Hi Bart,
I send my commands through HTTP, some of the commands Shelly can use do not seem to work when using MQTT. It might be me at fault here, but initially Shelly had not implemented all commands available through MQTT. So, yes, you are correct!
My intention was to use MQTT, but due to the above, I abandoned it other than for the ongoing Position Control as I felt that would use less power than the HTTP method. (Basically, I have confused myself here!)
1 & 2 - See the 'Shelly TRV Experiments' in the 'dirty' flow that was sent. I build the TRV message by adding the topic messages to the HTTP request.
- Yes, you can see the Profile (1-5) Inject Nodes. I am not using profiles as I control my Boiler through Opentherm Gateway and need to drive the TRV and Boiler in parallel (hence the JSON routine we worked on).
My thought on readings is that a Central Heating System has a large thermal mass (heating, or cooling) and the only thing that really affects this is a door or window opening. However, once the door or window is closed after a brief period, the comfort will return reasonably quickly. If they are open for a long time, then maybe the heating should be switched off - the world has a massive thermal mass and takes a lot of your heating to try to warm it up!
So, if the temperature feedback is updated every five or even ten minutes, does it matter? The answer for that is, as you say, a balance between a reliable value and battery depletion.
I was using Colin's PID loop, which is impressive, but I found that it wasn't really needed with the thermal mass, so have gone to a straight On/Off or Open/Closed control of the valve.
