SWAP THE MANUFACTURER'S WIFI DONGLE FOR AN ESP8266 AND THE APPLIANCE RUNS ON YOUR NETWORK
The app talks to the company's servers, not to your appliance—swap the wifi module for an ESP8266 and it speaks MQTT on your own network instead.
by Hypfer
HomeAutomation
- difficulty
- ●●○○○
- time
- an evening
- license
- Apache-2.0
- repo
- repo ACTIVE185 stars
●●○○○ · an evening · Apache-2.0 · 185 stars · repo ACTIVE
WHAT YOU’LL NEED
- Electronic parts — full list with part numbers in the repo BOM
- Dev board / microcontroller — runs the project firmware
Partner
COMPAREE VERDICT
This is what the open-source smart home was supposed to be: you unplug the appliance, pull the manufacturer's wifi module from its header, plug in an ESP8266 you flashed with the project's firmware, and the dehumidifier or humidifier afterwards speaks MQTT on your own network and integrates directly with Home Assistant. No account, no servers that might shut down, no route through someone else's cloud. The swap itself is straightforward—solder a connector to match the appliance's header, flash the ESP, plug it in—and both READMEs include pinout diagrams and configuration examples. The hard constraint is the supported model list: the dehumidifier project covers the Midea MAD22S1WWT, Comfee MDDF-16DEN7-WF and MDDF-20DEN7-WF, Inventor Eva II PRO, and Midea Cube 20/35/50L; the humidifier project covers the Xiaomi Mi Smart Antibacterial Humidifier. If your model is not on that list, this will not work. The one thing most likely to go wrong is buying an appliance assuming it uses the same header when it does not—Midea makes dozens of variants, and the protocol is not universal across the range. If your model is supported, this is a clean evening's work and the payoff is permanent local control.
IN THE REPO
NOT IN THE REPO
- —Firmware, flashing guide, wiring diagrams and Home Assistant config are all present in both repositories.
- —The dehumidifier project covers five specific Midea and Comfee models plus the Midea Cube in three capacities; the humidifier project covers one Xiaomi model.
- —No PCB—the board is a standard ESP8266 dev module you buy, the connector is a common JST-XH or similar depending on model.
- —Both projects are Apache-2.0, allowing commercial use.
- —The dehumidifier README includes an explicit safety warning for R290 propane units—the refrigeration circuit must never be opened.
- —No video walkthrough is linked; the README photos and pinout diagrams are the documentation.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Partner · KickstarterBluHub reads and burns Blu-ray/DVD/CD, adds USB-C, USB-A, SD/TF and 10 Gbps data — plug and play, grand-piano finish.
Gallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Check the supported model list in the README—if your appliance is not listed, stop here (The protocol is not universal across Midea's range; an unlisted model will not work.)
- 2.Flash the firmware to an ESP8266 board using the flashing guide (Standard ESP flashing—the README links to ESPHome-Flasher if you are new to this.)
- 3.Solder the connector to match your appliance's header, following the pinout diagram for your model (The connector type varies by model; the README has photos of the correct pinout.)
- 4.Unplug the appliance, remove the manufacturer's wifi module, plug in the ESP8266(The control header is clearly labelled on most models; do not touch the refrigeration circuit.)
- 5.Configure MQTT and add to Home Assistant using the example configuration (The README includes a complete Home Assistant YAML example.)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
- Humidifier project (Xiaomi Mi Smart Antibacterial) github.com
- Valetudo (robot vacuum local control by the same author) github.com
KNOWN ISSUES
- Buying an unlisted Midea or Comfee model assuming the header is the same—it often is not, and there is no way to make an unsupported model work without reverse-engineering the protocol yourself.
- Skipping the supported device check and discovering after opening the appliance that the header pinout does not match the diagram.
- Confusing the dehumidifier and humidifier projects—they are separate repositories with different firmware and different supported models.
- Attempting to use this on a non-wifi appliance or one with a different control module (some Midea units use a completely different system).
- Opening an R290 propane unit without reading the safety warning—the refrigeration circuit must never be drilled or opened, though this project does not touch it.
- Assuming MQTT will work without configuration—you need a working MQTT broker on your network first, and the ESP needs the broker IP and credentials.
Will this work on my Midea dehumidifier?
Only if it is one of the listed models: MAD22S1WWT, Comfee MDDF-16DEN7-WF, MDDF-20DEN7-WF, Inventor Eva II PRO, or Midea Cube 20/35/50L. Other Midea units may use a different protocol or header pinout.
Do I need to run Home Assistant?
No—the appliance speaks MQTT after the swap, so any MQTT-capable system will work. The README includes a Home Assistant example because that is the most common use case.
Can I still use the appliance's physical buttons?
Yes—the ESP replaces only the wifi module, the rest of the control board is untouched.
What is the R290 propane warning about?
Some units use R290 propane as refrigerant instead of traditional refrigerants. The sealed refrigeration circuit must never be opened or drilled because a leak near ignition sources is a fire and explosion risk. This project only touches the low-voltage control header, nowhere near the refrigerant, but the appliance must be unplugged before you open it.
Is there a PCB to order?
No—you buy a standard ESP8266 dev board and solder a connector to it. The connector type depends on your appliance model; the README has the pinout.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
Five specific Midea and Comfee models are supported, plus the Midea Cube in three capacities—and the protocol is not universal across the range. If your model is on the list, what pushed you to swap the module rather than just unplugging the wifi?
Hypfer
Hypfer is the developer behind Valetudo, the open-source project that removes the cloud from robot vacuums and gives them local MQTT control. These dehumidifier and humidifier projects apply the same approach to a different category of appliance—pull the manufacturer's wifi module, plug in an ESP8266, and the device speaks to your own network instead of the company's servers.
Keep building — related projects
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DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
- Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
CompareeTEAM15d ago
Practical notes from our verification: both repositories are active and by the same author as Valetudo, the Apache-2.0 licence allows commercial use, and the supported model list is explicit—if your appliance is not named, this will not work. The dehumidifier README includes a clear R290 propane safety warning (the refrigeration circuit must never be opened), but the swap itself only touches the low-voltage control header. No PCB to order—you solder a connector to a standard ESP8266 board following the pinout diagram for your model. The single biggest trap is assuming an unlisted Midea unit will work; the protocol varies across the range and there is no fallback.