Small update to this post after some testing.
MEL Cloud Home and HA status sync up nicely, but do expect a couple of minutes delay in a change done by HA to be picked up by MEL Cloud Home.
One of the units gave a very weird outside temperature (-65 celcius), but that self-corrected after it was running for a while.
Thanks a lot Andrew for this great integration.
Philippe
For me and my air-water, i only have ‘‘Melcloud home’’ displayed on home assistaant integration. Maybe need to waiting a couple of minutes (it installed since already 30 min…). My internal unit is correctly enable in mobile app and i can change parameters… thanks for your help if you have an idea…
Thanks @aremoio for mentioning pymitsubishi/homeassistant-mitsubishi (which is now available in HACS without having to add the repo manually) – early impression is that it works and I have blocked my adapters from reaching the internet (melcloud). I also did buy two of the Protoart adapters and they are very good. The installation does require a considerable amount of dis-assembly of your wall unit, and a few inches of access on the right side are needed.
Which wall unit do you have ?
I have: MSZ-EF50, a MSZ-EF35, and three MSZ-APxx of varying power. The first two are ‘zen’ and the AP are same generation (I think) but more basic white ones.
I have the MSZ-LN series air conditioner. According to ProArt, the Wi-Fi module remains installed on the CN110 port and the ClimateControl is installed on the CN105 port.
The CN105 port is located on the right side of the air conditioner behind the white cover. The exact location can be found in the manual.
So I was hoping this method would also apply to you and that you could use photos to explain how I should proceed.
Just installed one to my parents msz-ln35vg2w, though this one GitHub - echavet/MitsubishiCN105ESPHome: ESPHome firmware inspired by GeoffDavis’s esphome-mitsubishiheatpump, directly integrating the SwiCago library within its codebase. with esp32 s3n16 board.
After the board is configured ant the tail plug is welded to right pins, its was just 3 screws, and the platic cover comes off, then just one screw and the last metal cover comes off. The cn105 connector was clearly marked and free, and the melcloud had it own plug. So then is just plugged the board in and put it all back together. After that the homeassitant found it, and i jus added it to the console.
Thank you, you have saved my day! Almost pulled my hair out on discovering my newly installed system could not integrate with ha. Works nicely!
Hi,
as you have mentioned a MFZ-KT Console I would like to ask whether you are able to control the air outlet at the side of the console (“multi-flow vane”). By the second van control button of the remote controller this is possible, but not by the wifi unit.
I use the Mitsubishi Electric WiFi-Adapter MAC-587IF, and in addition the ProtoART Interface Kit ME_CN105 which I find very well-made and very useful because of its remote thermometer.
In fact, MELCloud as well ProtoArt offer a control called “horizontal…”, but it does not have any effect on the MFZ Console (at least, I don’t discover).
In advance, many thanks for your answer
Yes, that is how mine works. You need to do a fairly significant dis-assembly of the unit, but it stays mounted to the wall of course. Remove vanes, remove plastic shroud around most of the unit. Easy to plug in after that. Be sure to power down system first.
Thanks @andrew-blake, I have been able to connect my MAC-597 using my MELCloud Home account.
I still have to test and play with it, but now I can read the stats and control it from Home Assistant.
Thank you for your work! 
