Possible Small Chimney Fire - Need advice

[Poindexter]

@bholler , @begreen , is not 1000 degrees F flue gas temp pushing the upper limit of safety, even with modern pipe?

 

[bholler]

@bholler , @begreen , is not 1000 degrees F flue gas temp pushing the upper limit of safety, even with modern pipe?

Chimneys and liners are rated to 1000 continuous and 2100 intermittent

 

[stoveliker]

I have been fooling with this problem for coming up on seven years now.

https://www.hearth.com/talk/threads/regulated-burners-cold-start-tips.140279/

I have no reason to think my draft is unusually weak or strong. With house guests that needed to remain fully clothed I was able to get a 36 hour burn out of my A30.0 with outdoor ambients in the +20 to +30 dF range. It remains my personal long burn record with an active cat, but the house was not warm enough (given the fully clothed guests staying over) for my wife to be in the wardrobe I desire. At -30dF and colder I can burn down a box full of spruce in 4 hours. Everyone here will have better/ stronger draft at -30 dF than they do at +30dF. I conclude my draft is average/ typical and have intentionally not commented on any of the damper conversations I can recall.

The EPA reg requiring regulated burners to get from cold iron to clean plume in 20 minutes should not be on the books because it is not safely attainable by average burners using average fuel in average installs. I don't know any above average burners with above average fuel that can do it, not one. Period. See you in court.

Please keep in mind, first lit kindling to engaged combustor is not the same interval as first visible plume of smoke at opacity of 50% to clean plume. There have been several folks in the last few years mucking about with engaging their combustors early. The general idea is "I know my stove, I know my probe runs about ten minutes behind reality, I know my fuel, therefore I have been engaging my combustor 10 minutes before it would get to the active zone and I haven't broken anything yet." But none of them, zero people, have been able to photographically document that process got them to clean plume any faster.

I will quietly admit I have fooled around with engaging my combustor early back in Feb 2015 and I found no consistent measurable improvement in total time to clean plume.

If you can think of something I haven't tried I am all ears, but I would very much prefer to get the bad rule off the books or ammended.

You are understandably focused on the plume. The statement was "light off the cat". The latter is what I commented on. Of course these two things are related, but the former is not instantaneously following the latter. Light off is just that. Plume good is optimal running of the cat.

I agree the rule better be changed as not all are as conscientious as folks here.

 

[BKVP]

You saw "white smoke"?

 

[BKVP]

I don't think it can be done safely with a typical average install. One thing to keep in mind is registered users here are among the most conscientious burners in North America. BKVP says so several times annually and mentioned "us" as a group in particularly glowing terms just in the last week or two.

From previous F2F conversations with Chris over the years, the typical burner, who isn't registered here, is running fuel at 20-22% MC, and all the stoves from all the manufacturers are designed around that finding. When we start loading fuel at 18-16-14 % we are pushing the design envelope already.

So let us just ask Chris and get it over with. @BKVP, loading fuel at 15-20% MC on a typical/ average chimney how fast can we reasonably expect to consistently get to active combustor without overheating our chimney pipes?

Depends upon the substrate. Ceramic combustors, from a cold start with #5lbs of kindling, about 20-25 minutes. With the metal monolith combustors, same conditions, about 15 minutes.

 

[elmo_4_vt]

OP here:
Just to close the loop on this thread in case someone in the future is reading, I had the Sweep out today. No evidence of any kind of a fire and very little soot or build up. The only places that really produced anything inside the pipe was at the very top. He did everything from inside going up through the bypass (which surprised me). He also pulled out the combustor and verified it looked good.

So at this point, I guess I just got the pipe a little too hot, and no actual fire occurred, which is comforting. I really appreciate the help and guidance from the group.

He was a little surprised at the build-up inside the stove and on the glass, but he attributed that to either burning the loads at a lower temperature (slow burn because it hasn't been very cold) or my wood not being dry enough. I still haven't gotten the moisture meter back out to verify more pieces in the IBC tote I'm using, or the ones next on deck, but will get that done this weekend. In the end, it's the driest I have, so it will have to do until next year, now that I know it's not effecting the pipe much either way. Selling our old house (and most of the fire wood that was stored there) has really put me behind on storage and drying. I have a couple cords waiting to be split, but most of that is white/red oak and some locust, so it may not be ready for next year at this rate. I may have to break down and purchase some for next year or do a trade with a friend who is stocked a couple years out.

I've been happier slowly turning down the stove as it heats up and chars/burns the wood, and once I get the thermometer for the pipe installed this weekend, I'll use that as the baseline for setting the start-up times and thermostat set-points.

The only down side is that the sealing material around the combustor fell apart when it was pulled out today, so I need to call the stove shop and get that ordered tomorrow.

Don

-

 

[stoveliker]

Yes, have gasket available before you pull out the cat. It will always fall apart.

 

[Poindexter]

So at this point, I guess I just got the pipe a little too hot, and no actual fire occurred, which is comforting. I really appreciate the help and guidance from the group.

You're welcome.

 

[Poindexter]

Depends upon the substrate. Ceramic combustors, from a cold start with #5lbs of kindling, about 20-25 minutes. With the metal monolith combustors, same conditions, about 15 minutes.

Thank you sir. I will make a point, before 02-28-22, to find out how big a pile I need to equal 5 pounds of kindling, and I will set it on fire. I will also weigh my typical kindling load for a cold start, I suspect the latter will be at or under 4 ounces.

FWIW it is not explicit in either of the Tacoma or Fairbanks regs if I could do a cold start with 5# (zounds!) of kindling and a hot reload both in the same hour of operation related to plume opacity.

If you know of anyone who ever gets ticketed for this BS infraction please let me know so I can cash in some of my plentiful airline miles and plentiful PTO so I can show up with my tattered notebook, in starched whites, with bells on, to explain to his honor using words of one syllable or less why the simulacrum from the EPA should be tarred and feathered post haste with great vigor by the body politic.

Again, my thanks. The "tail" (barring EPA interference) on my stove's burn extends from September into April, and my tolerance for impertinent whippersnappers can be measured most accurately in Angstroms. At a bare minimum that reg for typical users of catalytic stoves with legal fuel at 20%MC should allow 35 minutes of plume opacity at 50%. I don't know how fast modern EPA non cat stoves can get there, but it should be faster than catalytic stoves can do it; desirable for men who cannot ply their troth in a biblical manner, but ultimately useless for the environment.

Peace out.

 

[jetsam]

Here's my blanket statement: If you think something's not right in your flue, you should look.

Takes 5 minutes, and a wifi endoscope long enough to scope out the whole run costs $30 on amazon.

If you have to call The Guy to come do it for you, that's a substantial barrier to you actually getting it done, and an even higher barrier to you getting it done frequently. (And yes, you should be looking frequently as you get to know a new stove.)

 

[Poindexter]

Yes, have gasket available before you pull out the cat. It will always fall apart.

This exactly. On BKs at least, anytime the combustor is pulled a new gasket is required.

 

[jetsam]

This exactly. On BKs at least, anytime the combustor is pulled a new gasket is required.

Unless you make stainless steel shims to go around the perimeter of the cat.

Frequent cleaning has been awesome for my elderly cat.

 

[Poindexter]

You are understandably focused on the plume.

There are a number of folks, even here among the consciegenti, who equate engaged combustor with clean plume. It simply isn't so.

If engaging the combustor results in a clean plume instantly, there are four possible explanations.
1. The plume was already clean before the combustor was engaged
2. The plume is now, after engagement, moving out at greater than the speed of light rendering the plume invisible
3. The outside observer cannot accurately distinguish smoke from steam
4. Squirrel!

Take your pick. I find one to six minutes after combustor engagement results in clean plume, with a strong correlation [qv] to the 'hash' mark on my combustor probe.

 

[Poindexter]

Here's my blanket statement: If you think something's not right in your flue, you should look.

Takes 5 minutes, and a wifi endoscope long enough to scope out the whole run costs $30 on amazon.

If you have to call The Guy to come do it for you, that's a substantial barrier to you actually getting it done, and an even higher barrier to you getting it done frequently. (And yes, you should be looking frequently as you get to know a new stove.)

I don't know for sure where the cutoff is, but I do agree with jetsam. At eight cords per year local my chimney is my problem. If I move somewhere moderate and only burn four cords annually, my chimney will remain my problem until I relax from looking at it lots.

 

[Poindexter]

Unless you make stainless steel shims to go around the perimeter of the cat.

Frequent cleaning has been awesome for my elderly cat.

I got nothing man. Up here at 64 degrees north latitude a weak cat is a replaced cat. If this works for you down south, carry on. I will check the green room tomorrow to see if you want to talk about snow tires. I am not here to tell folks what they should do. I am here to explain what works for me up here.

Ultimately it comes down to money and need. My favorite tires up here are $$$ down there, and $$$$ up here, but they are awesome tires. If you don' t need Hakkapeliittas you shouldn't spend the $ on them.

I personally replace my cat every 10-20 cords. I save money doing that. Doesn't mean everyone else should do the same. It depends on how much you spend on propane or electric, how many BTUs you suck down every year, and how expensive wood is for you.

 

[elmo_4_vt]

Here's my blanket statement: If you think something's not right in your flue, you should look.

Takes 5 minutes, and a wifi endoscope long enough to scope out the whole run costs $30 on amazon.

If you have to call The Guy to come do it for you, that's a substantial barrier to you actually getting it done, and an even higher barrier to you getting it done frequently. (And yes, you should be looking frequently as you get to know a new stove.)

Got a link? I'm game, but don't see anything that would make sense at that price point. Go in from the bottom or the top? Care to share some examples or point to a good thread?

With me being new to stand alone stoves in general, it was worth it to me to pay someone for the second opinion and confidence that brings. In the future, seeing that he went in from the bottom for the cleaning (that wasn't possible on my last insert), it means that I can do a lot of the maintenance and inspection myself, and be confident about it.

For what it's worth, with the Condar temp probe in, it seems pretty easy with my setup to get things above 1,000* if left wide open for 20+ minutes. Most times on a hot reload, I'm starting to turn it down by 12-15 minutes to keep it around 800-900 reading, taking into account the delay on the probe. I may have to purchase a thermocouple for my fluke to do some more testing and get quicker results.

Don

-

 

[jetsam]

There are a number of folks, even here among the consciegenti, who equate engaged combustor with clean plume. It simply isn't so.

If engaging the combustor results in a clean plume instantly, there are four possible explanations.
4. Squirrel!

Do squirrels really burn that clean?

Maybe we've been going about it wrong burning wood all these years...

 

[jetsam]

Got a link? I'm game, but don't see anything that would make sense at that price point. Go in from the bottom or the top? Care to share some examples or point to a good thread?

With me being new to stand alone stoves in general, it was worth it to me to pay someone for the second opinion and confidence that brings. In the future, seeing that he went in from the bottom for the cleaning (that wasn't possible on my last insert), it means that I can do a lot of the maintenance and inspection myself, and be confident about it.

For what it's worth, with the Condar temp probe in, it seems pretty easy with my setup to get things above 1,000* if left wide open for 20+ minutes. Most times on a hot reload, I'm starting to turn it down by 12-15 minutes to keep it around 800-900 reading, taking into account the delay on the probe. I may have to purchase a thermocouple for my fluke to do some more testing and get quicker results.

Don

-

I don't want to endorse a particular product, but you can search for either "boroscope" or "endoscope" on Amazon and get some lot of choices. Pick one that is longer than your flue and has a light source on it (I think most of em do).

I have a cheap Depstech screenless one (you connect via wifi and see the video on your smartphone). It works fine for what I need it to do.

If you don't have that but do have a ladder and a flashlight, the condition of the very top of the flue is a good indicator of how your burning habits are working out. It's the coolest part of the system, so if you're going to have creosote, you should see it there first.

 

[bigealta]

Good lighting is Key to the boriscopes, I used a cheap ebay one ($15-20), with usb port into computer, to scope some 4" drain lines. The light was just barely bright enough to see in those dark pipes.

 

[stoveliker]

Do squirrels really burn that clean?

Roast, not burn!

 

[BKVP]

Do squirrels really burn that clean?

Maybe we've been going about it wrong burning wood all these years...

Squirrels are everywhere! I can be in the middle of a conversation and they just walk past my door at home, office window, powerlines while driving....