Midea branded AC’s with ESPhome (no cloud)

I just would like to clarify why I sent you the photos I sent you, and I would also like to just make sure my question was understood.

You asked me for the original wifi module that the unit came with:
“what type of dongle does it originally use?
osk-10??”

that’s why I sent you these pictures of the original dongles and not my dongle I made with esphome. I opened the white plastic case, and snapped pics of the original USB “smart wifi” that Mr Cool sells with the units. I have no idea what osk-10 is, so maybe it’s a firmware or OS or a board that some mini splits normally come with?

This is a photo of the module I made with the ESP home firmware that works for my 3rd gen Mr Cool Mini split, but does not work for my 4th gen mini split. (which I was able to make with information here)

It’s alright, if it falls out of the scope here then I guess I don’t know where else to turn, lol. This is where I came to originally flash my 3rd gen. Was able to make the dongle above, and control it with esphome using the midea component.

When you open the mini splits “hood”, there is a board that the USB connects to, which has the same serial number on this piece on my 3rd and 4th gen units. then that board has a wire going to another board, which also has the same serial number on it.

I even swapped them around from my 3rd to my 4th gen. Only thing I can really think of is they did something with a firmware update, which if that’s the case, I was only asking on here as it’s the only place on the entire internet where people are talking about flashing esp home on mini splits and just wanted to see if someone was able to do it.

I am not trying to come across rude, I’m just super frustrated, not anyones fault here. The only reason I spent so much money on these 4th gen’s DIY units is because I was able to successfully pull it off on a 3rd gen, and I thought in my head that there’s no way they woulda done something about this, it’s not that popular of a “hack” that they’d kill it. (I coulda gotten off brand ones installed for cheaper than what I paid for the Mr Cool Units that I had to install myself)

The OSK-102/3/4 are the original Midea dongle’s; they are not using the regular ESP modules.
image
Since your picture shows it uses the ESP-12F, it should be reprogramable (but maybe requires some direct wiring).

It could be something very silly, as I’ve seen some people having contact issues (as the port may look like USB, but it is not; the corners of the socket are cut of and a standard USB may not fit properly/not making proper contact…
image
This is also the reason I prefer to use the header plug instead of the USB :thinking:

You are not rude; no offence take in any way :smiley:

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It definitely is not standard USB just like you said, but it is definitely powering up, reporting back to esphome that the module is up, but inside home assistant, the 4th gen ones do not get any data from the mini split. The third gen one works like a charm. I even tried the new dongles I made for the 4th gen’s on the 3rd gen mini split to see if I messed them up, and sure enough, they work on the 3rd gen just fine. I think Mr Cool definitely either did something with the firmware or something else changed. but the crazy thing is that both the original wifi dongles for the 3rd and 4th gen are pretty identical. I guess it might be time to give up for now :\

or maybe going back to your point of making contacts, maybe the unit is powering up, but possibly another one of the contacts isn’t making good contact?

I could also look into trying to reflash the chip it came with to see if that’s possible like you mentioned as well. That would solve any contact problems

Thanks again for your help!!

What does the log says (on the web interface)
you see both tx and rx ??
It should look something like this:

And another question, what does the 4th gen dongle on the old ac (since you did try the 3rd gen on the new :thinking: )?

ok my friend you are a genius. I think you are onto something and maybe we are very close to figuring this thing out. I looked at the logs and it was only getting TX.

so this is a picture of the board that the USB dongle plugs in to:

This board looks identical on both 3rd and 4th gen.

I guess I never tried this combination before. I just took the 3rd gen’s board (from the pic) with my esp dongle in there, and plugged it into the little connector, and it was reporting and controlling my 4th gen beautifully.

Then I plugged the new 4th gen one back in with my 3rd gen esp dongle, and it was also only getting tx.

So I think you’re right, there’s either a contact issue, and maybe I need to either solder directly onto this board from the photo instead of going over usb, or I could just try reflashing the OEM mr cool dongle that has the ESP chip on it, but then I’d have to figure out all of it’s GPIO pins, right?

I’m comparing the two and they look identical to me. Here’s a photo front and back, the one with the USB plugged in is the 3rd gen.

edit: photos have seemed to be cropped, in the front photo, the top one is the 3rd gen


But this is the problematic component for sure.

I love you man! Bypassing it worked! Thank you so much :slight_smile: :slight_smile: :slight_smile: :slight_smile: I was going nuts.

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Great to hear (love it when i am right😁)

you just need to figure out tx/rx pins :wink:

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These are Cielo Breez-i v3 and v4. They are compatible with all Midea units but lack a lot of features (even horizontal swing is not implemented).

Hey, sorry it took me a while but here as requested the photos from the disassembly of the Midea Real Cool 35.
Don’t hesitate to ask questions














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Someone managed to control the led Midea AC without using the IR ccomponent?

@tmsaavedra
No

I figured out the Celcius/Fahrenheit thing in the XYE protocol - code is at the link below. Currently hard coded to airways switch to Celcius, but could easily be configurable.

I apologise if this derails the current focus of this thread, but I purchased the earlier-mentioned SMARTLIGHT SLWF-01pro dongle, shaved off the corners of the USB port, and connected it up. I was able to get Home Assistant to connect to the network and create a dashboard widget for the mini split. However when I go to actually control the unit (change its on/heat/cool state, temperature set point, etc.) then it always goes back to its previous value after one second. I’m out of ideas here and hoping I can get some hints for troubleshooting. Thanks!

Try swapping changing RX and TX. :slight_smile:

Do you know if this esphome component works with midea water to air heat pump (ie. MHC-V30W/D2RN8 )

Also Hyundai HHPM-M30TH looks a lot like ODM Midea to me and it is lot cheaper - how can I be sure it is midea and using XYE protocol?

MD19U-004CW–A系列线控器说明书小册子.pdf Modbus XYE protocol on page 50 of pdf / page 47 of the document

How did you figure out the additional XYE command byte (0xC4) for setting celsius? I’ve never found any documentation on the web with XYE specifics, only Modbus registers.

Just guessing from the gaps in the 0xC? commands known, I suspect there are additional things that can be queried/set through XYE. The big one I’ve been looking for is setting the internal temp (like the follow me) without IR and if the 3F delta for temp can be changed.

I finally got my dongle, but I realized my AC unit’s USB port has a “keyed” edge which prevents the ESP unit from going in. I would have to cut the plastic on either end to make it fit. Did you have to do anything special to yours? Mine is a Senville AC

Yes I had this issue as well, I just used a very small chisel to mimic the notch and kind of forced it in… not an elegant solution but it works.

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The XYE connections are for communication between the (internal) heatpump unit and the remote controller. The H1 and H2 ports are used to connect your ESPhome board. See also my page with info about the connection and a config for the modbus registers: GitHub - Mosibi/Midea-heat-pump-ESPHome