Reclaim flue heat for garage?

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beermann

Feeling the Heat
Jan 16, 2017
318
canada
Just posting this up as a question/concept.

Here is a picture of the wall in my garage. The living room has a wood insert recessed into it.....if I ever rebuild the chimney could I in theory have the design modified so in the garage (picture attached) there is a small opening where I can place a heat exchanger on the flue to blow heat from the flue into the garage?

the theoretical opening could be reinforced and be large enough to I can remove the exchanger when replacing a flue....and I could use a cast iron plate to seal it off when not in use?

The purpose for this would be to intermittently - and freely - heat the garage enough to take a bit of the chill out when I go in there to exercise or work on a project. I currently have a 240v heater that works great and I have plans for a small pellet stove.

Aside from the good idea of a pellet stove Is this heat reclaiming idea bat sht crazy or is it plausible and practical?

Keep in mind this idea would not be a diy handyman special and I assume I'd have to contact insurance, get it certified and all that. I'm just playing with the idea and seeing what you guys think.

Keeping on the same concept of semi-heating the garage with an already existing fireplace, does anyone have ideas?

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Pretty sure you need fire resistant wall between an attached garage and living space. I doubt a hole in the wall would be kosher.
 
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Pretty sure you need fire resistant wall between an attached garage and living space. I doubt a hole in the wall would be kosher.
The more you know :)

I did not look into regulations. Sounds like a pellet stove is the way to go.
 
Stack robbing is usually a bad plan and a quick way to produce creosote in the flue system. If the flue temps drop below around 250 it will happen.
 
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When I first got my wood stove I asked my installer the very same idea that you have now beermann and I thought all I needed would be a pipe or vent or whatever coming off of my stove to heat the rest of the house but it turned out it was not practical for safety reasons and one would need some kind of a full chimney system I guess in order to do this--not quite sure here--but anyway its the beginning of thought for you on how to save money and heat somewhere else with the same heat and it would not hold water or insurance or safety...How I solved my problem to get heat to the rest of my house from my porch was to put in french doors and blow it in if I need that heat elsewhere...But your thinking and getting expert advice as well...My first idea was to have a vent system just like the old days with coal--but my installer man thought I was bat st crazy and you will change your mind on stoves about five or ten times until you decide...enjoyed your question because i pictured me bringing this "great idea" to my installer person and you should have seen his face--so funny...old clancey
 
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Glad to hear I'm not the only one with those kinds of ideas. I can only imagine I would have gotten the same look you did.

The garage is heated but it's with a 240v electric construction heater. I think I'll end up going with either a small wood or pellet stove eventually. For now I'll just keep up with the space heater.
 
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Glad to hear I'm not the only one with those kinds of ideas. I can only imagine I would have gotten the same look you did.

The garage is heated but it's with a 240v electric construction heater. I think I'll end up going with either a small wood or pellet stove eventually. For now I'll just keep up with the space heater.
Wood stoves are generally not allowed in garages by code. Not sure about pellet stoves. Check with the local authority and ask the insurance company first.
 
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Wood stoves are generally not allowed in garages by code. Not sure about pellet stoves. Check with the local authority and ask the insurance company first.
I think it's ok around here. I won't be pulling the trigger on a wood stove anytime soon but you bring up a good point. I could easily drop a bunch of money on something only to figure out I can't just before the install.