I've been looking at RMH and RS for a few weeks now and I really like your design and it was something I was thinking of doing. I don't have much room in my house for an RMH but really like the idea of using a RS to produce some heat to supplement my furnace. I have some questions though. Does this system run non stop? I know you have a thermal switch on the fan to shut off when the water gets to be too cold but it looks to be on the HOT side of your heat exchanger. Wouldn't it always be hot enough to have it run unless the fire goes out? How do you regulate temperature in the house? If you stop the blower the water would get super heated... super fast
I'm basically looking for a system I can build that will heat my house primarily and use my furnace as a back up for when it's extra cold or the wood runs out. But so far I'm having a hard time trying to think of a way to regulate the temps inside the house besides how big the fire is in the RS.
ps. why the use of two different tubing sizes in the coil? If the water comes out of the heat exchanger then into your hot water tank does it then return from your hot water tank to the coil? Or is one coil for the heat exchanger and the other for the hot water tank?