It might be a little extreme, but I bought a Sonoff TH with a temperature sensor, connected it to my heater/AC, re-flashed it with an alternative firmware (ESPurna in my case) and configured a generic thermostat in HA.
Total cost about 12€.
If you need to take the temperature far from the heater, you’ll have to add about 4€ for another sonoff.
gl
Something to think about…
In another thread someone mentioned that there are built in fail safes in commercial thermostats for overheating protection, etc. what is the fail mode of your setup? For example if a connection fails does the sonoff fail on or off. Could you cook a pet that is home alone if the system fails?
The sonoff in itself has no fail safe: if it’s on it stays on until told otherwise (or until powered).
I guess it wouldn’t be difficult to modify the firmware so that in case of lost connection, it turns off, maybe for a thermostat application that could be useful.
In any case, my heater has a builtin thermostat, currently it’s on 26 °C, so no risk to roast a pet 
gl
Phew, that’s a relief!
I’m going for Qubino z-wave thermostats, they have built in protection, and they come with external temperature sensors. There are many different types (on/off thermostat, heating/cooling thermostat, pwm thermostat etc). They fit in the walls and the non-thermostat Qubino modules (like cover controllers, relays and dimmers) also are compatible with the temperature sensors. So combining all that with some Home Assistant Generic Thermostats should be an awesome, safe and reliable setup.
How have these been working out for you overall? I know some people have reported issues with the target temperature being incorrect (Z-Wave Thermostat Problem) and HVAC fans not functioning properly in “auto” mode (meaning one would have to create HA automations to turn on the fan to the appropriate speed when the furnace or AC kick on). I have one laying around, but have not installed it yet due to these issues.
They work pretty well as dumb thermostats that I can change the target temperature of which is all I need them for. I just have baseboard heat no HVAC so I am just using that piece of them so can;t comment on the rest.
One of the three reports an incorrect current temp back to ZWave although it maintains the correct set temperature.
What you mean heater/ac, the current going to your heater?
I have the heater outside, not sure about the distance from router. But have thermostats wires inside the house (but no AC there, unless I bring it)
What could I do?
I think you should check the voltage of the thermostat wires but if you have only two wires I’m afraid then you’d have to bring some power there.
If you’re thinking about a sonoff, to operate on thermostat wires you’d need some of the 5v/12v models: they can operate as switch on a couple of wires without implicating them into the power supply…
gl
which model?
something like this: https://www.itead.cc/smart-home/inching-self-locking-wifi-wireless-switch.html
Take into account that re-flashing them would require some soldering and a serial/usb interface: not a super easy task the first time you do it, and that they require an external 5v OR 12v (choose your model appropriately) power supply.
On the bright side, I have 4 of those in my house and they work pretty well with HA once re-flashed…
nice product. WHich enclosure are you using?
No enclosure, they’re in the walls 
I would like to see the Qubino thermostat in action, but they don’t have videos inEnglish for me to watch.
https://www.youtube.com/results?search_query=Qubino+thermostat
Anyway, I would go with Radio Thermostat. It’s not pretty-looking as Nest as I’d like it to be.
However, as a Z-Wave thermostat, once you have a Z-Stick controller, it’ll get the job done. If you go Wi-Fi, for me I would create a VLAN, add a new SSID, assign a VLAN tag to the access point with SSID, and deny that particular VLAN Internet access. I can do the same for Nest thermostat if Google’s Nest team allows local control, but just go with a Radio Thermostat instead.
My policy for home automation within my network is data should never leave my home network unless absolutely necessary. I don’t want my home automation data to reside in the cloud.
Hello, I’m a HA newbie.
I´ve just bought a Floureon HY03WE-4 Smart Wi-Fi LCD Touch Screen Electric Heating Thermostat that works quite well with the dedicated app.
I installed the generic thermostat in Home Assistant but cannot communicate with the thermostat in any direction.
Any comments more than welcome.
Thanks
I have a sonoff basic with tasmota firmware but fail to configure it as dry contacts(relay function) I need to connect or disconnect the two heater control wires together. Any ideas ?
Hello fbl
Did you find the sloution for the communication of your Floureon.
By
Hi. I’m still working with the dedicated app as I cannot make a connection with HA
Hi fbl,
I was looking through AliExpress thes days and there are several vendor offering exactly the same product you are using but all under a different brand name. I started to google these one of the others but so far wasn’t able to figure out the true underlying producer.
But could you maybe provide me with the name of the dedicated app you are using to control your thermostat? And whether that uses an Internet server or somehow connects directly to your local device?
Andreas
Hi all,
I am planning to buy one Touch Screen Thermostat hardware (Any brands) into Home Assistant, as per below:
Then I want to control Aircond temperature via this Touch Screen Thermostat, and updates status to HA.
However, I could not find any custom component that could integrate this hardware into HA.
What should I do to integrate this into HA?
My Thread Link: How to integrate Touch Screen Thermostat into Home Assistant?
Thanks.