Over Firing an Insert

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jadm

New Member
Hearth Supporter
Dec 31, 2007
918
colorado
I have read many threads about over firing a free standing stove. One minute stove is fine, next temps. are climbing uncontrollably.

I am breaking myself in with a new insert. It is larger than my old unit and therefore can hold more wood.

At this point all I feel like I have achieved has been burning more wood to get the same results I got with my smaller unit.

I have gotten it up to 450*-500* with maybe 3 or 4 splits and then shut down the air so that it will burn awhile.

Doesn't seem like it is burning any longer than my smaller unit. I just have to keep feeding it.

From what I have read I think I should be putting more wood (3/4ths full) in it to prolong the burn.

Herein lies my problem. I am afraid that if I put more wood in it will exceed the 500* I am already getting and I will end up with too hot of a fire.

I know many of you don't bat an eye at high temps. but they scare me to death at this point. Maybe when I know more about this unit I will be braver. At this point I am overly cautious.

My husband is already scratching his head and wondering why I got a bigger unit (He isn't a wood fanatic.) when all he sees that it does at this point is eat more wood. ( He does like how this one looks. :) )

I read somewhere that inserts are less likely to over fire because of the blowers that surround the fire box with cooler air. Is this true?

Any insert burners out there with experience in this department?
 
You have a Jotul. Dont' worry about stove top temps until you are above 700 (and that is being conservative) I don't close down on the air until the stovetop is 550-600 degrees.
 
Agreed, and to repeat, you are not near overfiring the stove. Overfiring temp is closer to 900 degrees. The stove will not use less wood than the Napoleon 1101. In the shoulder seasons the C550 might actually use a bit more. There is more mass to heat up with small fires. Yes, running normally, a bigger stove will consume more wood, potentially a lot more. And as a result, it will put out more heat, potentially a lot more heat. That is why you selected the C550 instead of the C450, right? To expect the insert to have the same burning consumption as the Napoleon, with about half the capacity, is not realistic.

For longer burns, get a good fire established and let it burn down to coals. On refill, uses a mix of medium and larger splits and fill it at least 3/4s full. Let the wood catch fire, start to char and then reduce air down to about 1/2 to where a good secondary burn is established. Expect the stove to hit about 650 degrees. It might even peak at about 700 for 15-20 minutes.

Sooner or later, you will have to find out the capabilities of the stove, but if you wait too long, it's going to be awfully hot in the house. Especially if it's 50 outside.
 
BeGreen said:
. Yes, running normally, a bigger stove will consume more wood, potentially a lot more. And as a result, it will put out more heat, potentially a lot more heat. That is why you selected the C550 instead of the C450, right? To expect the insert to have the same burning consumption as the Napoleon, with about half the capacity, is not realistic.

Trying this quote thing to respond to both of these comments. Please bear with me.... YES, I did get the 550 because of the size of the fire box and it's potential for more heat. The insert is fine. It is my impatience that I am struggling with and my fear of taking it up to the higher temps. after reading threads where stoves were behaving 'normally' when suddenly they began to climb uncontrollably to way higher temps.



[quote author=''BeGreen" date="1204411443"].For longer burns, get a good fire established and let it burn down to coals. On refill, uses a mix of medium and larger splits and fill it at least 3/4s full. Let the wood catch fire, start to char and then reduce air down to about 1/2 to where a good secondary burn is established. Expect the stove to hit about 650 degrees. It might even peak at about 700 for 15-20 minutes.

Sooner or later, you will have to find out the capabilities of the stove, but if you wait too long, it's going to be awfully hot in the house. Especially if it's 50 outside.[/quote]

I am afraid of loading it up as you, and others, have suggested and having it climb out of control. I have been adding less wood than I should to see what happens to the temps. It has been warm here so I haven't had a day yet where I have kept a fire going all day. When cold weather comes back I'll get more of a feel for this.

Back to my original question: Are inserts less apt to over fire because of the layer of air around the box that is fed by the blowers?

I know that I can't shut the primary air all the way down with an insert like you can with a free standing stove. And I know I have no control what so ever with the secondary air flow.

In other words - in the event of temps. climbing out of control I have less control than someone with a free standing stove.

Before loading this unit up I want to be prepared.I don't feel prepared with this unit at all yet because I don't have enough experience with it to know what to do in the event it begins to run away on me. I felt comfortable with the Napoleon because of my experience with it. I get scared with this one because it holds so much more wood and can get so much hotter...
 
The first thing is to understand what is really overfiring. Until that is clear, you are living in fear. How many times did the Napoleon overfire? We've had reports here that Napoleons like to burn hot it's possible that if you had the IR thermometer at the time of burning in it you would have seen some pretty high temps. (>800 deg).

The second thing is to know that even if the C550 does get a high spike in temperature, it isn't going to stay there. Burning for 20 minutes at 800 may be exciting, but it is not overfiring, just burning robustly. There is a difference. What is the worst thing you anticipate happening? I can assure you that the stove will not melt; the glass will not break. As long as the flue liner is proper the greatest drama is likely to be an impressive amount of heat. You might melt a few candles, but I think the stove can take it. The question is, can you? Whatever you try,,, Don't Panic! ;-)

I'm poking a little fun, but really, this is mostly psychological. Take small steps if that is what you need. Each one will increase confidence and knowledge. Enjoy the stove and relax a little. You will be fine. FWIW, to my knowledge, an insert has no more protection against overfiring than a regular stove except that running the fan on high will cool down the firebox a bit more quickly. I think with a full load of wood you will find the stove spiking up around 650-700 degrees, then settling down to a steady 550-600 as long as the air control is dampered down. Once you've done this a few times and it's keeping you toasty while it's zero outside, it will become routine.

PS: looks like you have the quotes down pat.
 
BeGreen said:
The first thing is to understand what is really overfiring. Until that is clear, you are living in fear.

I'm worried about a chimney fire due to high temps. I guess I was confusing the two things.

BeGreen"date="1204428584 said:
PS: looks like you have the quotes down pat.

Thanks for noticing. :P but I'd be lying if I pretended that I really knew what I was doing. :roll: I considered it a lucky try and will now see if what I did will work again. If it does then you can congratulate me. :cheese:

What I am really proud of is the bold type. I have that command down cold.

Gives me hope that I can learn new things. :lol:
 
That's right, a chimney fire is not the same thing as overfiring. Ironically, one is at greater risk of a chimney fire by burning consistently at low temps than burning at high temps, especially with an exterior chimney. A chimney fire needs a substantial accumulation of creosote in the flue for fuel. If the liner was cleaned when the new stove was put in, you need not worry. Your wood is good and the previous stove was also a clean burner, so the risk is very low, especially with a liner.
 
BeGreen said:
That's right, a chimney fire is not the same thing as overfiring.

Audible sigh of relief.

All this time and I thought they were synonymous.

Tomorrow, weather permitting, I am heading for the higher temps. :coolsmile:

P.S. Looks like I finally got the quote thing down too. Small miracles. :)
 
Another term I noticed that may be confusing is "runaway fire". That also is not synonymous. A runaway fire is not a technical term, but a general condition where the operator can not control the fire and it keeps accelerating hotter. But this could have nothing to do with a chimney fire and overfiring the stove. True, they could be related, but not necessarily.

Overfiring: Stove burning too hot, well above design temperatures
Chimney fire: spontaneous ignition of creosote deposits in the flue
Runaway fire: A fire which does not respond to operator control
 
BeGreen said:
Runaway fire: A fire which does not respond to operator control

Can't help adding another one to the list:

Runaway brain: A brain which does not respond to operator control. :gulp:

I have had a lot of experience with that one lately. :exclaim:

Thank-you so much for all of your help.
 
Good one. That is usually what happens when the stove temps "appear" to runaway, the operator "thinks" the stove temps will climb to the stratosphere and overfire the stove, thus igniting a chimney fire. Your avatar is the right approach, don't panic. Stay calm.

I've occasionally had stoves hit over 900 degrees, usually due to operator error*. Other than being a bit exciting, giving off the unique aroma of fried dust and putting out a prodigious amount of heat, all was fine once the stove cooled down. But a castiron or steel stove going up to 750 with a full load of dry wood in a hot stove is not unusual nor reason to panic. I think many folks burning when there are sub-zero temps outside would consider it a desirable feature.

*Operator error =
1) not checking that the ashpan door was tightly closed
2) putting a large load of very dry wood on an already very hot bed of wood that was still outgassing
3) getting distracted and leaving the air control wide open
4) putting too many Prest-Logs on a fire
 
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