Nice!<p>This references a couple of OpenTherm project, so let's add the usual disclaimer:<p>The OpenTherm protocol is <i>not</i> open.<p>You can only find the spec for v2, they are now drafting v5. Yearly membership is about 3K if I remember correctly (without testing software, just for the spec).<p>There seems to be big difference in what you can do after v2, and it includes power delivery, maybe more fine grained control on heating curves and such (unclear, I don't have the spec)<p>Not all boilers support opentherm (but most should), and those who do don't support all features (but the most basic should always be present).
esphome is by far the best and most useful piece of software I've encountered in a long time!<p>Even for non home automation. Simple web API to turn gpio's on or off, coupled with some relays makes for a great easy yaml configurable industrial automation system
I went with a more passive solution. I have a fairly regular schedule, for full disclosure. I just bought a few wifi sensors and placed upstairs and downstairs and monitor it. I then set a schedule on my thermostat to reasonable values and have my remote sensors set to +/- 2 degrees with a pop up alert if they don't meet the schedule that I programmed which is worth noticing. No wifi thermostats, just ones that will probably last 15-30 years. The older I get more I grow tired of squeezing out that last 5% of value for 90% more effort and I appreciate the old ways, turning off lights when I leave a room. Unplugging things when I'm not using them. The one automated thing I do appreciate though is my security and camera system, those have actually proven valuable over time and well worth the effort to self install.
Have to say with my background individual room control and measurement always seemed the nirvana, but it seems like a lot of heating design is moving away from this to more constant input / constant loss with outside temperature curve adjustment. Take a look at heat geeks.<p>You’ve got quite a complicated system there. Some of the key design parameters are about getting balanced flow (proportional) rather than bang bang controllers so that you optimise the delta flow return and operate the heat source at lowest realistic flow return values for efficiency.
I had no idea people can get degrees with just PID controller. On top of that, people actually just eyeballing the coefficient in practice lol.<p><a href="https://web.archive.org/web/20240415040111/https://s3.filebin.net/filebin/9bc967860a89ac04ff5c558ed02517774a34ee242109b8299219b212e51c3cd3/f99fdf2dcba024f178b2ae357f3c5086fe7ae0f773f205a8ded8716f79f15675?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=7pMj6hGeoKewqmMQILjm%2F20240415%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240415T040110Z&X-Amz-Expires=30&X-Amz-SignedHeaders=host&response-cache-control=max-age%3D30&response-content-disposition=filename%3D%22p_pic.zip%22&response-content-type=application%2Fzip&X-Amz-Signature=bf1490ddef30a21674676dc9992431cde4186ddeae054320440fa6aee64a32ef" rel="nofollow">https://web.archive.org/web/20240415040111/https://s3.filebi...</a>
So at the end of the day -- I understand this is a satisfying project to undertake. Operationally how is it functioning through the winter and how much upkeep is required from you?<p>I've looked at doing something similar for my home system but the LOE + upkeep make me think the reward to work ratio isn't right.<p>That said I also know that I probably can't find anyone to help build the proper system at my house -- so its a situation where if I want it right I need to do it myself :'(
I came into this expecting to see a questionably reliable implementation of a thermostat that could damage equipment or burn the user’s house down.<p>Instead, I found something closer to what I’d do. The boiler has its own thermostat
and control system. If home assistant goes down, everything is still in a safe state.<p>I have home assistant hooked up to a rather dumb “smart” thermostat. It’s just smart enough to be remotely controlled. I’d far rather use that than have a raspberry pi flipping relays.
I was hoping to see some plots of the PID temperature control in action, I'm curious what is the final fluctuation in room temperature with a setup like this.