Midea VRF Air Conditioner - How to integrate with HA

Hardware
1

[I am creating this topic to ask from everyone else who has similar system and could help understanding the system and integrate it with HA]

We recently installed a Midea VRF (Variable Refrigerant Flow) air conditioner (model is MDV-V200WN1), which includes one outdoor unit (ODU) and several indoor units (IDUs). Additionally, we added a Wi-Fi wall controller (WDC3-120T), connected to one of the indoor units. The indoor units (IDUs) are linked to each other in a daisy chain configuration (wifi controller is connected to IDU1, IDU1 is connected to IDU2, IDU2 is connected to IDU3 and so on; See 2nd figure below).

I successfully added the Wi-Fi controller to the SmartHome app (I think formerly known as MSmartHome / MSmartLife), and it works fine-ish.

However, I dislike relying on online solutions, and I haven’t been able to connect it to my Home Assistant.
Any advice would be greatly appreciated. I’ve attached some photos for reference.

I raised a question in media-ac-lan and no help there. In fact, I scanned the wifi controller’s ports and it looks like it’s not exposing the port that midea-ac-lan is expecting.
I Also looked at Midea-branded-ACs thread, and I don’t think it could directly help this system.
I will add more of my findings later on.

Hopefully this topic could attract more people to find a proper solution.

Here are some photos:

Wifi Controller:
wdc3-120t

Wifi Controller Wiring:

midea-wiring
midea-wiring1470Ă—926 107 KB

(Note that L1 is connected to the wall controller. We don’t have a 2nd wall controller, so L2 is not used. L3 is connected from first indoor unit (IDU) to 2nd IDU, and 2nd to third and so on.)

IDU and ODU example:

midea-vrf
midea-vrf929Ă—598 233 KB

SmartHome app:

midea-mshome
midea-mshome578Ă—954 154 KB

2

X1X2 seem is home bus standard, like the P1P2 bus from Daikin, from their docs it include both power and data, the voltage between them is 18V. You can ask in opensource project P1P2MQTT.

1 Like
3

Yes thanks. It’s some sort of modulation on 18vdc. I’ll check that out. :+1:

4

Same issue, all my IDUs with individual WDC-86T works as expected in Midea SmartHome app, but still looking for solutions to integrate HA

6

Hello Friend!
Did you found a solution?

not a best solution, but WDC-XX wall panels can act as IR receiver.
I’m still looking for full bidirectional integration

7

Yeah the wall controller has ir receiver, however it will work globally. It means if I point the remote to the wall controller, it will turn on “all units” which is not what I want. In fact I disabled the ir on the wall controller.

At the moment I am sniffing RS485 bus on M1M2. It’s very busy and I’m yet to reverse engineer it.

8

Has someone got any success

9

Have you looked at this product?

SMARTLIGHT SLWF-01pro

You can get it for about $13 US I think.

10

There is no such usb ready port on the IDUs. In fact, as far as I understood, the IDUs are not supposed to be indivodually connected to the internet (through a wifi dongle, such as the hacky one that you mentioened). I did look at the IR board and couldn’t see any port that could hint a tx/rx capabilty. I’m sure there are many smart people who can eventually find a way to help me.

11

The wifi is for your system [e.g. Home Assistant] to communicate with it. It is not connected to any cloud service. For non-USB inputs there are people that show how to connect to this device or something you can make yourself that has basically the same ports. I have also seen messages about swapping the RX/TX ports. I am leaving this thread. Good luck other people.