Sonoff TH16 to control electric underfloor heating

Hi all. I currently have underfloor heating in two rooms in the house (conservatory and garden office). These have ‘dumb’ thermostats with a 7 day programmer built in (something like this - I would like to replace them with Sonoff TH10/TH16 units so the control of the heating can be done via HA.

I know the TH10/TH16 unit is up to the job. All the existing thermostat is doing is checking the temperature according to it’s programme, and turning the AC feed on or off to the electric heat mat below the floor. The issue I have is with the current temperature probe that is in the floor. The current thermostat uses a sensor in the wall mounted unit as well as a sensor/probe in the floor. This gives the thermostat a floor temp reading and a room temp reading. Can this be done with the Sonoff, and if so can I use the existing probe that’s in the floor below the laminate flooring?

My aim is to have the Sonoff connected to the existing probe as well as the separate temp/humidity sensor so and have automation to ensure that the floor probe doesn’t go above a certain temperature (laminate flooring is rated to a maximum temperature, depending on brand) but also take into account the room temperature.

Can all this be done?

Hey, @Nimdy I came across this post from Google, because I’m looking to do the same thing! Did you try it?

I didn’t go down this route in the end. I bought WiFi connected thermostats and flashed them with a firmware that could interface with Home Assistant (