anyone done something with the idea ?

This idea is nothing new. I have been involved with several projects over the years .The first one was back in the early 80's.We used a wood burning fireplace and extracted heat from it to supplement heating the domestic hot water. On the flip side , we have used a heat exchanger and a fan to space heat a home using a boiler. The heat exchanger was built into the fireplace.

I also did something like what acwizard did. But,didn't use a fan though!

I am looking for any input from people who have made fireplce heat exchangers, I am on my 4th edition & feel I have done a fairly decent job, Im looking for all ideas. w photos if possible Ill share what I have done. I made the hearth out of 1" pipe & it heats my boiler water to 100-120 '  [email protected]