I recently had the joy to adjust a heating system powered by a Ökofen Pellematic pellet boiler. It turned out that the heating control for that system has a small web interface running on a Linux system that allows one to set the different temperature values.
The sources are available here. Several more plugins for the different pumps and switches are already in the works. This needs some more work though to avoid lots of copy and paste.
Sadly enough there's no SSL available in the web interface. I already contacted the vendor about that and about the GPLed parts of their software so there's more to come.
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