Universal Air Conditioning Controller - ESP32-S3

This universal air conditioning controller based on an ESP32-S3 is designed to replace the Wi-Fi dongle of most air conditioners. The controller can be programmed via the USB-C connection and used with, for example, Home Assistant via ESPHome or MQTT. Examples are available for various brands (see below).

The hardware on the controller converts the 3.3V signals from the ESP32-S3 microcontroller into 5V signals (which most air conditioners work with (do verify this of course)) via a bi-directional level converter. A total of 3 GPIO pins of the ESP32-S3 are available, which means that signal interfaces such as UART and SPI are supported. In addition, there is a step-down (buck) converter on the controller to also handle higher supply voltages (some air conditioning models from Mitsubishi and Daikin, among others, offer a higher voltage than 5V).

To connect the controller to an air conditioner, it offers 3 options:

1. The JST-GH connector. This connector is the standard connector on modern Haier air conditioners.
2. A USB-A connector hat needs to be soldered (this is not included). Various air conditioner brands such as (older) models from Haier, Midea, Electrolux, Comfee, Qlima, Electrolux, etc. use this connector. This pinout is generally universal, but always verify this with your own air conditioner.
3. Loose wires that need to be soldered to the controller yourself.

Finally, the controller also offers the option to solder an IR LED onto the module (this is not included). This way you can also send the same signals from the air conditioner's remote control.

From V1.4 onwards, the module features two solder bridges, which have the following functions:

• SB1: Connects an additional pull-up resistor to GPIO 34 (RX/MISO). Some Mitsubishi air conditioners have a built-in pull-down resistor that pulls the signal voltage down too far. The pull-up resistor compensates for this.
• SB2: Connects VIN directly to 5V. This solder bridge will almost never need to be used. Only in very exceptional cases where the supply voltage is 5V, the extra voltage drop caused by the built-in buck converter might result in the signal voltage no longer being high enough. In that case, the solder bridge can be connected to bypass the buck converter and prevent the voltage drop.

Tested by us:

• ESPHome Haier (tested with a modern Haier air conditioner via the JST-GH connector, see the tab "Downloads" for an example)
• ESPHome Daikin (via custom DIY cable, or the existing cable must be modified)
• ESPHome Toshiba (via custom DIY cable)

Tested by others:

• ESPHome Mitsubishi SPI (hberntsen) recommended for the software for a stable operation. The following page offers a tutorial for the hardware connection: MHI hardware aansluiting (page recommends a DuPont cable, however a JST-XH kabel should also fit in the CNS connector . Note: Cable colors do not match)
  Note: Users report that the module does not always work properly with the following models: SRF25ZS-W and possibly other similar models. Update: V1.3+ should fix this by connecting the solder bridge.
  Tested with: 
  • SRF25ZS-W (with SB1 solder bridge)
  • SRK20ZS-WF
  • SRK25ZS-W
  • SRK35ZS-WF
  • SRK50ZSX-W
  • SRK60ZSX-WF
• ESPHome Mitsubishi SPI (Astute4185) tested with:
  • ZSX-35W
  • ZSX-25W
• ESPHome Mitsubishi UART tested with:
  • MLZ-KP25VG (see the tab "Downloads" for an example)
  • SEZ-M25DA (see the tab "Downloads" for an example)
• ESPHome Panasonic
• ESPHome Hayward Pool Heater or MQTT Hayward Pool Heater tested with:
  • PC1000
  • PC1001

Not tested:

• ESPHome Midea (and Electrolux, Qlima, Comfee, etc.)

Did you get it working with your air conditioner but is it not listed here? Let us know which model you have, how it is connected and we will add it to this page!

Note: Use of this controller is entirely at your own risk. Always check and verify the pinout and signal voltage of the air conditioner (this must be 5V) to prevent damage. We test the electrical part of the controller, but cannot guarantee that it will work with your air conditioner.

Note: To program the module for the first time, it must be put into programming mode. Connect the module to the computer, hold down the boot button, and briefly press the reset button. Then release the boot button.

Check the tab "Downloads" for more information and/or downloads.