TN20 insert - not enough heat

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cdcarter82

Member
Sep 30, 2014
45
Magnolia, DE
I have a TN20 insert installed, first winter with it. It’s a nice little stove, but I think it’s just too small. It is inside a masonry fireplace, with a heat form firebox. The heat form was the driving factor for the stove, as the angle for the smoke shelf was the limiting factor from putting a larger stove in. The main floor which I am trying to heat is about 1500 sf, and the fireplace is centrally located. The 2 rooms the are divided by the chimney do have 16’ cathedral ceilings - which I’m sure is stealing a lot of the heat. Note - I have the flue area stuffed with Roxul to create a makeshift block off plate, the angles on the heat form made it difficult to fabricate a plate once stove was in place.

Like I said, I like the stove but I think I need more heat. My wood is dry, but a mix of poplar, cherry, maple, and spruce.

I had a 30NC in a previous house, but the new 32NC would not fit in this fireplace. I had cut the legs down to fit in the previous house, but see the 32 does not have a leg option. I am considering removing the heat form in it’s entirety next year and putting a larger 3+ cu ft stove in its place. I would have to cut the legs down a few inches to get it in there, as I have a limit of about 30” of height. I’ve been looking at the Drolet Austral, but am open to others. Would like to have the capability of loading N/S ideally.

Any ideas on which direction to go? If I put in a larger stove, I am aware that the TV will need to be relocated.

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Thanks, I have ceiling fans to mix up the heat, but on these cold days in the 20s, the stove room only gets up to ~65 degrees
Smaller fans setup in different areas really help. I use a box fan to help throw heat into my dining room thats to the side and behind my fireplace so its naturally difficult to get the heat in there. Box fans arent very appealing setup on the floor but it gets the job done
 
Smaller fans setup in different areas really help. I use a box fan to help throw heat into my dining room thats to the side and behind my fireplace so its naturally difficult to get the heat in there. Box fans arent very appealing setup on the floor but it gets the job done
I did that in my previous house which was a rancher, and the stove was in the basement. Worked well. I found that it was much easier to push the cold air towards the heat, than the other way around.

I’m just saying if I can’t get the stove room hot enough, pushing the air around at this point wouldn’t help. I’ll give it a shot and see if it makes a difference though.

That said, I have noticed a big difference in my electric bill from running the stove. The heat pump is kicking on a lot less which is nice. I’d just rather heat the house primarily on wood rather than the other way around.
 
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Man that fireplace in the middle between two rooms would be the perfect masonry heater.
 
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If you run it fairly hard does the masonry get warm? High ceilings will be hard to heat. I‘ m just starting to learn my new insert. I am learning that I need to light a fire sooner And because its more convective than my stove I don’t ”feel” the heat until everything as warmed up. Different than my stove where I feel the heat with in 15 -30 minute. A real block off plate makes a difference. I tried with out, then with one then with an insulated one. Last is best. Run the inert blower at a higher speed than you think you should. i like burning poplar because it lights fast but it does have a lot of BTUs. I’ll take my yellow long leafy pine before poplar on a cold day.
 
Since it's your first year qith this stove what is your stt temps? On your first and second loads are you running mid way or turning it down for extended burn time..



The heat is probably sitting at the ceilings...tall room.


But if that stove is only 60k I think its too small.
 
Masonry is warm, been running it 24/7 for the last week or more. But I agree, on a cold stove it takes a full load to get everything warmed up, 2nd load starts putting out heat. I’m running the stove at 5-600 degrees at top center. I turn down the air inlet about 80% on reloads. Agree with ceilings, it’s probably 10-15 degrees warmer up in the eves, where I don’t get the benefit. I do run 2 large ceiling fans in reverse to stir up the air, but I imagine it’s only doing so much.
 
It’s rated at 55-60k btu, which I’m tending to think isn’t enough in my case. I think it would be plenty for a more closed in space, but a bit too small for my house.

Austral is rated for 90k. Would still need to modify the legs to get clearance, similar to my old 30NC, but it’s a close fit if I remove the heat form and re-brick the inside.

Any other large stoves in the $1-2k range with looking into?
 
That said, I have noticed a big difference in my electric bill from running the stove. The heat pump is kicking on a lot less which is nice. I’d just rather heat the house primarily on wood rather than the other way around.
So letting the stove take the base load and then using the "auxillary heat" when it gets too cold for the stove to keep up is not acceptable to you? I was just thinking that going to the expense/trouble that it'll take to go from 80%(?) to 100%(?) wood heat might not be worth it?
 
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It’s rated at 55-60k btu, which I’m tending to think isn’t enough in my case. I think it would be plenty for a more closed in space, but a bit too small for my house.

Austral is rated for 90k. Would still need to modify the legs to get clearance, similar to my old 30NC, but it’s a close fit if I remove the heat form and re-brick the inside.

Any other large stoves in the $1-2k range with looking into?
If 2.0 cu ft is not enough moving to 2.5 just isn’t that big of a change. This is what I have it’s bigger but being picky about your firewood. Exact length, square rectangle or triangle splits and high btu wood that’s extra dry would probably get the same results. But you could do that with a bigger stove too.


Not much else I know would fit you budget or space. FYI. Removing legs voids all UL listing and means you have an unlisted appliance that many insurers won’t cover. a mini split for the room might be an option.
 
All things I have considered, and am continuing to think about. I understand that issues with modifying the stove, but it would still meet clearances (Not that it means anything regarding the UL). That said I would be looking at going from a 2 cu ft to a 3+ cu ft stove.

Also agree about the wood. I may give it another season to think about. Will have 6+ cord s&s by end of winter, mix of maple and oak for the future. I’m thinking that better wood will make a difference too.
 
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So letting the stove take the base load and then using the "auxillary heat" when it gets too cold for the stove to keep up is not acceptable to you? I was just thinking that going to the expense/trouble that it'll take to go from 80%(?) to 100%(?) wood heat might not be worth it?
I likely would not see a ROI on a new stove, that’s correct. I’ve thought about it this as well. I also don’t like to sit in front of a stove and still be chilly in the dead of winter 🤷‍♂️.

Maybe better wood will help next season. I also plan on replacing a few windows in the house too, as they are older and I think the r-value isn’t that great.
 
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I likely would not see a ROI on a new stove, that’s correct. I’ve thought about it this as well. I also don’t like to sit in front of a stove and still be chilly in the dead of winter 🤷‍♂️.

Maybe better wood will help next season. I also plan on replacing a few windows in the house too, as they are older and I think the r-value isn’t that great.
Yeah, I get it...and yes, better wood will help! Keep working on bulding up your stash until you are 2-3 years ahead...then you will always have "premium firewood" (and a little cushion if something happens and you can't make wood one year)
As someone who has lived with, and then fixed, uninsulated walls, old windows, and minimal attic insulation, I can tell you that the windows made little difference (they were really old Pella insulated wood framed windows) adding wall insulation helped some, but the big one was adding more insulation to the attic (I only had about 2-3" to start with) that made a noticeable difference for sure!