It all started innocently enough. Collect some warmth from the sun and circulate it in the floor. On my trips to look for property, I would occasionally catch up with my old friend Bob, a well-known instigator of trouble. Over dinner, I would update him on my progress; one day I mentioned my idea of collecting thermal solar. This led, of course, to trouble. Or, anyway, an overall system design beyond what I imagined at that point. He insisted that I needed storage for my heat; OK, clearly you collect the heat when it is light and need when it is dark. The Big Warm Thing idea was born. So, now that I have collectors and storage, I may as well also go with a wood-fired boiler that will fill the BWT with cheap heat and hot water in gloomy December and frigid January.
When the dust settled, I purchased 3 16-tube arrays of Seido-5 thermal collectors, found a heat-storage tank of 822 gallons from STSS complete with heat exchangers as specified for my system, and purchased a Tarm Solo 30 wood-gasification boiler. Then I came up with a very simple balance and control system, and hooked it all together. Happily, it seems to work pretty much as I had expected. Even in mid-winter, I only need to fire the boiler at most once a day, for about 4 hours. Usually I can skip two or three days a week and just live off the tank and the sun!
The Tarm and my Solar System control components
The "Wall of Wonder"
The storage tank (AKA, The BWT), installed and filled
What's inside the tank?