Is this "normal"

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I have stated I am very paranoid in my previous posts...... But when my stove is loaded and I get it up to 500* and close everything down (bypass and primary air) it will lower to 400* or so...then take off to 650*+ the above temps are stove top...so i know I have 150* before over temp...but it still scares the begeebees out of me that I cant slow it down! I am also getting the crackle noise in the chimney with what sounds like creosote falling down..... Am I just being too afraid of this thing or what? I know I am making creosote by not opening the thing up for overnight and all day.... but if I give it some air... it wont stay constant... it will build and build and I am not a big fan of that when I am not watching it! Is that your experience as well? I have an epa LOPI ENDEAVOR. I am realy close to pitching tjis thing and going back to coal... But I have 10 acres of hard woods and am trying to learn to like this beast!

THANKS AGAIN

PS like tonight I can keep it below 400 and i can make it behave...once over 400 it has a mind of it's own!
 
Keeping it below 400 is not the best way to run the stove. Running it too cool will increase creosote deposits which can be something to worry about. It sounds like it is behaving normally. What is likely happening when you are running it below 400 is poor or no secondary burn. The secondary burn is where the stove will be burning cleaner and hotter. This is a good thing.

However, you do have control over it. To reduce temp to say 550+ at peak, try less wood or thicker splits.
 
Yes, you are probably too paranoid. It does not sound like over heating to me at all. You might also think about buying another thermometer as those things are not 100% accurate. For example, I have put two side by side on our stove. One says it is 500 degrees while the other says it is 430 degrees. On the low end, one says 250 degrees and the other says 200. Also, have you tried a flue thermometer?

Probably what is happening with yours is the same as what happens with ours. When our cat. is turned on the heat really soars. Same thing happens with secondary burn. Once that starts the heat builds fast and is scary at first but when you understand what is happening you'll probably start enjoying it.

Also, what BeGreen says about running the stove at a lower temperature is very true. The stove is meant to burn at a higher temperature to operate correctly.
 
We just got rid of our Lopi Leyden because the same thing happened to us. We loaded it up and it would not slow down for anything. Air was being pumped into it even though we had the air control lever and the bypass closed. It turned out that the bypass gasket was warped and air was going in. You might want to cool it down, stick your hand in there and feel if air is coming in without the bypass being open. If that's the case, it might be a warped bypass, which is a potentially dangerous situation. You may know from reading the threads that the cast parts were manufactured in China...
 
I thought (from reading the threads) that the casting for that stove was done in Vermont by VC. Not so?

What did you replace the Leyden with?
 
Yes, it sounds like you could be a little paranoid. How long have you had the stove? New stoves take some gettin use to. Steel stove can run pretty hot, over 700. Most steel stove manuals state overfire when they start to glow red usually over 900. Are you saying the stove temps won't fall when you shut the air all the way down? Do you have a tall chimney, you might have a little too much draft? Pipe damper may give you more control.
 
Todd said:
Yes, it sounds like you could be a little paranoid. How long have you had the stove? New stoves take some gettin use to. Steel stove can run pretty hot, over 700. Most steel stove manuals state overfire when they start to glow red usually over 900. Are you saying the stove temps won't fall when you shut the air all the way down? Do you have a tall chimney, you might have a little too much draft? Pipe damper may give you more control.

Sorry for the delay, I missed this post. Mine says 800 for over temp reading above the door. The stove temps may fall back temporarily then climb on there own with it fully shut down. My example is wife got stove to 500 something...it backed down to 400 when she shut it down....then with no adjustments..stove shut down completely, it climbed to over 650..about 675 or so, stayed there for about an hour and slowly backed down... again completely closed. This has happened a couple times. Since then I have sealed some leaks in the pipe, at the collar, and at connections, the run away has gotten better (not completely gone) but now for some reason I am gettingg a lot more creosote, even though I am burning hotter and checking almost every piece of wood with a moisture meeter! Today I took about 3 cups out and that accumulated in a weeks time :ahhh:
 
chrisman34, you are running that stove too cool. The only time it sounds like you ran it correctly is when your wife got it to 650 or 675. That's not overfiring, and that is good temp to get it to, then it'll cool back down to 550 or so and leave it there. 400 is way too cool. 400 is usually when I break up the remaining coals and reload.
 
Make sure your flue is clean, then heat that thing up. As others have said, and I concur - you are probably right to be paranoid, but the main worry should be your cool fire gunking up the flue, then when the stove does get up to normal operating temp, the flue lights off as well.

I was in a hurry to get the house up to temp a couple weeks ago and shoveled in an armload of pallet scraps. They lit off and the stove peaked at about 975F. I know the flue is clean and the stove is solid so I wasn't too worried about it. But one sure way to soot up the flue is burning cool, smoky fires.
 
Chrisman34, why don't you try what I now do all the time........don't load as much wood and do not damper at all unless it gets near 650 ish.

I plan to add to a post I made a few months ago in reference to this type of burning, please read it, it could help.

And I do understand your concern about fire............



Robbie
 
Robbie said:
Chrisman34, why don't you try what I now do all the time........don't load as much wood and do not damper at all unless it gets near 650 ish.

I plan to add to a post I made a few months ago in reference to this type of burning, please read it, it could help.

And I do understand your concern about fire............



Robbie

You have 540+ posts....can you give me a link please!

Thanks TO EVERYBODY for all the posts on both my these subjects the last couple days, I didn't mean to resurrect this one, just noticed a post I didn't reply to.... don't want to be a forum hog! I will be trying higher temps, and maybe different wood that seems to be the 2 conclusions so far..... and since I am pretty sure wood is at least half way decent, I am going to have to run the temp up even more.
 
Part 1

Chrisman34, what most people have a problem with is imagining that "draft" has something to do with the stove, or if they get past that, that "draft" is something constant produced by the flue (chimney).

Unfortunately, life is a bit more complicated than that. A chimney produces draft because warm air inside the flue is less dense than the surrounding air. Thats what you get when you heat air at a constant pressure - the density drops with increasing temperature. So, just like in nature where clouds rise off the sea from the sun heating the surface of the water, warm (or hot) air inside a chimney will rise through cooler more dense air around it. The difference is that by being enclosed in a chimney that is essentially insulated (and which, preferrably does not leak) it is possible to add up the boyancy of all the bundles of air in the flue and generate a much stronger draft than what is possible in free air where the flue gasses would be able to mix with surounding air. By mixing with the surrounding air, the temperature difference quickly vanishes and the bundles of air in the flue gas cannot combine their eforts to produce good strong draft. Case in point, most outdoor water boilers and BBQ's.

So now beyond the basic theory, one has to consider what is actually going on when you light a fire with a cold stove. The wood is cold, the stove is cold, the flue is cold as well as the air in it. If you have an inside chimney, the house itself has a "stack effect" since the air below the ceiling is generally the warmest, it is cooler on the floor and (at this time of year) it is quite a bit cooler yet outside. So if you had no stove, just the class A poking into the room (and an alternative source of heat) there would be a really nice draft rushing up into the class A, created by the difference in temperature between the air at the inlet of the class A and the outside air at the raincap multiplied by the length of the class A from begining to end. This is why, with a decent chimney, if you open the door of a cold stove it should start drawing air from the room into the stove immediately. If not, you have a problem.

So now you build your fire with kindling, small splits and 1 or 2 bigger splits. Light the kindling. Normally the draft is fully open and the door is cracked. The damper in your insert is really just a device to bypass the baffle, in other words, provide a direct path for smoke from the fuel to the chimney without doing 2 90 degree and 1 180 degree bends in the process. The draft at this stage is weak, because everything is cold, but to compensate we provide a lot of area for air to enter the stove to reach the fuel. This has the result that it "seems" like the draft is strong, since the flames flicker really strongly and you can hear the air rushing into the stove. NO, the draft is not strong, we have just deliberately provided it with unempeded flow to the kindling. The kindling in turn is fine, which means that it has a lot of surface area compared to its weight, so its volatility is high (in other words it can burn really fast). In reality, we are providing the fire with far more air than what it can consume. The best thing we can now do is to gradually reduce the airflow to the fire, keeping it just higher than what the fire needs to consume the wood. This will provide the greatest heat output from the fire. Some of this heat goes into heating the wood, some goes into heating the stove and the rest goes into heating the flue gasses.

The hotter the flue gasses, the more boyant, hence the stronger the draft. Over time the flue will heat up. Without having adjusted the primary air (and having earlier closed the door), the draft would become stronger and stronger. Within about 5-20 min (depending on dryness of the wood, size of the stove etc) a point will be reached where the stove will be in danger of overfiring unless we restrict the draft by starting to close the primary air. Initially reducing the primary air may cause the stack temperature to go up, since we reduce the excess air (not needed to burn the wood) thus also reduce the amount of air that must be heated. Further reducing the primary air will result in there being less air than fuel (rich) and the stack temperature will start to drop. If the baffle and the inside of the stove got hot enough (at least 600F), they will heat secondary air hot enough that it will spontaneously ignite any unburnt fuel (smoke) in the flue gas. That is why one sees the secondary flames. But secondaries will not happen if the inside of the stove does not get hot enough. Causes could be wrongly installed firebrick, no insulation blanket or firebrick on top of the baffle (generally has to be fitted during the stove install) or most common - wet wood.

Once the flue temperature is up to the 500 degree range (I'm talking a probe style thermometer, not a surface type) coming down off the back of the initial 700-800 degree burn, the draft should be really strong and you would need the primary air closed waaaaaayyyyyy down to maintain 500. If not, the fire is being cooled internally by steam (wet wood) or your chimney has so many leaks that you are totally diluting the hot flue gas with colder air that is being sucked in.

As the volatiles in the wood burn off, the temperature will drop. There will be little flame or sign of secondary combustion. This is normal. If you need a lot of heat, you can now start opening the primary air again to speed up the combustion of the coals which are almost pure carbon. Eventually, there should just be a fine white ash remaining and you sart back at the beginning.
 
Part 2
The reality is that few people have the time to mend their stoves in such a way. Generally a few minutes is allowed to char the new wood and re-heat the stove and flue after a reload, then the primary air is cut back to a point dictated by experience. With dry wood, the combustion process is quite robust and is tolerant of quite considerable "operator error". If your wood is suspect, your results will vary. I have had a few stubborn pieces that I could have sworn were about as volatile as granite and they seemed to sublimate (become progressively smaller and smaller) without showing any signs of burning.

If you doubt all of this, save yourself some time and cut up a new untreated 2x4 from your local hardware store. Dimensional lumber is kiln dried so it is dry through and through. Because it is succeptible to warpage, most sellers keep it safe and dry before you buy it. If you split 2 stove lengths fine for kindling you should just need 1 piece of newsprint and a single match to start the fire. I suspect that you are presently drying the surface of your splits only. Take one that you did a moisture reading on and split it through again. Now re-measure the freshly split face and compare readings. I suspect much higher than 20% moisture content.
 
I would like to thank keitho for what is, in my opinion, an extremely informative post. A lot of information that any woodburner could use.
 
As for fire safety, get yourself some dry powder used in the extinguishers and fill a few baggies. If you do have a fire call the dept. first, throw a baggy in the stove and use the ladder which you have ready to pop a baggy in the chimney. Or even use a long pole and stay off a slippery roof. Some people also keep a garden sprayer set to a fine mist to create steam. One gallon goes a long way. Course the ff dept. will still check for hot spots with their thermal camera but it's a good feeling to be prepared.
 
Wow, thanks again for the responses.. Tonight I ran stack to 350, about all I could get out of it without door open....and i noticed there was no smoke at the cap but about 5-10 feet away it would burst into white smoke. My guess is it's steam... So I guess i have to give into the bad wood theory... guess i shouldn't second guess those that know best! I've been meaning to split a piece and see inside but haven't gotten around to it, but it sure looks like that is the problem tonight. I do appreciate all the help and advice. I am going to fight my way threw this year, only burning when I can baby sit and keep it real hot... and try for better wood next season. I had my property logged in Dec. and already have about 2 cords cut and stacked. Hopefully i can get it dried by next season. I will also dig out the unused wood and stack in the sun to get it dried out. THANKS A LOT!!! I REALLY DO APPRECIATE ALL THE HELP!

Jerry
 
Chrisman34

In a bad situation, the first thing you can do is re-split all your wood into pieces not bigger than 2" in cross section. It increases the surface area and reduces the weight of the individual pieces substantially. Also, when you load the smaller splits in your stove, there will be more air gaps between then, encouraging combustion. This is pretty much standard practice for any emergency situation, whether it be wilderness survival or you have no seasoned wood and an ice storm knocks the power out for several days. Either situation is an emergency and you do what you need to survive and protect your property.

It should not take much more than 1/2 hours work to re-split enough wood for the day and you will be rewarded with a much more manageable fire. It will still be hard to light but easier to keep burning hot and that is exactly what you need to do to avoid heavy creosote deposits. And get yourself a few 2x4's which you cut down to 12-14" lengths to use as kindling. Its really not very expensive and that stuff burns great. In fact, if you are able to obtain construction offcuts, it would be ideal to mix that in with your wet wood. Best of luck.
 
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