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The heating system

One of my former projects was the design and practical realization of an automated wood fired heating system. Two key characteristics of the project were the reuse of junkyard bargains and realization of electronic system starting from component level. Budget was kept low.

The system is now warming a house situated on a farm on the Swedish countryside.
 I for sure have never done a project spanning so many different categories of work. In the end I had done manual metal work and welding, plumbing, electrical installation, creation of control- and calculation algorithms, circuit design and programming to name some.

A box on the upper floor of the house with an Atmega328 microprocessor controls the whole heating 

Here is a video summary of the project:

Systems furnace is a Braland 21 from

The control system that is now up and running can among other things monitor 16 different temperatures, control all the systems pumps and do different kind of logging.

Check this PDF if you are interested in further details:

Creation of an automated heating system PDF

Download the PDF and view it offline because Google's online viewer reduces the graphic quality of the document. 

Comments and questions are appreciated. 


  1. Lenny här: hur reglerar man trycket när vattnet blir för varmt i tanken? jag förstod det som att tanken är kopplad till element i huset, är vattnet kopplad till en vattenledning då? för jag antar att man sänker temperaturen genom inflöde av kallt vatten? mvh

    1. Hello Lenny I reply in english as this conversation perhaps would interest English speaking readers :) There are mechanical safety valves installed that open when the pressure goes to high.
      The radiators are connected to a closed system, meaning that the water is just recirculating. However if the water level for some reason goes low or the system needs to be refilled, the system is hooked up to the tap water supply via a manual valve.


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