Hi everyone,
I’m happy to introduce Vasco/Kermi Ventilation, a new unofficial, community-maintained Homey app for monitoring and controlling Vasco and Kermi D, T and X ventilation units.
The app is now available on the Homey Test channel:
Install Vasco/Kermi Ventilation (Vasco/Kermi Ventilation | Homey)
The initial release has been developed and physically tested with a Vasco X500 (VMD-17RPS01). Other D, T and X models may use the same cloud interface, but they still require verification by their owners.
What you need
-
A Vasco or Kermi ventilation unit already visible and controllable in the official Vasco Climate Control app
-
A powered and online Vasco/Kermi gateway paired with the ventilation unit
-
Credentials for the same Vasco cloud account
-
A Homey Pro with internet access
The gateway connects the ventilation unit to the Vasco cloud. Homey communicates with this cloud service rather than directly with the unit. The official mobile app is required for the initial setup, but it does not need to remain open afterwards.
Current features
-
Low, Medium, High, Auto, Holidays and Guests operating modes
-
Permanent mode changes
-
Changes valid until the next schedule event
-
Timed overrides
-
Fireplace mode with a configurable duration
-
Indoor and outdoor temperature readings
-
Supply and exhaust fan speed
-
Bypass, filter, defrost, fault and connectivity states
-
Support for multiple units on one Vasco account
-
Homey Flow triggers, conditions and actions
This makes it possible to replace or supplement the schedules from the Vasco app with Homey Flows and combine ventilation control with presence, air-quality sensors, windows, heating and other smart-home devices.
How it was created
The vendor does not provide a documented public API for this integration. The app was therefore created by reverse-engineering the communication used by the official Vasco mobile application, based on traffic captured from my own account and ventilation unit.
The Homey app was developed collaboratively with OpenAI Codex. Codex helped analyse the captured API communication, design the integration, implement the Homey SDK application, create automated tests and debug the behaviour against the physical X500 unit.
The project currently has more than 140 automated tests, Homey publication validation and CI checks for incoming pull requests. AI-assisted development does not replace real-device testing, so feedback from owners of other models is especially valuable.
Important limitations
This is a cloud integration. It requires internet access, a working Vasco account and continued compatibility with the undocumented vendor API. Changes made by Vasco may temporarily interrupt the integration.
The project is not affiliated with or endorsed by Vasco, Kermi or Athom.
Testing and contributions
The complete source code is public and available under the MIT licence:
GitHub – homey-vasco-kermi-x (GitHub - shejnowicz/homey-vasco-kermi-x: Community Homey app for Vasco and Kermi X Series ventilation units · GitHub)
You are very welcome to:
-
test the app with other D, T and X units,
-
report compatible models,
-
submit reproducible bug reports,
-
suggest new Flow cards,
-
improve translations or documentation,
-
contribute code through pull requests.
When reporting compatibility, please include the public product model, ventilation-unit software version, Homey version and app version. Please never publish credentials, tokens, private device identifiers, raw account responses or network captures.
I’d be very interested to hear which Vasco or Kermi unit you have and whether the app discovers and controls it correctly.
