Daikin Heat Pump ESPAltherma / HomeAssistant installer bundle for emoncms

Hi All

I’ve been reading some great posts and links on here, particularly the ESPAltherma topics. Thanks to @tiger_cook , @John , @Stephen_Crown great how-to there!

I’m a Daikin installer in the French Alps - I chose Daikin as they’ve got a good support network for my clients here, so I can get help / warranty callouts etc.

I was thinking of offering a low cost bundle to my clients which allows them to have their data live, and allow me to help them optimise their installations. Not everone is as into this as me, and so the full heat meter installation might not be for everyone. Clearly if I come across someone who’s really into this then the full external meters are the way, but I’d like to stand out as an installer that will optimise my clients installations as much as possible, and I can’t do that without some data.

My thoughts are as follows, so I thought I’d test my understanding for some feedback:

ESPAltherma - I’d get M5StickCPlus2 (as there seems to be a recent ‘smart40-githib’ fix to the code on github for the yellow v2 and the previous ‘orange’ one is harder to buy). ~€30
This would send data wirelessly as MQTT

Separate Power monitoring as I’ve read on here that the Daikin data is poor at low power, I was thinking of Shelly kit in my heating electrical sub-board. ~€70-150 depending on phases (domestic 3-phase is very common here)
This would send data wirelessly

As a hub, I was thinking that the most economical solution would be an out of the box home assistant e.g. the ‘green’ plug and play. ~€110
This would receive the data over the LAN from the M5StickCPlus2 and the Shelly (which sent it by wifi) and process/send on to emoncms online.

The objective is that this can be a standard and quickly repeatable setup with the minimum of coding/config at my clients homes.

Is there anything else I should consider if looking to do this for the majority of my installations? Thanks

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I think that’s about it, good Wi-Fi connectivity is a must for the M5 as its range is atrocious!

If I would change one thing - I would change the Shelly EM for a Shelly Pro EM, in your case it’s a bit more professional and I believe more accurate.
Home assistant can do a lot more, look into dashboards and in home displays :blush:I use a Fire Tablet, fully kiosk in the background (to dim the screen based on the kitchen PIR) and the Home assistant app


Sounds like a great plan to me. Ideally, you’d skip the local HA instance, because it’s just More Stuff, but unless someone modifies the ESPAltherma code to use HTTP posting to EmonCMS.org, and the Shelly can do something similar, you need the MQTT/HA locally as a bridge.

The HA can be useful if your customers want to do some automation for the Daikin, but that would only work if they have a Daikin Cloud interface via the MMI/WiFi option or similar.

It’s worth checking out aliexpress.com for M5StackC Plus/Plus2, if you were buying a few of them it could be cheaper or more available, although in the grand scheme of things they are ridiculously cheap anyway. I can see the Plus is still on there.

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I’d agree that having to run and maintain an instance of Home Assistant for each customer who takes you up on this offer is perhaps making yourself more work than is necessary.

Personally, I’d suggest going with a Raspberry Pi installed with EmonCMS. It is specifically focussed on the gathering and presentation of the metrics that you are offering to your customers. As such, everything you need is already installed (a MQTT broker to pass data to and the Heat Pump app). This would mean all data was kept within the local network (unless you chose to publish onwards to emoncms.org), which personally I would see as a benefit as a client.

For you as an installer, I can definitely see the marketing benefits of publishing data to heatpumpmonitor.org (obviously with your customer’s agreement), to show how your installs are top-of-the-SCOPs to other potential clients…and as a demonstration of the information they’ll be able to see with the additional monitoring and optimisation package you are offering to them. This would require a subscription for feeds in to EmonCMS.


Yes @mortstar I’d agree, why make things any more complicated than required? The only wrinkle is the minor change in the ESPAltherma setup.h to send individual messages to the “emon/…” topic (“…” can be whatever hardware name you choose e.g. “ASHP”). If you subsequently want to involve emoncms.org, that requires a simple command on the local device to send the data at regular intervals - using MQTT bypasses the usual HTTP POST mechanism!

If you need any assistance setting that up @Phil_E , I’d be happy to advise.

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Thanks All,

As a non HA person I’m not aware of how complex / time consuming HA would be for a ‘fit and forget’ approach, so it’s great advice to not put things in homes that may consume more of my time - heat pumps are complex enough!

In 2013 I first used the openenergymonitor kit, with a raspberry pi initially having soldered all the TX boards myself. What I found was that the pi kept burning out SD cards every few months. My solution was to get a (Nanode RF) alternative for the base station, which didn’t have an SD card, only sending the data recieved wirelessly (I can’t remember how) through to emoncms online. I’d like to think that the past decade’s iterations has dealt with this SD burnout issue (I see that “industrial” SD cards are now supplied), and PI’s are suitable to be left doing their thing without risk of SD card failure.

If HA is a sledgehammer to crack a nut then I’d be open to the raspberry pi option. Unless anything else is able to act as a MQTT-emoncms .org bridge without local storage (which is easy enough to set up). The pi option is a well trodden path though, and I’m not a real software engineer.

Looking at the description of what’s inside the EmonPi aluminium case, I think I’d only need the pi itself, as the other blue board (also called emonpi) is concerned with locally connected sensors, and the 3rd board is the screen. In my case I’d have the ESPAltertherma and the Shelly sending to the pi via MQTT.

A pi 4, SD card, PSU and case is similar in cost to a HA green.

So the shopping list becomes an M5StickCplus2 (and wires for X10 port), the pi setup and a Shelly Pro EM.

The majority of my clients want things online, so I’d consider that as a default option, but subscription is not free.

The NanodeRF had an Ethernet connection so it’s likely that you had a wired connection to the router.

That’s right, I later used the cat5 cable as a draw wire when fibre was installed!

The problem with this approach though its going to be very brittle:

  • customer changes wifi router/password and everything needs to be reconfigured, and there wont be an easy setup step for customer to change the wifi themselves especially for the espaltherma + shelly + maybe emoncms/Pi device.
  • any network IP address range changes will break things (maybe new router etc), DNS may help but local DNS resolution maybe not wonderful to rely on.

I think I would try and aim for wired solution, so POE ESPAltherma device, and Shelly Pro for wired electricity metering with delivery to an internet endpoint (AWS IOT MQTT or EmonCMS instance online). You then still have the problem of routing network cable. Or could maybe look at mobile 4g connectivity.

Could also just go for the EmonHP solution :smile:

Either way its going to add potentially lots of significant costs/overheads for yourself which you need to price in. And maybe Daikin should be providing this remote monitoring for installers anyway (they do for commercial aircon?)

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@meatballs I can see the attraction of wiring, but the ESP32 in the proposed M5StickC [Plus|Plus2] doesn’t do Ethernet, only Wifi. It’s also powered from the X10M serial port socket, so that’s not an issue.

This post Send Shelly data to emoncms explains how to script a Shelly Pro/Gen2+ device to send data to EmonCMS (local or cloud) via HTTP. So that removes one MQTT requirement.

I totally get the maintenance problem for Wifi, in respect of AP/WPA configuration changes, for both Shelly (requires accessing the device, possibly in AP mode if wifi changed) and ESPAltherma (currently requires text edit and recompilation!). Not much you can do about that, unless you’re prepared to write/test ESP32 code - there are libraries that handle web-based WiFi config, but would need integration into existing code.

The bottom line is that it’s complicated, reliability is non-trivial, and that’s probably why solutions are either expensive, or require lots of user input as a substitute for cash!


Thanks @meatballs I am already concerned that my interest in this is taking me away from the job of being an installer of heat pumps, so I completely agree that solutions need to be robust and ‘fit and forget’. Daikin should give us more access out of the box, but their pro platform “Stand By Me” only shows me error messages and a few settings on my client’s installations.

I found a device called WT32-ETH01, which seems to have an ESP32 and ethernet in the same package. POE is less of a concern as the X10 port on the Daikin provides power. I guess I’d program this WT32-Eth01 the same way as the M5StickC with platformio, just making sure I got the right IO pins…?

So the solution could be a 4 port network switch, with the WT32-ETH01 running ESPAltherma, the pi and the Shelly. Pi would do the MQTT data gathering and send on to emoncms. Switch uplink port would go to client’s router so no wifi.
For further client side robustness, I could use a small 4-5 port router like the ER-X and define it’s switch ports IP adresses to be in a more obscure range not normally used on ISP provided routers. Then the pi can have a fixed IP for the ESP and Shelly to send to, that the client’s router can’t mess up.
Or I supply a local wifi AP with my own SSID/PW so client side changes don’t interfere.

I’ve not used AWS, assuming we’re talking about amazon web services. 5 minutes in the help suggests that AWS can recieve MQTT directly, which could be interesting as the pi would not be needed, but the data would go to AWS not emoncms. I’d then need to define what happens in that environment when the data arrives.

Another 5 minutes on google suggests that Shelly has issues getting to AWS via MQTT although it should be possible…

I found this: Support for WT32-ETH01 board by bgcngm · Pull Request #399 · raomin/ESPAltherma · GitHub

seems like the ESPAltherma could be wired via a WT32-ETH01 board. This way the cabling to the heat pump is just Cat5 (shielded better).

Also consider the p1p2serial solution as that may give better install options from MMI rather than in the unit?

Do the emon units have spare serial ports that could be used for the Comms if someone wrote the code?

Good idea! In principle that can also control the HP if you like…

An RPi has loads of ports you could use for serial P1/P2, but you’d have to write the code, I think. However there is GitHub - Arnold-n/P1P2Serial: Monitor and control Daikin/Rotex (hybrid/Altherma) heat pumps via the 2-wire P1/P2 thermostat interface with an ATmega328P, ESP8266, and electronics. The P1P2Serial library and P1P2Monitor program perform low-level bus operation, the P1P2-bridge-esp8266 program interprets data from/to MQTT supporting Home Assistant MQTT discovery. P1P2Serial may also be used for other Japanese Home Bus System based standards: DIII-NET (F1/F2) bus, Mitsubishi M-Net bus, Toshiba TCC-Link, Hitachi H-link, Panasonic/Sanyo SIII-Net, Haier, York, and others. which runs on ESP8266, understands Daikin-ese, and does mqtt etc. Might be worth investigating.

EDIT The P1P2 adapter is a custom built device, using an Atmega (Arduino) chip to handle the P1P2 part in conjunction with an ESP8266 for Wifi. There are earlier versions using straight Arduinos, but it’s already getting more complicated…

I had looked at P1P2 and decided that there was more of an uptake on ESPAltherma on this forum so would get more support with that. I like ESPA’s DHW signal.

It would be great if either ESPAltherma could send direct to emoncms
P1P2 / ESPAltherma could run natively on emoncms’s pi (along with any other manufacturers that have a following where serial comms has been figured out.
However, both of these could take someone with more skills and time than me.

I think for now my next step is to buy a WT32-ETH01 board and see if I can make it send to emoncms .org via a pi.
I’ll buy a Shelly Pro and see if I can make that do the same.
So for a client bundle I’d have a wired switch/router for my 3 devices and a single cat5/6 to their internet box.

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“good Wi-Fi connectivity is a must for the M5 as its range is atrocious!” Hello, I’m a new member of the community. I have a Daikin EDLA09D3V3. I’ve recently installed HomeAssistant and I’ve had a M5StickC+1.1 for a while, but I’ve been struggling with network connectivity. I’m trying to setup monitoring in HA via ESPAltherma. I’ve got everything configured and have data flowing through to HA (see attached image).

However, as soon as I put the lid back on the EDLA09D3V3 it turns into a Faraday cage, immediately cutting off WiFi network connectivity. I see the M5StickC+1.1 only supports 2.4G (which is fine as I don’t need massive throughput but Ideally I’d like the signal to traverse a brick wall). Normally I run a mixed 5GHz/2.4Ghz meshed LAN. However, I’ve tried extending off my router with a spare WiFi router purely on 2.4Ghz. Even when I have a decent signal (-53dBm), putting the lid on kills it immediately.

Here is a photo of the spare router, and the EDLA09D3V3 with the lid open.

Zoom in and you can just about see the bright orange of the M5StickC+1.1

I’ve tried getting longer dupont cables so I can run them from the rear of the EDLA09D3V3 down a conduit into the house nearer a satellite, but this no longer looks practical. What creative solutions have you come up with to get around this to monitor your heat pumps?

Thanks for your help.


My thought was to run a 4 core cable in to the house from the unit itself. Last EDLA I installed had a load of cables for the indoor controls, diverter valve, etc so I’d try that routing, and get to somewhere with better signal.
Join the DuPont cables to that and put the M5 on the other end.
Others on this forum have just extended the M5 to the nearest house wall and put it in a plastic box

Hi @goldendel check out this thread Daikin Altherma, ESPAltherma & Home Assistant with OpenEnergyMonitor - #121 by squarepeg77 there are examples of external enclosures

Thanks very much @Phil_E & @tiger_cook. From looking at the threads there seems to be 2 options for getting around the Faraday cage:

  1. Mounting the M5StickC+1.1 in a waterproof box outside the cage.
  2. Routing a cable down the conduit from the EDLA09D3V3 into the garage.

Option 1 is a neater solution for me, I’ve checked and there is space in the conduit. However as a retrofit, rather than doing this when the EDLA09D3V3 was installed, I run the risk of disconnecting the cables as I attempt to route the cable through.

Option 2: I can’t see any pictures of how people have found an egress point from the PCB to the outside that would be waterproof/not chafe the cable. Neil, how did you do it? Did you need to drill a hole?

With both the solutions you have to transition from the dupont cable (female end connecting to the X10A) to the 4core/CAT5. Am I correct in thinking you have removed the male end from the dupont cable and terminated the copper in a standard terminal block with the 4core/CAT5 connecting the other side? If that is the case, have you also crimped male dupont connections on the other end of the 4core/CAT5 to connect to the M5StickC+1.1 or have you done something else?

see pics below, its not too tricky, no drilling needed, hope is helps?