VC Vigilannt Got away from me tonight

[Kenster]

I had a slow starting fire tonight. Went for sometime barely burning. I added a few pencil sized cedar sticks. Left it in vertical mode with the door cracked just a wee bit. After a while it was going pretty good so I top loaded a couple of good sized splits, closed all the doors and left it. About twenty minutes later I could smell a real acrid odor. There was a loud crinkling sound coming from the flue, which is straight up about twenty feet and through the roof. The surface temp of the fire box was only about 600 so I don't think it was overfiring. I went out to look at the top of the chimney and there was very little smoke and no sparks or flames. I shut the stove down to horizontal immediately and closed the thermostat vent and the secondary intake. After a while it cooled down to about 450. Still smells in there.
I'm wondering if I had a fire in the flue.

Which brings up the question: Is a chimney fire inside an all metal flue/chimney all that serious? Especially if you catch it right away?

 

['bert]

One of the most dangerous things from a chimney fire is the hot embers that land on your roof. Therefore all chimney fires have equal opportunity to start your home on fire. Unless your roof is covered with 2' of snow like mine right now. :-S

 

[Kenster]

We have an all metal roof.

 

[Battenkiller]

I could smell a real acrid odor. There was a loud crinkling sound coming from the flue, which is straight up about twenty feet and through the roof. The surface temp of the fire box was only about 600 so I don't think it was overfiring. I went out to look at the top of the chimney and there was very little smoke and no sparks or flames. I shut the stove down to horizontal immediately and closed the thermostat vent and the secondary intake. After a while it cooled down to about 450. Still smells in there. I'm wondering if I had a fire in the flue.

You should put that thermometer on the flue pipe instead of the stove top, or get an extra one and use two. If I'm not careful, it's real easy to pin the flue pipe thermometer (900ºF) on my Vigilant once it gets going good in the updraft position. I'll bet you were smelling the pipe getting up higher than you've gotten it yet. You really shouldn't be able to smell anything coming from the inside of the pipe as long as your draft is pulling hard. Those sounds could be from rapid expansion of the pipe joints, or they could have been from burning off creosote in the lower part of the flue. That usually makes a sound almost exactly like dropping change down a pipe when you shut the bypass damper.

600ºF is nothing for the top of my Vigilant. It easily climbs to 750º in updraft position with a half-full box and the inlet air halfway open. If a 600º stove top temp is unusual, you are not running that stove hot enough IMO. Flue temps should be at least 350º during all but the tail end of the burn. If not, then you were surely burning off accumulated creosote inside your pipe. Is that a chimney fire? Some say yes. I feel that if you shut the bypass and the inlet air and the stove quieted right down, no harm was done. If it continued to burn vigorously in spite of all your efforts, then you definitely torched the entire flue and you probably would have seen that from the outside.

 

[BrowningBAR]

I had a slow starting fire tonight. Went for sometime barely burning. I added a few pencil sized cedar sticks. Left it in vertical mode with the door cracked just a wee bit. After a while it was going pretty good so I top loaded a couple of good sized splits, closed all the doors and left it. About twenty minutes later I could smell a real acrid odor. There was a loud crinkling sound coming from the flue, which is straight up about twenty feet and through the roof. The surface temp of the fire box was only about 600 so I don't think it was overfiring. I went out to look at the top of the chimney and there was very little smoke and no sparks or flames. I shut the stove down to horizontal immediately and closed the thermostat vent and the secondary intake. After a while it cooled down to about 450. Still smells in there.
I'm wondering if I had a fire in the flue.

Which brings up the question: Is a chimney fire inside an all metal flue/chimney all that serious? Especially if you catch it right away?

Absolutely nothing to worry about.

"There was a loud crinkling sound coming from the flue"
It happens often when the fire is roaring and you have a good, strong draft. The main negative in this is that you are losing a lot of heat up the chimney. No damage will occur (unless you let the stove temps to continue to climb, but that is unrelated to the 'crinkling' noise). Switching to horizontal mode or putting in a pipe damper, or closing the air controls calms things down.

It definitely was not a chimney fire based on your description. But you probably did have flames getting sucked up the pipe from the strong draft.

Again, nothing to really worry about.

 

[Kenster]

I realized that a 600 degree surface temp was no big deal and I knew I wasn't about to overfire the stove. I didn't really think I had a chimney fire but I think it was definitely torching some creosote in the bottom of the flue, hence the smell. Today, when I was cleaning out the ashes to prep for tonight's fire I noticed a very large pile of creosote flakes at the bottom of the flue behind the baffle. I'm guessing as the flames from a high fire in vertical mode were burning these creosote flakes.
Anyway, no harm done other than stinking up the house, requiring me to open some windows with 34 degree temps outside. And I know I need to monitor the stove more often and switch to horizontal burn quicker so as not to lose so much heat.

 

[nojo]

Also not seeing any smoke comeing out of your chimney is a good thing and is how your stove should run. Do you normally see smoke?

 

[Kenster]

Also not seeing any smoke comeing out of your chimney is a good thing and is how your stove should run. Do you normally see smoke?

Sometimes I have a little bit of smoke. I haven't been doing this long enough to get two or three years ahead on seasoned wood. Most of what I've been burning lately is recently split wood that has been dead and down for at least a year if not more. I'm going to have to live with that through the rest of this season, which should not be much longer down her in east central Texas.