Hybrid RMH

Hello amigos,

I’m planning on building a hybrid RMH using an old cast iron wood stove. However, the exhaust pipe is only 4.5-in wide, and the separation between feeding and chimney is only about a foot long. My intention is to take advantage of the wood stove legs to avoid extreme heat at the bottom of the fire compartment as I am building it on top of wooden floor. I’ll use a layer of perlite at the bottom, and I’ll build the burning chamber with a mix of perlite and refractory concrete, though some refractory bricks will be part of it too.

In short, this will be a 6”:12”:24” J tube, 4.5” wide. Do you think this could work?  I could make it deeper but definitely not wider, as I am limited by the length of the stove, though I guess I could build the feeding chamber outside of the stove (over that frontal terrace).

Thanks a lot!
Pablo

Hi Pablo, and welcome to permies. How would you build and insulate the heat riser in this scenario? What is your design idea for mass storage and exhaust routing?

Hi Pablo,

Welcome to Permies.

Thanks Phil and John,

For the heat riser, I’m planning on using perlite with refractive cement (10:1).