Unilux HVAC (Universe) thermostat – cloud API reverse engineering

Hi everyone,

I’m trying to integrate a Unilux HVAC / Universe Wi-Fi thermostat (used in many condos) into Home Assistant.
I’ve only found this old reddit about it, but unfortunately, no one commented about it: https://www.reddit.com/r/homeassistant/comments/1h2cv4g/smart_thermostat_options/

  • it has some useful pictures of the wiring.

I’ve already confirmed that:

  • There is no local API, BACnet, or Modbus exposed
  • The mobile app works via Unilux cloud, and there is an official Amazon Alexa skill, so a cloud API definitely exists

Hardware details:

  • Fan coil units: Unilux DSC-350 / DSC-ERV-600
  • Thermostat: Unilux HVAC / Universe touch thermostat

Goal:

  • Reverse-engineer the **mobile app / cloud API - https://thermostat.uniluxvfc.com (read temperature, set setpoint, change mode/fan if possible)
  • Build either a custom HA integration or REST-based climate entity