Bazsi's Home Automation blog

I had a number of posts about our Buderus heating system in the past, and I had a recent project I wanted to document, both for my future self and for those poor souls who seek solution for this or a similar problem. So my Buderus has a heating circuit that heats a pool and the "need for heat" signal is provided by a simple relay in the pool system: when the relay is closed, that indicates it needs heat. When it's open, heat is not needed. This is basically the same you would get from a "dumb" thermostat, whenever temperature is below the threshold the relay is closed, otherwise it is opened. Furnaces I've encountered in the past always used signals like that. Not with Buderus though, in it a "temperature controlled" zone needs a MEC2 or a BFU installed, both Buderus products for serious $$$. These devices operate on a 1200 baud serial bus and are actually digital devices that connect to the Buderus control system. Buried within the various Heatin