Double Sided Firplace - insert or wood stove

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pirates712

New Member
Dec 13, 2020
20
Rochester NY
It's in. I'm waiting until after the fire marshal inspects it tomorrow for the first break in fire.

This stove doesn't have a bypass, and according to the manual the baffle comes out through the top of the stove, which requires disconnecting the liner and removing the smoke outlet.

I didn't insist on a block-off plate. I usually like to do things myself, and I assume if I insisted on the block-off plate that would be reflected in the price.
 

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davo1028

Member
Feb 5, 2019
17
Central OH
Looks good! Hopefully you will have room to work to mount a blockoff plate going in on the sides there. Have you thought about something to cover the info tag on the back? Maybe some stove-painted sheetmetal and a few magnets would take care of it...

Also, the blockoff plates are not complicated to make like someone suggested earlier... take your time and use a cardboard template and you'll be fine. A few clamps and 2x4s to improvise a brake to make the bends works well. With the chimney liner in already, you might want to make one in two separate halves and screw them together once it's in place. It's money and time well spent!
 

Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
2,920
SEPA
It's in. I'm waiting until after the fire marshal inspects it tomorrow for the first break in fire.

This stove doesn't have a bypass, and according to the manual the baffle comes out through the top of the stove, which requires disconnecting the liner and removing the smoke outlet.

I didn't insist on a block-off plate. I usually like to do things myself, and I assume if I insisted on the block-off plate that would be reflected in the price.
Looks nice. Congratulations.

Don't consider the block-off plate optional. Without it, you'll be in the same boat as having an open fireplace, but without a damper, essentially an open skylight in your ceiling open all winter. Well, not exactly because I presume you have a top plate, but close enough to lose a bunch of heat out of the house even when the stove is not running.
 

Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
2,920
SEPA
Yeah, I meant to add another sentence in there about how I'm planning on making a block off plate this spring/summer.
Leaving that opening in your house for two or three (or four) more Rochester winter months?

This isn't a complicated job. It is a pain in the ass if you are not experienced with sheet metal. But very do-able. Particularly your double sided fireplace. Don't even worry about making it one piece. Leave the stove right where it's at and use two pieces of sheet metal that overlap a little in the middle.

I get it, I stuffed a bunch of rock wool above my stove and held it up with some rough cut sheet metal wedged in to keep it up there. I've made two other runs at it, but still don't have the final product.

But I will tell you that even the temporary setup is way better than nothing. There's no way I'd have left it open here for even a week in winter, just venting the heat out of my house 24/7.
 

pirates712

New Member
Dec 13, 2020
20
Rochester NY
They did shove insulation around the liner so there isn't nothing, just not as good as a block off plate. I'm confident it's better than just the steel damper between the firebox and the 13x18 flue open to the outdoors.
 
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Easy Livin’ 3000

Minister of Fire
Dec 23, 2015
2,920
SEPA
They did shove insulation around the liner so there isn't nothing, just not as good as a block off plate. I'm confident it's better than just the steel damper between the firebox and the 13x18 flue open to the outdoors.
That'll do for now, glad to hear it. Do you know what insulation they used?
 

pirates712

New Member
Dec 13, 2020
20
Rochester NY
I did quite a bit of research on the subject after they left yesterday. From what I can tell, it's probably fine as long as I never have a chimney fire. It's also probably fine to not have smoke detectors as long as you never have a house fire.

I think I'll be spending the $25 on some batts of mineral wool before the inspection tomorrow.
 
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davo1028

Member
Feb 5, 2019
17
Central OH
I did quite a bit of research on the subject after they left yesterday. From what I can tell, it's probably fine as long as I never have a chimney fire. It's also probably fine to not have smoke detectors as long as you never have a house fire.

I think I'll be spending the $25 on some batts of mineral wool before the inspection tomorrow.
Yeah, that's the right call. The standard pink stuff doesn't seem to be advertised and fire-retardant, whereas the mineral wool is fire-retardant/non-combustible to 2150F. Good luck with your inspection!
 

pirates712

New Member
Dec 13, 2020
20
Rochester NY
Yesterday I replaced the fiberglass with two layers of r-15 mineral wool, cut to fit snugly, and today the inspection went off without a hitch. Not sure the inspector even had a tape measure with him, he was most interested in the connection between the stove and the liner.

First break-in fire is burning down now. Got the center of the stove top up to 250-275, corners around 200. There is a faint smell, I'd compare it to the smell of the new air fryer we got for Christmas. Definitely noticeable but I don't feel the need to open any windows. Of course, it's 18 degrees outside so not great window opening weather anyway. I'm sure the next two fires will be worse, hoping to get them done tomorrow so we can use the stove for real this weekend.
 

pirates712

New Member
Dec 13, 2020
20
Rochester NY
Some updates:
Completed the second two break-in fires on Friday, one first thing in the morning and the second around 3 or 4pm. Definitely could smell the paint curing, but it wasn't bad enough to need to open windows. I did move our hepa air purifier into the living room though and I think that helped. I didn't get any visible smoke haze in the the air and didn't set off any smoke detectors.

Had the first real fire on Saturday, not much to report other than this is a very effective heater, it got the living room up to 74-75 no problem at all. I put the last load in around 3pm and still had enough coals in the back of the stove for a restart with just kindling around 7am Sunday morning.

Sunday evening I decided to try and get some more heat overnight by loading the stove later, around 6pm. I wanted a good couple hours for things to settle down before I went to bed. I added three splits, one very large on on the left side of the firebox and two small/medium ones. I think I made at least two mistakes - reloading on a very hot bed of coals and leaving the air open too long. The stove top was at 315ish when I reloaded, and I left the air wide open for at least 5 minutes before I started turning down (turns out the manual says turn it to 1/2 after a minute). Long story short, it got very, very hot over the next hour. The center of the stove top probably got up to 725-750, and the front-center got up to 800 :eek:. I did not care for this one bit. I think the difference between the center and front of the stove top was partly because of the flames licking up over the top of the baffle and partly because of the steel lintel 2-3" above the stove top that may have been reflecting some heat. After some panicked googling of information from this forum (hint - site:hearth.com in your search terms will return results from hearth.com only), I got two fans blowing cool air on the stove from the back and used some aluminum foil to block the primary and secondary air inlets. I don't think I blocked all the air, but it was enough to slow things down. That 800f measurement disappeared pretty quickly but it took about an hour and a half before I dared to remove the aluminum foil. At that point the two smaller splits were coaling and the big split was pretty well cooked. By 9:30 it was down around 500, 550 at the hottest.

Some things I've learned:
1.) When the stove has been running all day, the stove is hot and the flue is hot and it drafts pretty hard. I think I should have turned the air down almost immediately.
2.) When reloading, let it catch on half air instead of full air
3.) Have aluminum foil handy, just in case

This morning I had plenty of coals for a restart without kindling, so I raked the coals to the front of the stove and timidly added three small/medium splits. The stove was fairly cool, maybe 150-200. They caught no problem and I turned the air to half after a minute like the manual says. I then slowly turned down the air over the next 15-20 minutes, but the stove was still running pretty cool (around 350-400) after 20 minutes or so so I bumped it up a bit. It seems like when I reload on a relatively cool stove, they only really catch +burn at the front of the stove. They seem to burn cleanly, but I don't get any secondaries (expected based on the low temp). Two hours later it's cruising along at 450-500. When I reload on a hot stove, the splits catch along their whole length and get the secondaries going much easier, and it gets up to 650 no problem even with the air turned down all the way. Of course, I've learned since to turn the air down faster.

What I haven't figured out yet is how to get somewhere in between a fire that's puttering along and a thermonuclear inferno. The secret seems to be some combination of what wood and how much wood is being loaded and the temperature of the stove, and the timing of when and how much to turn down the air depends on those variables in a way that's hard to explain to someone who doesn't already know. It's certainly scary when you get it wrong and there isn't an off button and all you can do is block off the air as best you can and wait.

On a cheerier note, last night's inferno got my living room up to 77-78 and it was still 68 when I woke up this morning. That's my first time waking up on a 17 degree morning and NOT hearing the heat pump.
 

danham

Burning Hunk
Jan 12, 2012
122
Cape Cod, MA
...What I haven't figured out yet is how to get somewhere in between a fire that's puttering along and a thermonuclear inferno. The secret seems to be some combination of what wood and how much wood is being loaded and the temperature of the stove, and the timing of when and how much to turn down the air depends on those variables in a way that's hard to explain to someone who doesn't already know. It's certainly scary when you get it wrong and there isn't an off button and all you can do is block off the air as best you can and wait...
I'm no expert, but here's what I do with my Jotul insert (also in a 2-sided fireplace). Always reload with air wide open, but as soon as things catch (when stove is hot), start cutting air right away. To get to that elusive sweet spot, keep subtracting half of what your previous adjust was and wait a few minutes. That helps avoid an "overshoot" into the puttering zone while also preventing the inferno. Obviously your stove is different, but in case this helps thought I'd pass it along.

-dan
 
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pirates712

New Member
Dec 13, 2020
20
Rochester NY
I added three more splits when it got down to around 400 and since they caught immediately I was able to cut down the air very quickly, within a minute without adversely affecting the flame. I got a bit of secondary combustion towards the rear of the firebox and the temps settled in around 600-650, but slowly crept up over an hour or two to 580 in the corner of the "cook top" and 685 at the hottest spot I could find. It really seems to want to get up near 700. The manual does say 400-700 is optimum, so I guess I shouldn't worry too much about 700. I just don't see how I could put more wood in it and not be way north of 700. Does reloading on a cooler bed of coals affect peak temperature? I guess it should, since less heat at the start would cause less offgasing and thus less secondary combustion. More secondary combustion seems to lead to more offgassing and thus more secondary combustion.

My wood seems very dry, I tested one room temp, freshly spit piece and came up with ~15%mc. I've only tested the one piece though because I do not have a proper splitting axe, just a little hatchet, so big pieces are tough. I bought the wood in the fall of 2019, supposedly seasoned for a year, and the weathering patterns on the wood leave me to believe it was left in a pile for long enough to turn grey, so maybe that's true. It's been fully covered since then with a black canvas cover and gets lots of afternoon sun so it might be extra dry.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,232
NE Ohio
The manual does say 400-700 is optimum, so I guess I shouldn't worry too much about 700.
Even that 800* run wasn't the end of the world...close though... ;)
 
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SpaceBus

Minister of Fire
Nov 18, 2018
5,859
Downeast Maine
Hitting 800df isn't an issue, so long as you refrain from doing this often. Sometimes on very windy and cold nights my stove will reach 800 at the hottest point, but this is very infrequent. You will get used to it.
 

EbS-P

Minister of Fire
Jan 19, 2019
735
SE North Carolina
I hit 890F on the top center, the other night on my F400. Had my blower on high and corners were not above 650. The liner temp 6” above my adapter never got above 700 (my alarm is set at 710 which I have only reached when I forgot to close down air a free reload. Wish I had a way to block the intake. I need to fab up something to allow that. At that temp I think I was starting to see a glow near the top behind the door. Could not tell if it was the baffle or the air deflector or both. 10 more degrees and I was opening the door. Not something I want to make a habit of.
Third winter and I still get surprised!
Evan