Uneven coal bed creates cold spots?

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Dec 30, 2021
6
Maine, USA
I live in Maine. Brand new house built in 2021... Very well insulated and sealed up tight. Our stove is a Hearthstone GM60. Double wall pipe that's 20' with a weather cap. House is 1800 sq ft with the Woody as the sole heat source.

My problem is that when I load the stove up, regardless of how hot or how much wood I put in, I'll get a nice strong flame and coal bed in the front of the stove (roughly the first 6-8") but the back of the stove (last 4-5" or about 1 log's worth) appears to be choked for air and wood largely just smokes and turns to charcoal that slowly very slowly burns away. I get a pretty uneven burn out of the stove and it does not seem right. When the stove was installed the crew said it was missing the metal protector for the upper firebrick deflectors. I was getting absolutely horrible burn results during my first couple uses and it was burning quite erratically. I discovered they (or the factory) had stored that metal bracing piece on the upper air inlet on the back upper part of the stove and I ultimately removed it and placed it in the proper spot while I was waiting for them to order a replacement part. (Very disappointed with the stove installers, they still haven't called me back about getting that installed and it's almost 4 months later). That said due to the way the fire burns so unevenly I'm wondering if something else is amiss or is that normal for this stove. Or maybe even the way I'm placing the logs?

I have poked around some on the forums but have not notice anyone else with this problem.

Firstly, I'm using only Maine grown hardwood. Seasoned for a year to 18 months, however I will admit my tarp was slightly undersized this year so a couple pieces have some moisture to them but I try to let those rest but the stove for a few days to dry out when I find one. Our wood is between 16-18" and I largely can only load them lengthwise into the stove so airflow isn't optimal I get thay. Further, I will usually rake out the hot coal bed to make it nice and even before adding new wood, and I allow new wood to catch before flipping back the cat, but the coals at the back of the stove appear to get choked out regardless of what I do, even if I leave the damper fully open (unless start the burn with it fully open and never shut it down so it's very very hot). Ultimately, 9/10 the back part of the stove is the area that will have coals left during an overnight burn but the majority of the time this area has black coals and is actively smoking and basically producing charcoal. Just moreso looking to see if this is normal for the stove?
 
Where is the stove located in home...does this stove have an ash pan?

If it's oak I would say it's a wood issue. Try splitting wood smaller and test mc and see if it burns better...
 
Welcome to Hearth. Do you have a moisture meter? If not. Get one. First thing to confirm. Your stated seasoning time will not do the job on hardwoods in many locations.
 
I just installed a GM60 last spring so I'm still learning how to use it. It is definitely finicky with wet wood.

I am wondering how much ash you leave in the stove? I notice there's a sweet spot where if you have too little the air doesn't get under the wood but if you have too much (up past the lip) the air doesn't get back there.

Also, since you have to load this stove East West, it's important to keep the wood back from the door a little bit as the primary air inlet is front and center. If you have a split laying against the lip it will burn weird. I also try to create a little path from the inlet to the back through the ashes.
 
Welcome to Hearth. Do you have a moisture meter? If not. Get one. First thing to confirm. Your stated seasoning time will not do the job on hardwoods in many locations.
I don't have a moisture meter, however I know the majority of my wood is dry. With an exception of the occasional piece that I mentioned. Those wet ish pieces I leave next to the stove for several days to dry out as best as I will likely get. I don't have creosote build up at all so my wood is seasoned.
 
I just installed a GM60 last spring so I'm still learning how to use it. It is definitely finicky with wet wood.

I am wondering how much ash you leave in the stove? I notice there's a sweet spot where if you have too little the air doesn't get under the wood but if you have too much (up past the lip) the air doesn't get back there.

Also, since you have to load this stove East West, it's important to keep the wood back from the door a little bit as the primary air inlet is front and center. If you have a split laying against the lip it will burn weird. I also try to create a little path from the inlet to the back through the ashes.
That amount of ash might be the problem I'll try working with that as I think I have too much in there. I'll also incorporate the air channel technique
 
Where is the stove located in home...does this stove have an ash pan?

If it's oak I would say it's a wood issue. Try splitting wood smaller and test mc and see if it burns better...
It's located in the living room adjacent to a door heading into the garage. And it's a mix of maple, oak, birch, cottonwood, and cherry. Most of which were standing dead so I'm not too worried about it being wet. I have no issue starting a fire at all.
 
I think you will find the general consensus here is that hardwood probably needs more than 12 months split and stacked in order to be at proper moisture content.
With that said, I have the same stove, and I do know what you're talking about. if there is a log in the bottom back of mine up against the wall, it is usually the last piece to burn down. I do the same thing as 51221, every time i load the stove i use my little rake tool to just push a couple inches of space in front of the dog house (lower front primary air hole), so that air can get under the load. I actually don't mind having those coals left in the bottom in the back, when i need to reload i just use my rake to roll that charcoaled piece forward a few inches into the middle, it sits there for 3 minutes with the air full open while i go get wood and when i come back it has transformed into a red hot little pile of coals to build the next fire on.
The other thing you might try is two small sleeper pieces. I almost always put at least one piece of kindling running N/S (front to back) underneath the load, and that allows air to flow front to back more readily.
Funny timing, i was just thinking this morning, i'm going to cut some wood this weekend, and i'm going to start cutting it all 11" long. Unfortunately it'll take me 2 years' of drying time before i can report back, but i think loading this stove 100% N/S might be a pretty nice change.
 
I think you will find the general consensus here is that hardwood probably needs more than 12 months split and stacked in order to be at proper moisture content.
With that said, I have the same stove, and I do know what you're talking about. if there is a log in the bottom back of mine up against the wall, it is usually the last piece to burn down. I do the same thing as 51221, every time i load the stove i use my little rake tool to just push a couple inches of space in front of the dog house (lower front primary air hole), so that air can get under the load. I actually don't mind having those coals left in the bottom in the back, when i need to reload i just use my rake to roll that charcoaled piece forward a few inches into the middle, it sits there for 3 minutes with the air full open while i go get wood and when i come back it has transformed into a red hot little pile of coals to build the next fire on.
The other thing you might try is two small sleeper pieces. I almost always put at least one piece of kindling running N/S (front to back) underneath the load, and that allows air to flow front to back more readily.
Funny timing, i was just thinking this morning, i'm going to cut some wood this weekend, and i'm going to start cutting it all 11" long. Unfortunately it'll take me 2 years' of drying time before i can report back, but i think loading this stove 100% N/S might be a pretty nice change.
The very first time I went to load the stove I had this very thought... I then went out and looked at my 6 cords of cut and stacked wood shed and said maybe in a few years I could try that. Guess we think alike bud!
 
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It's located in the living room adjacent to a door heading into the garage. And it's a mix of maple, oak, birch, cottonwood, and cherry. Most of which were standing dead so I'm not too worried about it being wet. I have no issue starting a fire at all.
In one shed I have wood covered for two full years and the oak and large pieces are not ready...it will burn but not as good as the older stuff...

Any wood at bottom of a rack that is outside always gets me too.. the wind hits this with water. So the metal IBC tote bins did not work out for me.

If you don't have ready to burn wood you will chasing any troubleshooting problems...
 
We had a pretty wet "drying" season this year in Maine compared to say last year which was quite dry . . . and while the wood may have been tarped my experience has been that while most species of wood covered for a year or so will burn . . . the longer you give it, the better it gets.

In my first year I burned wood that had been "seasoned" a few months and covered. I also burned a lot of pallet pieces to bring the stove up to temp. I thought I did OK.

The next year I burned wood that had been seasoned for about a year or so and I did much better and I was quite happy . . . until I burned wood in Year 3 which had been seasoned for about two years and then it was a whole other experience.

Your wood may be fine . . . or it may not . . . best way to determine this would be a cheap moisture meter. Take a reading on the face of a fresh split.
 
Agree with jake on the year 3 wood. Wow, I've only ever thought I was burning seasoned, until I stumbled on using the remainders from rotating last year or 2 pile. It burns much hotter/longer, and I'm using fewer splits, definitely my new routine.