Pete Acker

Thanks Roy--that would definitely be the plan.

After further research, I think my homemade material would be too crumbly, so I'm now planning to spend a bit more and use castable refractory, but keep the same basic design. I realize it won't be as efficient as a true RMH or masonry heater, but I'm hoping for vastly greater efficiency than a wood stove insert, yet still fit on my hearth. And I'm still tossing around ideas for ways to improve the baffle system to remove more heat. I might try channels of firebrick on the inside to attempt to send the exhaust zig-zagging up to the flue...

Thanks for the help thus far.

Thanks John.

OK, so can anyone tell me if the 14:14:1 fire clay:perlite:fire cement material, mixed with shredded fiberglass insulation, will hold up if cast into blocks to make the walls of this heater? For example, the back wall of the heater needs to fit into my fireplace opening, so if the block is 39" x 29", how thick will it need to be to make it structurally sound? 2"? I've never worked with this material before, so I think you all can save me a lot of mistakes! I'm planning on making the J-tube and heat riser 4" thick, as seems to be common, but I assume that is for insulation moreso than structural integrity...

I would appreciate any help with this, thanks!

Pete

Hi All,

I have recently bought a house with a brick fireplace and chimney that was never used, and I want to build a more efficient way to garner some wood heat that will fit on the hearth and in the fireplace. I've researched like crazy on RMH's and masonry heaters, but haven't seen any fireplace adaptations that I like, yet. So, I've been kicking around ideas in my head to design my own, based on a cast J-core and modified from there. Here is what I've come up with (cross section attached, looking straight at the fireplace, with the flue exiting out the back and up the chimney). I'd like to cast the entire structure, probably out of blocks of fireclay/perlite/fire cement. I know you all are the experts, so I've come to you for assistance and comments. First, do you think this concept would work? Would making it out of that material work? How thick should the walls be?

Any other comments would be helpful. I'm not interested in a barrel and typical RMH at this point, and I don't have the masonry expertise or money to afford a proper masonry heater. Thanks in advance for your time,

Pete