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Official Description

Display temperature and status of heat pump, heating and hot water of heat pumps controlled by the Alpha-InnoTec Luxtronik 2.0 controller.

This is an OSS alternative to the controller-provided Java applet, which does not work on mobile devices. You must be connected to the same network as the controller (so for remote access you may use a VPN connection into your home network).

You can currently only display values, not change settings.

Notice:
The purchase price is to protect against uninformed use ("Schutzgebühr").
The source code is freely available on GitHub (see the Website button).