hondaracer2oo4
ArboristSite Operative
Seeing as I have a Hardy OWB and the stack temperature is pretty high, wasting alot of heat warming the outdoors I was thinking about a water coil in the stack that would act much like a sidearm heat exchanger using natural thermosyphon to move the water through the coil. You would simply drill a hole at the bottom and top of the stack where the coil would come out to head to and from the boiler. The coil would run up the walls of the chimney extracting the heat that is going out. It would work much like those portable hot water pressure washers that basically are just a barrel with a coil that goes up with an oil burner at the bottom. You would run each end of the coil back to the boiler. What do you guys think? Anyone thought or seen something like this? It would be pretty easy to make up a prototype to see how well it worked. The only thing that I can see being an issue is the creosote which would get all over the coil and be difficult, if not impossible to clean off. I get very little cresote myself and any that I get is not sticky and is easy to brush off. Just thought it would be a simple yet effective means to extract more heat from the unit. Let me know what you guys think!