Retrofit suggestions

[vanee001]

Hello folks,

We have a 1989 vintage Timberland 'Fireplace Heat Exchanger' model RM36 manufactured by Messer Manufacturing in Windom, MN. It is an attractive install, but I don't believe it was ever intended to supply much of the heat to our home. I would like to change that, and retrofit this unit with something more efficient. The masonry is built around the unit, so I am looking for ideas that don't involve drastic stonework. And, being a corner unit presents it's own challenges. The door frames are attached separately, so they are easily removed, but beyond that I would love any thoughts.

 

[begreen]

That's an interesting setup. First time I have seen it.
There are several threads on 2 sided fireplaces. The common suggestion is to support the corner well and put in a 6" liner and then a regular insert with the side of the fireplace blocked off.