Had Chimney Fire.............now what?

[longboarder2]

right now, i have access to beech, maple, locust, and oak. some of the oak was a standing dead tree. i get my wood from a local tree service, so when he calls me to pick it up, i can pick and choose what i want. i put a concrete paver follor in the car port and the sides are fully open, just covered on the top. i used to split my wood quite small, but this past year, used larger pieces---i will be going back to much smaller splits in the future!

the carport is on the south-facing side of my larger garage---full sun all day and when there is a breeze, it gets back there.

 

[BoilerBob]

When I read this post, it brought back memories of what I used to do when I started to burn wood in my boiler. I thought the water temp had to stay at 180, so I kept loading boiler, hauling out ashes (unburnt charcoal), load boiler again, haul out ashes, load again etc... I was burning way too much wood, idling most of the time, making creosote, cleaning chimmney and boiler constantly.
I used to burn 8 cord per season, now I burn 5 cord per season. Just by loading the boiler differently and burning dryer wood, no more creosote, I now clean chimmney once per season and I get 2 cups of gray dust. I now space out my reloads, I wait till water temps drop to 120 - 135 so I can burn hot fires, and reload amount according to outside temps, it doesn't take long to get used to this.
I don't set back thermostat at night, the boiler water cools off before morning so when I get up the temp in the house is cooler, which is OK for sleeping and ready for me to rake coals and reload, usually full load to warm up the house for the girls when they get up. It might idle a bit at the end of the burn, but the wood is now charcoal and dry so no creosote.
I am not saying you have to do it this way, just experiment with what will work for you.

PC

 

[91LMS]

nova do you run a gasser or conventional indoor boiler?

 

[BoilerBob]

91LMS - 36 year old HS Hedler - Tarm conventional non efficient indoor boiler

 

[ChiefChicken]

Mike,

I may have missed it in all the text, but I have to ask anyway. Was your chimney fire an actual "chimney" fire where it started with creosote burning inside your chimney? Could it possibly have been a bad joint in the pipe that let embers out into the wood framing? Was there evidence of burning creosote? The crackling sound you described sounds like just the wood framing burning. A full fledged chimney creosote fire makes more of a roaring sound.

This is just something I was wondering about, not trying to start any trouble!

Eric

 

[91LMS]

thanks nova, in the process of installing my non gasser (should be ready for the 4th of july at this rate, lol) but learning about operation with no storage via this thead and others will hopefully keep my creosote build-up down.

 

[JrCRXHF]

I have a SF-260 with 3800sqft what i do is turn off or down the heat during the day then burn hard when i get home to pull the heat up on the house. The other thing i do is i have 2 different systems gas and wood. I preheat the water for my gas boiler so my wood boiler runs its own loop. I have been burning ash that sits around 15-18% and a little 20% maple when i have a really good coal bed. I have cleaned out my boiler 2 times this winter and i have 1/8 or less build up on in the exit of the boiler. The other thing i do is run a stainless 6" liner in with pour in insulation down the chimney and then 1.5" blanket on the exhaust pipe going all the way to the wall to keep the EGT as high as i can. Most of the time i don't have any to very little smoke coming out of the chimney besides for a short time when i am loading.

I agree storage is the best if you have room i also run the creosote converter once a week with a hot burn.

 

[longboarder2]

eric,

it's hard to say what came first the chicken or the egg----i heard the crackling in the wall, but the wall was not hot and there was no odor. i went outside to see the top 12" of the chimney tower on fire which was about 12 feet above the roof so, my original thought was that the creosote builup on the flue topper caught fire and because of the low clearance to the top of the chimney tower, it just migrated south and the burning in my attic and walls were a result of falling embers from the "above roof" tower burning and falling down. i figured the crackling was the tower fire echoing through the hollow chase.

after looking in the flue pipes that had been removed, they were generally open, but had some scale in them, one had a tar-like black residue in it, and there was some charred buildup at the joint of two flue sections. the removed segments were badly burnt from the tower fire, it's hard to say where it started. i looked at the sections still in the framed chase and they are discolored like they got hot, but they were also sprayed down w/ water by the fire company. there are no gaps in the sections though where an ember may have escaped. when i saw the discoloring of those, that's what made me think the fire started lower in the flue, rather than at the topper. no jet engine noise to speak of though.

 

[ChiefChicken]

Thanks for the reply Mike. The important thing is that you and your family are safe. Everything else can be fixed.

 

[longboarder2]

nova,

thanks for the tips---i was suffering the same misconception---boiler at 180 all the time. at night i was filling the box with wood, turning down thermostats, stuffing it again in the morning to mee the wake time demands---apparently doing it all wrong.

wood is no object, so i'll definitely be burning more, smaller, hotter fires and making sure it's not idling through the night. during the day when the outside temps are over 30, i plan to run the dump zone more and allow the fire to burn out, rather than smoler---looks like it's better to have to re-light in the evening than to have the unit idilng.

eric, thanks for the sentiments.

 

[longboarder2]

Here's the update on my orig. post:

it has been two weeks since our fire and things are moving along nicely. sucks to burning oil again, but what can ya' do. we have begun framing repairs in the attic and second floor and the chimney crew is showing up monday to begin work. wanted to see what some of you thought of the upgrades and equipment and see if there was any more advice based on the reconstruction changes.

the wood boiler will now be exhausting through a 7-inch triple-wall flue pipe. they are using Selkirk materials. the chimney tower will still be wood framed, but will have a stone veneer exterior. the flue topper is going to be taller than the last and will be a more open metal mesh design. the topper is going to sit about 18" above the top of the chimney tower. the selkirk flue pipes will be insulated with a fire-retardant insulation and there will be metal panning for fire stopping @ each floor and the roof. the chimney tower is going to have a stainless top with metal rain collars and weatherproofing----NOT flat, galvanized, with roof cement sealer.

i have purchased some wood that was split last summer---that will be stacked in the carport this week with the remaining cord from this year. it's mixed hardwoods and we plan to burn it next winter---should be about 16 months old by then. i have begun splitting wood for the following season---oak, locust, beech, some maple. 75% is locust. all of the splits are between 3 and five inches thick---as a general rule, if i can't grab it by the end with one hand comfortably--it's too big and gets split again. space in the carport is limited, so the wood we are currently splitting will be covered on top w/ a tarp.

what do you guys think of the selkirk flue equipment? any installation tips? the insulation a good idea?
when i put my moisture meter in the wood next november, what are good content readings? after that, the calendar is the moisture meter.

we plan to treat the boiler more like a woodstove---get it going hot and only add wood when the load has burned down to a nice bed of orange coals. add only one or two splits at a time. build up the heat in the house and basement in the evening and keep the air door open and allow the fire to burn out @ sleep time instead of idling. re-light in the morning. we also plan to not even run the wood boiler if the outside temps are over 38 degrees.

sound like we're heading in the right direction?

 

[willworkforwood]

.... i have purchased some wood that was split last summer---that will be stacked in the carport this week with the remaining cord from this year. it's mixed hardwoods and we plan to burn it next winter---should be about 16 months old by then. i have begun splitting wood for the following season---oak, locust, beech, some maple. 75% is locust. all of the splits are between 3 and five inches thick---as a general rule, if i can't grab it by the end with one hand comfortably--it's too big and gets split again. space in the carport is limited, so the wood we are currently splitting will be covered on top w/ a tarp.
..... when i put my moisture meter in the wood next november, what are good content readings? after that, the calendar is the moisture meter.
we plan to treat the boiler more like a woodstove---get it going hot and only add wood when the load has burned down to a nice bed of orange coals. add only one or two splits at a time. build up the heat in the house and basement in the evening and keep the air door open and allow the fire to burn out @ sleep time instead of idling. re-light in the morning. we also plan to not even run the wood boiler if the outside temps are over 38 degrees.
sound like we're heading in the right direction?

Wow, it sounds like you are going from always fully packing the boiler, to shutting down at night and using oil until the morning re-light? That would be ok, if you don't have a problem using some oil, but there's probably a middle ground where you can partially load the boiler on colder nights. Once you get to the point of having all fully seasoned wood (20% or less), you may be able to be ok with some idling at night. I think in your case the big creosote build-up came as a result of; poorly seasoned wood + far too much idling from always fully loading + highly unusual warm weather. If you improve the wood MC significantly, and also get normal cold temps you're already way ahead in the right direction, and some idling at night is unlikely to cause anything like this years chimney fire. Burning just a few splits whenever possible is always better than idling, and it's definitely a good idea on your part to proceed with caution. But in time you may find that with completely dry wood, you can get back to running the boiler through every cold night.
If you want the oak seasoned by next fall, it needs to be split 3" or less (often referred to on Hearth as toothpicks). I don't burn locust - others can chime in on split size for that species. The maple should be fine. The general consensus is to leave firewood uncovered until sometime in late Fall. You are definitely heading down the right road now - cut as much wood as fast as you can (think 2015). Good luck with it!

 

[longboarder2]

thanks for the reply.

for the most part, our thermostats go down four to five degrees at night, usually starting around 12am, then come back up between 530 and 7am, with each one coming to wake temperature about 15 to 20 min apart, so we shouldn't burn much oil @ night.

i stagger them so i don't have five zones of heat calling the boiler for water all at the same time.

the house is only 4 years old and well-insulated, so during the night, we only lose about a few degrees across six or eight hours. unless it's in the 20's or we actually get winter conditions like wind and snow---this year has been like winter in the tropics here.