New stove old flue recommendations

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New Member
Nov 5, 2023
Need some advice please..

As a kid we had a hearth built in our older brick house. The brick hearth is about 5' x 5' x 2' and had a wood heater with blower that had a side door and an ash pan on the bottom. It was a large heater and would hold I think 24" firewood we cut (several pieces). I don't remember the brand or much more other than the pipe went out the back of the heater into the side of the brick wall where we built an exterior side chimney with a flue pipe in it. The chimney is about 13' tall with a 8" flue. The right angle flue started about 3' off the ground inside the chimney so the actual flue is about 10'.

The house is about 2000 sq-ft with several bedrooms in back of the house (other end). I just remember at full fire that heater would heat pretty much the entire length of the house and run you out of the room it was in due to the heat. I am looking at adding a wood stove back to heat as much of the house and interior rooms as possible. (I know side rooms may take fans of some sort to move the heat). Will these modern heaters work with a right angle flue? I only see top pipe stuff. I don't know about all these 'cat' heaters as well; all I see is numerous reviews on how they are problematic if not setup and fired up perfectly. I was looking for heater with a large firebox that works with a right angle flue. I have looked at the Green Mountain 80, King 40, and a Lopi large cast iron heaters. Any ideas or recommendations would be appreciated.
Thank you for your time..
There are some rear-vented stoves still made, but the short chimney will be a problem. Rear-venting slows down the draft a bit due to the horizontal run but the short, exterior chimney is the real issue. This was not as much of an issue with old stove because they were just a box with fire in it with little between the fire and the chimney. Modern stoves have designs that slow down the fire and inject air under a baffle to turbulate the wood gases and burn them much more completely. That results in a hotter fire, a cleaner burn, and less wood consumed. A different design might use a catalyst to clean up and burn the smoke. Some hybrid stoves like the GreenMountains use both technologies. All need stronger draft to accomplish this. The GM stoves in particular need a stronger draft. The chimney would need 3-5' additional height to draft well for a modern stove. This is particularly true in mild climate areas as the difference between the indoor and outdoor temps is what creates the draft. Woodstock sells rear-vented side loading stoves that may work. Some are side loaders.

While the chimney height is being raised I recommend cementing closed the thimble at 3' and putting in a new one at say 6ft. This will allow a top vent stove to go in. There are some good choices that are less fussy about draft than others.

The 2ft deep hearth will need to be extended. A front-loading stove needs 16" of hearth in front of the door. The extension can be at floor level and might be as simple as a sheet of metal for an ember-protection-only stove.
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