Aside from all that....... You mentioned in one of your posts that you don't plan on being in that house very long. If that's the case (4-6 years) you won't realize a return on your investment. You'd be far better off taking that $6,000+ and investing in insulation for the house. If you are determined to install a wood burner you would be far better served by putting a nice stove in the house than an outdoor burner, even if you have to put up a chimney. You'll go through 1/4 of the wood. If you still decide to pull the trigger on a hydronic unit, send me a PM if you get up near Cadillac. I can show you some different kinds of HWH's (hydronic wood heaters) in operation and you can see for yourself what you are getting into. You took a great first step by asking questions here.