Sadly, our heating source is very energy-consuming and not sustainable, as we are heating with oil. Ever so popular and cheap, oil heating has been around since the second world war. However, it's a fossil fuel and therefore not renewable. On top of that, the process of creating heating oil creates tons of CO2 with all the drilling and refining. It's an environmental mess.
I was not able to get access to the heater itself, but I was able to photograph the control unit. I am sorry for the image quality, but it's extremely moisty in there.
Lukas Wyss