Hisense AEH-W41H1: local A/C control with ESPHome
Run a Hisense air conditioner from Home Assistant with no ConnectLife account and no cloud. The
A/C’s AEH-W41H1 Wi-Fi module talks to the unit over an internal RS-485 bus. This project puts
firmware you control on that bus: an ESPHome component, hisense_ac, that presents the unit as a
native climate device.
It runs on three kinds of hardware:
| Hardware | State |
|---|---|
| An ESP32 board with an RS-485 transceiver, in place of the module (recommended) | on live units since 2026-08 |
| The stock module itself, through ESPHome’s LibreTiny platform | one module in an A/C since 2026-10-10. No rollback, and a clip on the flash chip is the only recovery |
| Other ESPHome chips (ESP8266, RP2040) | example configs that compile. Never run |
Start with the User Guide: it compares the three and names the page to read next. Not sure your unit is the right kind? Check compatibility.
The guide
| Page | What it covers |
|---|---|
| User Guide | choose the hardware, then the route to a working unit |
| Hardware and Wiring | the module, the 4-pin port, the RS-485 bus |
| ESP32 Replacement Board | parts, wiring, the pins to avoid, staged bring-up |
| The Stock Module | ESPHome on the original module: state, risks, flash layouts |
| Build Environment | the tools, the secrets file, the first flash by hand |
| Build, Flash and Test | the dev.py wrapper and the bench test without an A/C |
| ESPHome Firmware | board files, adding the node to Home Assistant, updates, releases |
| Everyday Control | modes, fan, swing, Eco, Quiet, Turbo and Sleep, and their limits |
| Entities and Diagnostics | every entity, the bus counters, the log lines |
| Climate Groups | several A/Cs as one thermostat |
| Troubleshooting and FAQ | by symptom |
| Wi-Fi Setup Mode and the Status LED | moving a node to another network, the “77” gesture, safe mode |
| Recovery and Reflash | getting back from a bad flash |
For contributors: Repo Map and Build Pipeline, Testing and QA, Protocol Overview.
Firmware notes
Design notes and hardware reference behind the guide.
- Choosing the hardware: the ESP32 board and the stock module side by side, with measured figures
- The ESPHome firmware: design, and the stock module
- The stock module: how it boots, and recovery
- Component architecture: the layers of the component and what each file holds
- ESP32 board notes · QA strategy · Energy monitoring
- Stock parity gaps: what the vendor firmware does that this one does not
Reverse engineering
The protocol and firmware analysis, for porting this to another Hisense unit or checking the claims:
- RS-485 A/C protocol: framing, checksum, every byte offset
- Stock firmware init and comms: disassembly of the vendor module
- Device-type to capability map: how the A/C advertises its own features
- Open questions: what is not settled, and what would settle each point
- Hardware · The vendor firmware’s Matter interface · Cloud and firewall · The community tables
Retired: the Matter firmware
Until 2026-10-12 the project also shipped two Matter firmwares. Both are retired and live on
under the tag matter-final. What that means for a unit that runs one, and how to move it to
ESPHome: Matter Firmware (Retired).
Source
Code, issues and releases: github.com/AndrewDemsDS/hisense-w41h1. A release carries no firmware image. An image holds its builder’s Wi-Fi credentials and keys, so you build your own.
Not affiliated with Hisense, Realtek or ESPHome. Reverse engineering of hardware you own, for interoperability.