Fujitsu AirConditioner Controller for HomeKit

Flash to an M5Atom, and add your Fujitsu AirConditioner (Heatpump) to your HomeKit home. Should work with most other ESP32 kits as well.

Quick start

• Download the latest release
• Download NodeMCU PyFlasher
• Plug in your M5Atom
• Launch NodeMCU PyFlasher
  • Set your serial port
  • Select the downloaded .bin file as your NodeMCU firmware
  • Select 'Dual I/O (DIO)' as Flash mode
  • Erase flash to 'yes'
• Click 'Flash NodeMCU'

You can either use the built in SoftAP mode to configure the WiFi details and pairing key:

• Hold down the button for 3 seconds until the LED flashes cyan quickly
• Press the button 3 times, the LED should triple-blink
• Hold the button for 3 seconds again to enter AP configuration mode
• Connect to the 'Fujitsu Airconditioner XXXXXX' AP that should now be available and enter your WiFi details and setup code

Or the serial monitor:

• Open Serial Monitor
• Enter 'S ' to define the HomeKit pairing pin (eg 'S 11122333')
• Enter 'W' to enter WiFi connection details

Connect the unit:

• Connect the M5Atom to the AirConditioner via the 3-wire interface (see example circuit) or via the com connector on the indoor unit (will need a logic level converter)
• Power-Cycle your air conditioner.
  • You may need to toggle the dip switch on the Primary controller so that it 'forgets' its setup.

Secondary Mode

By default the controller binds to the indoor unit as a secondary controller. If you do not have an existing wall remote controller, you will need to edit FujiHeatPump initialisation to bind as a primary controller.

QR Code

You can generate a QR code to scan with Home.app by using the QR code generator tool

# python3 gen_qrcode 21 111-22-333 FUJI output.png

Alternatively, you can use an online QR code generator such as the-qrcode-generator.com, just enter the generated setup payload which is printed after you enter your custom pairing pin (eg X-HM://00KUG4GWTFUJI)

Example Circuit

Other ESP Boards

This controller should work fine on other ESP boards, with the following setup:

• GPIO 19 - LIN RX
• GPIO 22 - LIN TX
• GPIO 27 - NeoPixel Compatible LED (SK6812/WS2812C/etc)

Parts Required

• LIN Tranceiver
  • MCP-2025-330 (or similar)
  • http://ww1.microchip.com/downloads/en/DeviceDoc/20002306B.pdf
• 10uF Capacitor
• 10k Resistor
• 12v -> 3.3v (500mA+) voltage regulator
  • https://www.pololu.com/product/2842