Wood stove heat exchanger, pretty hot
I want to report some news about the integration of a wood stove heat exchanger into my brother’s shop, WerkHaus (see the project here), that I designed and built.
Yep, my brother has finally finished off the heating system with the help of Norm Walters, a radiant heating tech. Its kind of exciting because its the final product of a giant experiment started about 4 years ago. The above image gives and idea of the initial concept on how heating and air circulation would work in Werkhaus.
Originally we started with radiant heat tubing in the concrete slab and Phil used a wood stove up until this fall to heat the building using the fan systems to move heat around the building. This really was lacking though because Phil has to work on cars while on a dolly on the slab, which is really kind of cold down at that level. So, he knew that getting the slab up and running as the heat source would be the ultimate solution.
Phil is on a budget, so a typical on the wall, on demand propane condensing boiler was out of the question, at least for now. Originally Phil and I came up with an idea…What if the wood stove came with a heat exchange manifold? Would this do the trick and provide enough heat to run the slab? Well the answer is yes, but it isn’t quite that simple. Norm Walters filled Phil in on the possible scenario that might make it all work. What it comes down to is you need a tank to store the heat and this tank it was decided needed to be well insulated and preferably do some heating, too. So a couple of years ago, Phil purchased this unit.
Then he had Norm hook up his wood stove, which came with a very simple heat exchange coil by using a typical manifold and pump system like this…. Well to make along story short, he got this hooked up to the slab with a typical manifold system and ran it straight off the wood stove, but guess what? It just wasn’t enough of a heat coil on the stove to make it work or run warm enough. So, he resorted to running off the electric hot water heater, and guess what? His electric bill went nuts. So, Norm found a copper coil from some old refrigerator unit and installed it on the top of Phil’s wood stove to increase the heat capturing capability of the stove and water tank. I am making this sound all quite simple but in reality, it took some fiddling and some pumps, and gauges, and sensors, thermostats, and electric meters to make it all work, along with some rather confusing diagrams…I can’t figure it out too much, but what I do know is that Phil is quite happy with the fact that he is running his concrete slab with the wood stove and looks to save some electricity this winter. He sounds kind of excited about it and I would have to say that makes me happy. With some work, it is possible to make these systems happen and it does help to have a radiant heat techy on hand like Norm.