Analysis

Description:
When using @homebridge-plugins/homebridge-tado (version 8.0.0) to control my Warm Water zone, the plugin passes a raw Fahrenheit value to HomeKit for the Cooling Threshold Temperature characteristic. This exceeds HomeKit’s allowed range (10–35°C) and triggers the following warning:

This plugin generated a warning from the characteristic 'Cooling Threshold Temperature': characteristic was supplied illegal value: number 65 exceeded maximum of 35.

Expected Behavior

The plugin should convert the temperature from Fahrenheit to Celsius before passing it to HomeKit — or use the system’s native Celsius value directly.

Steps To Reproduce

1.	Install @homebridge-plugins/homebridge-tado v8.0.0
2.	Configure and enable a HOT_WATER zone like above
3.	Start Homebridge
4.	Observe the warning in the logs

Logs

Jun 18 18:35:41 Ak-SHS-2 homebridge1392463: @homebridge-plugins/homebridge-tado This plugin generated a warning from the characteristic 'Cooling Threshold Temperature': characteristic was supplied illegal value: number 65 exceeded maximum of 35. See https://homebridge.io/w/JtMGR for more info.

Configuration

{
  "active": true,
  "id": 0,
  "name": "Warmwasser",
  "type": "HOT_WATER",
  "delaySwitch": false,
  "noBattery": false,
  "mode": "CUSTOM",
  "modeTimer": 30,
  "minValue": 30,
  "maxValue": 65,
  "easyMode": false,
  "openWindowSensor": false,
  "openWindowSwitch": false,
  "separateTemperature": false,
  "separateHumidity": false,
  "accTypeBoiler": "FAUCET",
  "boilerTempSupport": true
}

Environment

•	Plugin version: 8.0.0
•	Node.js version: 22.16.0
•	Homebridge version: 1.10.0
•	Raspberry Pi 4 Model B Rev 1.1, Debian GNU/Linux 11 (bullseye)

Process Supervisor

systemd

Additional Context

Add an automatic Fahrenheit → Celsius conversion for any value passed to Cooling Threshold Temperature. Alternatively, expose a config option to force the plugin to use Celsius consistently.

Thank you for looking into this!