haven’t been able to find any other than the SRT323 (I went with Netatmo instead, but that’s mostly a cloud solution - there’s Homekit support, but Homekit is pretty limited functionality-wise).

I’m using a McoHome MH7H. It’s Z-wave and seems pretty good.

@mundschenk-at I’m based in the UK so EU frequency. Did you get the SRT323 to work properly, e.g. report battery levels more or less accurately? Mine always says 0% whilst the screen works :slight_smile:

@templeton_nash - that looks nice and I will explore further. I’m not sure my wall has the hole behind the thermostat but besides that, the device looks very nice.

My wall didn’t have quite enough space so the electrician put a small space in between.

I didn’t buy it because I had no Z-Wave experience back then. Instead I got the Netatmo Smart Thermostat.

That’s not battery-powered though.

I had 2 2gig thermostats z-wave with ability to power from a common wire in addition to batteries. I eventually replaced them with ecobee 3 lite. I don’t use all the features and it is cloud based. The ecobees’ have worked perfectly but they do have a delay and updates can be slow. I also used an add-a-wire to get the common wire to the main floor. The ecobees’ are not battery powered.

Here is a link to the add-a-wire:

Thanks for the suggestions!

I use a sonoff mini to replace my old thermostat. I’m able to cover it with just a blank faceplate from B&Q. I stuck a Xiaomi temp and humidity sensor to the faceplate. If you don’t have the depth then buy a junction box to sit on wall