Hi Neil @tiger_cook !
If you haven’t seen it, there’s lots in this thread already, albeit scattered.
Firstly, the standard ESPAltherma software works well, and integrates automatically with HA. The instructions are very clear, and work fine, with no actual gotchas I can think of. The only “interesting” part is the selection of items to monitor, to use the My Heatpump app at a minimum you’d need
- Outdoor air temp.(R1T) - this is read by the HP itself, does what it says
- Leaving water temp. before BUH (R1T) - if you have no Backup Heater, this is the one to use for Flow Temp
- Leaving water temp. after BUH (R2T) - if you have a Backup Heater, use this for Flow Temp (currently being validated…)
- Inlet water temp.(R4T) - this is the Flow Return temp
- Flow sensor (l/min) - this is the heating water flow rate, which needs to be converted into kg/hour (x 4200 x 0.0166666667)
Handy options:
- LW setpoint (main) - this is whatever the HP is configured to get the LWT to, usually dependent on Outdoor air temp, useful to see how well HP tracks the requirement
- Target delta T heating - not a part of the MyHeatpump app, but very handy for checking what’s going on if you change it!
I used an M5Stack StickC-Plus, because it’s a handy package with no exposed parts and a nifty LCD screen for logging, and powered it from the X10A 5V pin, as per instructions. I used an extended cable to site the StickC in a waterproof box outside the HP casing, which effectively acted as a Faraday cage and prevented the wireless signal from being received. Your mileage will doubtless vary - @Stephen_Crown doesn’t appear to need that and has it in his HP casing. Having it outside the casing is also handy if you want to reflash it with revised parameter - saves getting the heavy casing off again.
I haven’t linked HA to EmonCMS, using the EmonCMS integration, because I preferred the EmonCMS data series, storage and facilities. A small change in the setup.h file makes it work with EmonCMS directly, providing you have an MQTT broker/server set up as part of a local EmonCMS installation. Again, @Stephen_Crown has done this.
If you go directly from ESPAltherma to EmonCMS, as I did, and you subsequently want to export your data to emoncms.org, then you need to set up a regular export of your data to your account in emoncms.org, say hourly. That is because the usual route for data from OEM emon is
- emon sensor e.g. emonTX4 => emonHub
- emonHub => emonCMS (local), with optional emonCMS (remote at emoncms.org)
Sending inputs directly to emonCMS via MQTT means emonHub is skipped, along with the item-by-item link to emoncms.org. It’s just an easy config change in cron.
Once you’ve got data into emonCMS, setting up the Feeds from the Inputs is pretty easy, and then the standard My Heatpump app (basically a pre-configured Graphs display) can be set up.
Cheers
John