Heat shields reduce heating capacity of stove?

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Thanks!! Nice site ya got here!! I am planning to buy a new woodstove, just trying to research it first. Another question, I have a bilevel house. How practical would it be to locate the stove on the lower level? I would have to run the chimmney up thru a upstairs bedroom, boxing it in, of course.
 
Spook said:
Thanks!! Nice site ya got here!! I am planning to buy a new woodstove, just trying to research it first. Another question, I have a bilevel house. How practical would it be to locate the stove on the lower level? I would have to run the chimmney up thru a upstairs bedroom, boxing it in, of course.

The experts here can give you a more specific answer, but my stove on first floor is near an outside wall, and the pipe runs up to just under the ceiling, then does a right angle through the wall to the outside at the eave, then another right angle and straight up outside from there. The chimney draws fantastic. It's a small stove and doesn't make my 2nd floor bedrooms real warm and cozy, but they're noticeably warmer than they were from the baseboard heat when I was using that (old farmhouse with decent attic insulation but no central heat on 2nd floor)

This is a fantastic site, and the incredibly smart and experienced folks who hang out here can guide you through the whole thing. If you've never heated with wood before, you're going to love it.

By the way, it helps people answer your questions better if you put your general location in your sig. Wood heating issues in Virginia are different from those in the Yukon.
 
Thanks for the info. I thought I had southern Michigan for location. I might run the chimmney like yours. I was concerned that it might not draw very good.
 
Spook said:
Thanks for the info. I thought I had southern Michigan for location. I might run the chimmney like yours. I was concerned that it might not draw very good.

My apologies, spook. You do have it, I was looking at the response post, I guess.

There are a whole bunch of factors that go into setting up a chimney that draws well, way beyond my puny level of expertise, including the height and pitch of your roof and your geographical surroundings. In my case, my chimney guy knew exactly what he was doing and that my chimney would draw extremely well even with the two right angles.

The guys here can give you advice if you post the details, dimensions, etc., of your location and house and what you're planning to do.

My guy did explore running the chimney straight up to the roof, but it would have had to go through a closet I couldn't afford to sacrifice (old houses basically haven't got any!) and he thought, correctly, that he could make me a chimney that would draw well without going straight up through the roof.

You do, though, absolutely need expert consultation so you don't end up spending all that time and money for a less than satisfactory chimney. If you're going to do it yourself, I think this is pretty much the only place to get that level of expert advice.
 
Spook said:
Do heatshields required for close clearance installations reduce the heat availible to the room?

In general no - not to the point where you will notice it. For the most part the add-on shields on wood stoves just reduce the overall radiant heat, meaning that the hot air between the heat shield and the firebox vents into the room anyway. So unless you're buying a stove that's already too small, I doubt you'll notice the difference. I've never heard of heat shields actually increasing heat transfer, but since it will hold a little more heat in the firebox, it could help get the draft going in a shorter amount of time.

One of the bigger drops you could make to the efficiency of your unit is to use double or triple walled stove pipe. The flue acts like a big radiator and has a lot of surface area which depending on your ceiling height/vent config can add up to several times greater surface area than your stove alone. We've all seen people spending so much time researching the most efficient wood stove only to turn around and cap the heat with double walled insulated pipe.
 
On the double wall stove pipe bit. Well, that's one of the best parts about double walled pipe. It keeps the flue gasses hot and promotes good draft and less creosote. If we let all the heat out of our flues like by using one of those heat reclaimers then we would condense all sorts of funk into our chimneys.
 
Webmaster said:
No, I think they may even increase the performance because they get the air circulating quicker.

Despite my inherent fondness for radiant stoves, I'd have to agree.
 
Highbeam said:
On the double wall stove pipe bit. Well, that's one of the best parts about double walled pipe. It keeps the flue gasses hot and promotes good draft and less creosote. If we let all the heat out of our flues like by using one of those heat reclaimers then we would condense all sorts of funk into our chimneys.

With a lot of modern stoves, there simply is not much "funk" to condense. So I doubt single wall, in most cases, will cause a problem. That said, you always have to strike a balance....although EPA tests (I think) use 15 feet of single wall pipe straight up.
 
Webmaster said:
With a lot of modern stoves, there simply is not much "funk" to condense. So I doubt single wall, in most cases, will cause a problem. That said, you always have to strike a balance....although EPA tests (I think) use 15 feet of single wall pipe straight up.

Correct, 15' vertical single wall pipe for EPA certification, although one day I'm sure the testing will catch up so you have to test any offsets you list in the manual too. :coolsmirk:
 
Spook said:
Thanks for the info. I thought I had southern Michigan for location. I might run the chimmney like yours. I was concerned that it might not draw very good.

You'll be better off, if at all possible, to run the pipe straight up from the stove, without any angles. You'll get better draw and it'll be easier to clean too.
Snyde
 
gyrfalcon said:
Spook said:
Thanks!! Nice site ya got here!! I am planning to buy a new woodstove, just trying to research it first. Another question, I have a bilevel house. How practical would it be to locate the stove on the lower level? I would have to run the chimmney up thru a upstairs bedroom, boxing it in, of course.

The experts here can give you a more specific answer, but my stove on first floor is near an outside wall, and the pipe runs up to just under the ceiling, then does a right angle through the wall to the outside at the eave, then another right angle and straight up outside from there. The chimney draws fantastic. It's a small stove and doesn't make my 2nd floor bedrooms real warm and cozy, but they're noticeably warmer than they were from the baseboard heat when I was using that (old farmhouse with decent attic insulation but no central heat on 2nd floor)

This is a fantastic site, and the incredibly smart and experienced folks who hang out here can guide you through the whole thing. If you've never heated with wood before, you're going to love it.

By the way, it helps people answer your questions better if you put your general location in your sig. Wood heating issues in Virginia are different from those in the Yukon.

Gyrfalcon is 100% correct. The long time wood burners and professionals here can provide invaluable info to a newb, such as myself LOL. I did tons of research and asked God only knows how many questions here before pulling the trigger on a PE T6 Alderlea in January of this year. My only regret is that I didn't do it sooner. falcon is right again when he says you'll love heating with wood. There is some physical labor to it. But, the rewards are many.

btw.... thanks again to all who were good enough to answer all those questions for me :coolsmile:
 
Spook said:
boxing it in, of course.
8 feet of 6 inch stovepipe = 12 square feet of of radiating surface area in a room where there is no fire. If you box it in consider a 6 inch by 6 inch vent top and bottom. Convection will do the rest. I've got something similar and the air coming out the top vent is between 120ºF and 250ºF depending on what part of the burn cycle the stove is in.
 
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