Stove can't keep up... wood not burning hot enough

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rwilson

New Member
Sep 18, 2008
59
Northwest Ohio
This is my first year with a wood-burner, and so far it has been great. I have a HearthStone Heritage stove. Yesterday was the coldest day yet, with temps around 5 degrees and a wind-chill of about -25 degrees. We have a new house, 2 years old, but get hit hard by the wind out of the west. Anyways, I was burning wood all day yesterday, and the stove top temp only got to about 400-450. It was mostly around 400 all day. The air-intake was wide-open, burning the wood fairly quickly, but it just could not get hot enough. The room with the stove stayed around 72 all day, but the other rooms in the house (only 1400 sq. ft.) were around 58-60 degrees.

Any ideas what I can do here? I've noticed when I get the stove pass 500, the heat really rolls off of it, but I just couldn't get it that hot yesterday. The wood isn't as seasoned as I'd like it to be, but it's burning clean (glass is very clean and no smoke from chimney). Any ideas are welcomed.

Thanks
 

smokinj

Minister of Fire
Aug 11, 2008
15,980
Anderson, Indiana
rwilson said:
This is my first year with a wood-burner, and so far it has been great. I have a HearthStone Heritage stove. Yesterday was the coldest day yet, with temps around 5 degrees and a wind-chill of about -25 degrees. We have a new house, 2 years old, but get hit hard by the wind out of the west. Anyways, I was burning wood all day yesterday, and the stove top temp only got to about 400-450. It was mostly around 400 all day. The air-intake was wide-open, burning the wood fairly quickly, but it just could not get hot enough. The room with the stove stayed around 72 all day, but the other rooms in the house (only 1400 sq. ft.) were around 58-60 degrees.

Any ideas what I can do here? I've noticed when I get the stove pass 500, the heat really rolls off of it, but I just couldn't get it that hot yesterday. The wood isn't as seasoned as I'd like it to be, but it's burning clean (glass is very clean and no smoke from chimney). Any ideas are welcomed.

Thanks
What kind of wood is it?
 

deadon

New Member
Sep 30, 2008
101
Central Pa
Are you running any fans or blowers?
 

rwilson

New Member
Sep 18, 2008
59
Northwest Ohio
I can't say for sure. It was a dead, standing tree we just took down. It is a hard wood, and given the rest of the species in our woods, I would *guess* Elm.
 

rwilson

New Member
Sep 18, 2008
59
Northwest Ohio
Deadon, we have a ceiling fan in about every room in the house. I tried running all of them on low, running just the one in the stove room on low, and not running any of them. Doesn't seem to make much of a difference. We do not have the blower on the stove... yet!
 

smokinj

Minister of Fire
Aug 11, 2008
15,980
Anderson, Indiana
I would say its just not quite season enough yet!
 

edthedawg

Minister of Fire
Running the primary wide open?? you're pumping all your heat up the chimney. Need to balance it back out - once you get a good roaring fire, then back it down - i leave mine about 1" to 1/2" open. If I leave it running wide, even with the damper i have on the back of it, it burns like crazy but never actually warms the stones.

I also park a box fan on low either next to it or in the next room blowing towards it. mostly open floorplan, and that really circulates the warm air - makes a nice loop. I try to blow it pretty much straight at the side loading door so it moves air across the glass, more or less. The glass gets up to 750+ easily - lots of heat xfer there...
 

deadon

New Member
Sep 30, 2008
101
Central Pa
I have a small box fan in the corner behind my stove moving air to the stove not from it, and my ceiling fan blowing up, I leave the doors open between rooms and the air seems to move well. I tried a blower but the small box window fan seems to work better. You want to move the cold air from the home to the stove not move warm air to the cold areas. Cold air naturally flows to heat. That is how you get a draft in cold weather the cold air is moving, not the heat. All this rambling on, What I am trying to saying is, try to move the air from the cold rooms to the room with the stove, the heat with naturally be displaced with cold air that needs to be heated therefor heating your home. In this cold weather I can maintain 70 in most areas but I do burn more wood.
 

ksting

Member
Sep 21, 2008
74
Central Connecticut
rwilson said:
Deadon, we have a ceiling fan in about every room in the house. I tried running all of them on low, running just the one in the stove room on low, and not running any of them. Doesn't seem to make much of a difference. We do not have the blower on the stove... yet!

Bingo! Get the blower and you'll notice a big difference!
 

savageactor7

Minister of Fire
Jan 25, 2008
3,783
CNY
rwilson if you have a blower on try turning it off and make do with the ceiling fan.

Also when you suspect the fire is under performing rake the coals forward and poke the logs a little...the ash on the logs/coals will actually insulate it from help prevent them from burning up. Oh and don't load the stove all the way when your at home...try 1 or 2 logs at a time, that will help you to burn hotter.

Keep in mind part of the charm of wood heat is that it's NOT even. Having cooler parts of the house is normal, just be thankful we don't have that many real cold days like they do up in Canada.
 

Hogwildz

Minister of Fire
As Ed said, cut down the air intake so you get secondary and she will raise in temp and heat better. You are letting the heat flow right up the stack.
A blower is also a very good suggestion. Once she is heated, you need to distribute that heat.
 

InTheRockies

New Member
Aug 15, 2008
366
Northern US Rockies
rwilson said:
Deadon, we have a ceiling fan in about every room in the house. I tried running all of them on low, running just the one in the stove room on low, and not running any of them. Doesn't seem to make much of a difference. We do not have the blower on the stove... yet!

You need to use a fan on the floor, pointing toward toward the area with the stove, to move cold air into that room and get the warm air moving out--ceiling fan alone won't necessarily do it. The fan doesn't have to be large--this is the one I use.
Honeywell_table_fan2.jpg


That said, remember you stove is a space heater and in abnormally cold weather, other rooms may stay cooler. I'd say it's performance is not unreasonable. We've been stuck in an arctic cold pattern for two weeks now with temps of -24F, -47F with wind chill. Cranking the stove up during the day, I can keep the house at 72F (the den can feel a little cooler, but I can live with it). Overnight burns, it's getting a little chiller than usual, around 64F when I get up, but the night time temps have been very brutal.
 

G-rott

Member
Jan 7, 2006
165
Petoskey Michigan
Ed and Hogwidlz nailed it. Once you get the fire rolling cut back on the primary air. Keep the heat in the stove and get the secondaries going.

In my stove a load of small split and rounds putts off the most heat, large splits give a longer burn.

Garett
 

drdoct

Feeling the Heat
Jan 24, 2008
431
Griffin, GA
smokinj said:
I would say its just not quite season enough yet!

I would say you've got the right answer. Maybe seasoned, but probably not dry. Not dry enough is the answer to probably 95% of the I can't burn hot enough questions.
 

edthedawg

Minister of Fire
we have a 2800+ sq ft Victorian w/ 1200 sq ft "footprint", stove located in the center of the 1st floor. 2nd floor bedrooms were around 60 this weekend with it at 15 to 20*F out, snowing and blowing. 3rd floor / finished attic was about 56. The "cold" part of the attic was actually warmer due to the chimney living in that part! Once the construction is wrapped up on the 2nd floor, i'm gonna likely keep the attic wide open all the time...

Fired up the oil a handful of times this weekend just to take the chill off the kids' bedrooms when they were upstairs. 6 yr old was observed to still run around the house butt nekkid. Turned the heat down after that...

We let it burn down overnight (neither I nor Woodstove Goddess wanted to get up at 5am to reload) and at 7:30am, it was 62 downstairs, about 57 in our bedroom. But even with normal (oil-fired / steam radiators) heating running its regular cycle in all years past, our bedroom is always the coldest room - wouldn't get over 62 in yesterday's conditions. and that's after insulating and new windows... too much exterior wall exposure...

To summarize the very long, rambling story - you need a hot stove, and air in motion. It sounds like you are crippling yourself on both aspects.
 

buckeye

New Member
Apr 4, 2007
83
I'm probably not far from where you are so I have had the same conditions. Like others have said, get the wood charred good for about 10-20 minutes and turn the air down about half. Then leave it there for about 15 minutes and close it almost all the way. Leave it open maybe an 1/8" or so. You should see the secondary tubes blowing flames at that point. That will bring the stove temp. up really well. If your wood is seasoned this stove is definately enough to heat a newer 1800 sq ft home. Our first year I probably wasted as much wood as I got heat out of. You think that leaving the air open and seeing all the flames that it has to be hotter than closing the air and not seeing as many, or the ones you see are dancing above the wood. That was the way I was always thinking, bigger flames = more heat. Not True.

Look at my link below. I heat this mass with mostly the heritage. It was built in 1912, no way to insulate the walls, cheap replacement windows that I have to put plastic over and generally not very well sealed up. The past few days my boiler has been running quite a bit, but, when the temp is above 20, it rarely runs. Maybe during the day when we are at work but not when we are home at all.
 

buckeye

New Member
Apr 4, 2007
83
also, how big of splits or rounds are you burning? I like to use 5-6 3" to 4" rounds I will put on a couple bigger splits when I go to bed, but the smaller splits seem to get the heat up easier.
 

gyrfalcon

Minister of Fire
Dec 25, 2007
1,837
Champlain Valley, Vermont
Buckeye said:
I'm probably not far from where you are so I have had the same conditions. Like others have said, get the wood charred good for about 10-20 minutes and turn the air down about half. Then leave it there for about 15 minutes and close it almost all the way. Leave it open maybe an 1/8" or so. You should see the secondary tubes blowing flames at that point. That will bring the stove temp. up really well. If your wood is seasoned this stove is definately enough to heat a newer 1800 sq ft home. Our first year I probably wasted as much wood as I got heat out of. You think that leaving the air open and seeing all the flames that it has to be hotter than closing the air and not seeing as many, or the ones you see are dancing above the wood. That was the way I was always thinking, bigger flames = more heat. Not True.

Look at my link below. I heat this mass with mostly the heritage. It was built in 1912, no way to insulate the walls, cheap replacement windows that I have to put plastic over and generally not very well sealed up. The past few days my boiler has been running quite a bit, but, when the temp is above 20, it rarely runs. Maybe during the day when we are at work but not when we are home at all.

Here's what I still don't get. If the secondaries are what really gives off the heat and the secondaries are burning gases from the wood, what the heck are they burning from really dry seasoned wood? Wouldn't they blast off more with unseasoned wood?

There's something I'm missing or have gotten wrong here. Can somebody straighten me out? What is dry wood giving off that the secondaries are burning?
 

eernest4

New Member
Oct 22, 2007
603
ct
netzero.com
gyrfalcon said:
Buckeye said:
I'm probably not far from where you are so I have had the same conditions. Like others have said, get the wood charred good for about 10-20 minutes and turn the air down about half. Then leave it there for about 15 minutes and close it almost all the way. Leave it open maybe an 1/8" or so. You should see the secondary tubes blowing flames at that point. That will bring the stove temp. up really well. If your wood is seasoned this stove is definately enough to heat a newer 1800 sq ft home. Our first year I probably wasted as much wood as I got heat out of. You think that leaving the air open and seeing all the flames that it has to be hotter than closing the air and not seeing as many, or the ones you see are dancing above the wood. That was the way I was always thinking, bigger flames = more heat. Not True.

Look at my link below. I heat this mass with mostly the heritage. It was built in 1912, no way to insulate the walls, cheap replacement windows that I have to put plastic over and generally not very well sealed up. The past few days my boiler has been running quite a bit, but, when the temp is above 20, it rarely runs. Maybe during the day when we are at work but not when we are home at all.



*******************************************************************************
Here's what I still don't get. If the secondaries are what really gives off the heat and the secondaries are burning gases from the wood, what the heck are they burning from really dry seasoned wood? Wouldn't they blast off more with unseasoned wood?

There's something I'm missing or have gotten wrong here. Can somebody straighten me out? What is dry wood giving off that the secondaries are burning?
********************************************************************************

Dry wood burns hotter & faster & gives off more heat that the same wieght in wet or unseasoned wood.
Wet or unseasoned or not seasoned long enough wood has a hard time to reach 450 deg and needs to steal heat from the rest of the fire to boil off the moisture.
Wet or high moisture wood steals the heat needed to boil water from the rest of the fire But after(about 45 minutes) the wet wood has dried off in the fire at 450 or 500 deg, it becomes dry wood and starts to burn better. At this time, you will notice less smoke from the chimney and you will need to closed down your primary air so that the fire does not get too hot because you had your primary air opened more that normal tring to get the wet wood to burn. (this takes an abnormal amount of primary air to burn)

after the wet wood dries in the fire, the former high primary air setting (for wet wood) is too much air & the fire gets real hot & burns up your wood load too quick.

Too much primary air just throws your heat up the chimney without doing much to heat your house.

You want 2 get the stove hot ,not get the chimney overhot.
If you don't believe me, try this experiment.
Buy two magnetic stove pipe thermostats (stack thermostats) & place one on the stove pipe 18 inches above the stove and the other one on the stove top.

This allows you to monitor both the stack temp & the stove top temp & know exactly how your stove is burning with different types of wood & different primary & secondary air settings.

These are the gagues that you use to fine tune your stove control settings.

If you have a double walled stainless steel stove pipe, you will need the kind of thermometer that has a long probe & you will have to drill a hole in the stove pipe to accept the probe and maybe a screw in mounting bracket for the thermometer.

Dry wood throws off plenty of HOT GASSES for the secondary air to ignite.

Wet wood throws off plenty of COLD STEAM & MOISTURE VAPOR that cools down the fire as well as the air inside the stove and the last time I looked, hot secondary air can not burn steam or moisture because steam & moisture are both non flamable.

Also, steam & moisture cool down the internal stove temps so that secondary combustion can not
happen or not happen efficiently.

My secondary burn does not work at all with a stove top temp below 500 deg.

I have to exceed 500 deg stove top in order to initiate secondary burn.

You stove may secondary burn at 450 deg or even 400 deg , but the hotter the internal sove temps, the better, more efficient the secondary burn.

I hope this helps.
 

gyrfalcon

Minister of Fire
Dec 25, 2007
1,837
Champlain Valley, Vermont
Thanks. I'm aware of the phenomenon, I'm just not getting my head entirely around the reason for it. I guess the heat suppresssion action of the moisture content is most of what I'm looking for.

I have very dry to pretty dry wood here (moisture meter readings between 20 and 30 inside splits), but don't get as much or as consistent secondaries as I think I probably should from reading here. But the Tribute likes 400-450 a lot and can only occasionally be persuaded to get near 500, and I still haven't been able to figure out the trick to getting it there. With such a tiny firebox, there's not much margin for error, or for experimenting.
 

rwilson

New Member
Sep 18, 2008
59
Northwest Ohio
Thanks for all the suggestions. Looks like I have a lot of things to try! I never thought about smaller splits producing MORE heat, but it makes sense. I'll give all these things a try, and let you know how it works out.

Thanks again.
 

Todd

Minister of Fire
Nov 19, 2005
9,796
NW Wisconsin
CZARCAR said:
if u monitor your chimney for creosote, may i suggest a MAGIC HEAT fluepipe heat exchanger...its a tricky play but can be done.
PM me for further thoughts= i hate to type

Do you own stock in this company? You keep pimping the magic heat creosote factory to just about everyone.
 

rwilson

New Member
Sep 18, 2008
59
Northwest Ohio
I think my problem was the wood I was burning. I invested in a moisture meter (cheap-o from Harbor Freight) and tested the wood I was burning. It was around 27%. Since then I've taken down a dead standing elm and a dead wild-cherry. The cherry tested at 15% and the elm at ~22%. I can now get the fire very hot and the stove up to 450 in 45-60 minutes. I've definitely been burning wood that is wetter then it should be (~ 25%), because the wood I have now is burning much, much better. In fact, I think I had a mini chimney fire that burned up some creosote (https://www.hearth.com/econtent/index.php/forums/viewthread/32957/). I'm still trying to figure out if I had a chimney fire or not and what I need to do to make that determination.

Here is how I know get my stove hot...

1). Load stove full with small-medium splits (using dry wood this time)
2). Keep air-intake wide open for 15-20 minutes until fire is really, really rolling. Stove top temp will be around 350. Double-wall stove pipe and front glass are very hot! (This is where I had the "problem" I mentioned in that other thread above).
3). Take air-intake down to about 50% open for another 15-30 minutes until top temp is around 400 - 425. Flames are still very large at this point and the wood is glowing red.
4). Shut air-intake all the way down. Secondary kicks in for about 45 minutes or so, raising top temp to ~450.
5). Run with intake all the way down. Top temp drops down to 400, but stays there for awhile.
6). When top temp drops back down to 300 (after a few hours), I go back to step 1.


I'm a newbie so feedback on my approach and opinions about possible chimney fire are extremely appreciated! Thanks to all!
 

edthedawg

Minister of Fire
Are you reloading every 3-4 hours like that? If so, I still question the wood. I know my wood is marginal at best and if I try to keep it running hot, I'm doing about the same as you. I usually leave the primary cracked open about 1/4" to 1/2" unless we're asleep or gone to work.

For instance: Loaded last night at 9pm, and it was 450 around 10:30pm when I shut the damper and primary. at 6am, the stove was cooled off but still had buildable coals (raked coals in front of primary outlet, put a big split in back, Eco-Firelog sitting on some kindling and shredded cardboard in front of that, 3 other little splits in front and above the EcoFirelog - closed the side door, and had flames within 10 seconds - fanned w/ the door just cracked open a little for 30 seconds, and then shut the door), and the stovetop was close to 400 by 7am. threw two more big splits in for the day, leaving the flue damper cracked open and the primary open about 1.5", and (in theory) the Woodstove Goddess shut the damper and primary before she left... I expect we'll get home around 4:30/5pm and it will have cooled to 200ish again, and we'll start over... With our wood, we're just not going to keep a 400 degree stovetop on an untended stove for 8 hours.
 
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