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Grant Aerona3 - Home Assistant control via Modbus
Good afternoon all,
I have finally got around to documenting my journey in getting around the woeful controls that the destroyers installers installed when they put in my ASHP. I have used a Waveshare POE ethernet to modbus converter and now have full remote control of my ASHP. The next stage of my project is to build a self hosted AI agent probably using Mistral, N8N and MCP in order to create my own version of a Homely type controller.
If this floats your boat then I commit to thee: https://github.com/Si-GCG/Grant-Aerona3-modbus/tree/main
If you want to join in the fun let me know and I will happily share everything with you as I continue this journey.
Kind Regards
Si
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
Count me in @grantmethestrength
I have a Grant R32 13kw HP. So not the same model, but might be able to help.
Now heating season has finished, I am in the process of installing a
RS232/485 To WiFi/Ethernet Module (Modbus/MQTT Gateway)
From PI hut.
I am also looking at making changes to my buffer / pipe work and installing various flow meters and Emoncms energy meters into the mix.
Just starting out on the HA journey on a PI-4 for testing and a small PC for live workings
Pete
Hi Pete,
I am also looking into getting more sensors as it is bonkers that they don't even install a tank thermometer! I have seen some active discussions on the openenergymonitor forums about AI integrations. I have just got ollama in a docker container and am trying to pull Mistral small 3.1 as I type (top Saturday night!).
I have recently watched
and am going to attempt to get this up and running when I get a chance, I think with various agents we should be able to better analyse the data and then make changes.
Regards Si
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
Not sure if that link is working but it is a video on Cole Medin's channel called
The MCP Integration EVERYONE is Sleeping On (MCP + Custom AI Agents)
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
Yes link works. Starting to work though it, but looks like I need to go back a couple of steps first to understand more
Hi,
Had a look over the information / video and though I can just about follow it and may be able to take a stab at it, I think its a little too much to use AI to deal with automating a HP when a good algorithm / table will do the job and be much simpler to implement.
I notice from Github, that you updates the Chofu one and got a lot more information out of the HP.
Looking at you screen shot, it seems you are able to control the WC, flow temp and stop / start the HP. Which are all the controls you need.
An algorithm should then be able to work out the best options with updates to a table to pass on information between sessions.
This is true, but I about learning about agentic AI and I want to test it out on something lol.
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
Good evening everyone,
I have been busy beavering away and have (hopefully correctly) mapped all the parameters and Modbus registers, there are a few that I am unsure of such as Holding Registers 0,1,97 and 98, Coil Register 0 and Input Registers 21-31. However I have uploaded them to my github repository https://github.com/Si-GCG/Grant-Aerona3-modbus/blob/main/README.md and have attached a spreadsheet with them on. As you will see there are a lot of parameters that can only be set via the controller but there is still plenty to play with. I have added a lovelace template that I have used as a dashboard, you would have to configure your own electricity entities fo the cost and energy tracking etc, and a thermistor to get the DHW temperature.
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
Why not use the original manufacturer controller (Chofu) which is hidden away in a cupboard can't it do everything you need. Use as Chofu intended all parameters can be seen I believe pretty easily.
After my internet being off for a few days, home assistant is now banned from any core duties for the house. Heating being a core duty.
What is your end goal and why?
@johnmo I have the Grant CP04 controls which are practically pre-historic, I want to be able to have granular monitoring and control in order to diagnose and get the most out of the system. It is our first time with an ASHP and still only 5 months in so still learning. Basically the system they fitted is oversized so set and forget is not an option. The ultimate goal is to create a system that will learn my unique environment and tune the HP. I am looking at different options such as basic a HA dashboard that we can manually adjust the WC curve rather than grappling with the CP04 controller, then creating automations based on local weather conditions and forecasts and finally something like “Homely” that uses an AI agent to control the system. Yeah I know I could just get a Homely but where is the fun in that!!!
My HA instance is all local and on its own UPS as is my network gear, I also maintain a backup in a VM “just in case” so I can quickly recover if anything happens to the main device. But if all else fails it will fail safe over to the Grant controller.
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
@johnmo
"Why not use the original manufacturer controller (Chofu) which is hidden away in a cupboard"
If you do a search on Gibhub or Internet, someone tried to hack the controller by monitoring the various signals sent back and forth but could not get thier program/hack to match anything. This was done a few years back.
This looks great, really big thank you for this work etc
@uk_pete_2000 Cheers for the support. I am going to start populating the various helpers, automations and scripts I am creating as and when I create them/get them to actually work/work out which ones work for me. Hopefully these might help other people in the same situation.
Ultimately I am not a heating engineer, I am not a software engineer, I am just someone that has been badly let down by their installer looking to make a less than optimal system better.
Kind Regards
Si
——————————————————————————
Grant Aerona3 13kW
13 x 435w + 13x 480w Solar Panels
Sigenergy 10kW Inverter
25kWh Sigenstor battery
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