Smart Thermostat Help

Good afternoon.

I bought BHT-002-GCLW thermostat on amazon uk. I have to say that I’m really happy with it even with the headache that doubles the temperature, but is not a difficult fix.

But “my wish” is to have some way to know when it send the signal to the boiler to start heating, and when it stops. As far as I see, you have the hvac heat mode, but this one only has On and Off. Off is fully off, and on, is just waiting to have 1 degree under the target temp to start the boiler, but nothing is showing in the app or in ha when is working or not.

So I don´t know if someone is able to help me or know another thermostat that not that expensive like the big brands.

Thank you