I've completed a thorough inspection for cracks and can't find any where they could mix with the flue gases. Only the 2 small ones on the front inside the seal area.
Worst Creosote I've Ever Seen
- Thread starter wkpoor
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wkpoor said:
I think you are right, the shiny stuff is worst and the powdery stuff the most harmless. But at 3/4" thick, I'd figure you have what I call the "crunchy" stuff, somewhere in between. Not as hazardous, but maybe not totally harmless, either?
Anyway, maybe what I should have said was: trade the lumber to someone who can burn it more efficiently. Meaning I think the stove would overfire on that stuff if you let it burn hot enough to keep flue temps higher. To keep the stove around 500F, how are you setting the air supply? Are you shutting it right down early in the burn?
With various stoves over the past few decades, I've found it beneficial to look to the chimney discharge for feedback on what was going in in the stove, like with different wood, placement, draft settings, etc. ("Touchstone": any visible smoke is bad.)
Simple experiments to find out the parameters of the stove & installation. Then, I'd try to stay within the stove's happy operating envelope. And watch for any significant changes to that.
I'd suggest that what you're burning and how you're burning it results in unburnt volatiles, and your flue conditions cause that to condense there. TWO problems.
Simple experiments to find out the parameters of the stove & installation. Then, I'd try to stay within the stove's happy operating envelope. And watch for any significant changes to that.
I'd suggest that what you're burning and how you're burning it results in unburnt volatiles, and your flue conditions cause that to condense there. TWO problems.
Pretty typical install so I doubt it. Also buildup was equal in stove pipe and chimney. I'm really wondering if the reducer is acting like a damper.branchburner said:
soupy1957
Minister of Fire
BrotherBart said:
Interesting point............How would I know if I "popped a weld?" Does a popped weld actually affect the way a fire burns? How? Lets in too much air and forces a hotter burn than normal? What are the safety concerns with a popped weld?
-Soupy1957
wkpoor said:
I would think so, to some degree. If the stove is designed for an 8" flue and you run it at capacity, there must be at least some slowdown of the release of smoke and heat. Along with that, here are the variables I would examine:
- do you have an inline key damper, and how is it set?
- how close to capacity are your loads of wood?
- what is the size/dryness of the wood?
- how far closed are you setting the air intake?
It sound like a situation similar to what we had with our old airtight Defiant. Burning full loads of very dry wood, we'd control the heat by starving the fire of air. This resulted in incomplete combustion, creosote, and a chimney fire.
ecocavalier02
Minister of Fire
Backwoods Savage
Minister of Fire
wkpoor said:
That indeed could be part of the problem but not the whole solution.
btw, I agree that the stuff you describe is no hazard and could be considered normal....except not in the quantity you have it. The reduction and a leak somewhere do sound like the most likely. I hope you are able to trace this down.
NWfuel
Minister of Fire
What is your start up procedure. Are you getting a FAST CLEAN START? Using pitchy material at start up will cause build up in a cool pipe.
Thomas
Thomas
I think this is with your Nashua correct, I had my pipe reduced to 7 1/4 and I had a reducer plus a damper and I think no way is that causing that much of a problem, have you got the reducer as close to the chimney as possible so you have some 8 inch pipe?
Another thing with the old Nashua, dont worrry about the stove top unless it glows (rudolf's nose so bright) that stove is a made out of some 5/16 steel in some parts so let it rip, the fan would also help keep the stove top in check a little more, never had a stove top thermometer on mine in 30 years but I had the fan also.
Sorry Oldspark, I did not do a smoke test as I'm not sure what that is. My reducer is right next to the stove. It would have been a good idea to put it at the thimble. Also I do not have any butterfly damper in the pipe. As for how I load, I just put in wood n hot coals whenever and keep air set for 500 on stove top.oldspark said:
A smoke test is unsing a smoldering match, punk, or inscense stick to check for air being sucked in where it is not supposed to, my Nashua had about 5 ft of 8 inch pipe before reducer (not sure if that would help or not), I never ran mine with out the fan but like I say on those old stoves not a lot of people had thermometers on the stove top and I would run the flue around 300 at least and not worry about the stove top, that thing is built like a tank. In the origanal adds they put a stick of dynamite in one and it only broke the door latch.wkpoor said:
I just discovered what may be what I thought could be the problem. With an IR thermometer I measured reducer temp vs pipe temp. There is over 100 degree difference just 6" above the reducer and its get cooler from here on up. Thats were I'm loosing the heat and explains the cool pipe above.
Might be worth a try to put 8 inch up to the thimble, how much stove pipe do yu have, you did mention you have a new stove ready to go in?wkpoor said:
Rather than go through the stink of seasoning a new 8" pipe I'll wait a couple of days and just install the Magnolia. Its a 6" stove.
I gotta say cleaning that pipe sure made a difference today. Also I took your advise and just opened er up. Can use the heat today anyway. Its cold with a stiff wind blowing. Since I've opened it up today burn times are real short. I'm adding wood every hour to keep it hot.
I gotta say cleaning that pipe sure made a difference today. Also I took your advise and just opened er up. Can use the heat today anyway. Its cold with a stiff wind blowing. Since I've opened it up today burn times are real short. I'm adding wood every hour to keep it hot.
Sounds like a good idea (new stove install) what kind of wood are you burning and how hot has the stove top been getting?wkpoor said:
Before you take that Magnolia ( ! ) in ( BTW: what's a "Magnolia" stove ?), check your Nashua thoroughly.
An air leak is a good possibility, BUT. Try this: Most of the stoves from the 70's were engineered with either secondary air and/or complex flame/smoke paths to inscrease the amount of BTUs from the stove.
I don't know the Nashua, but the similar Fisher line had a bypass plate that would be used WHEN there was pyrolysis , or a good hot coaled fire.
Check that your Nashua's bypass (if there is one) is not in the closed position. Or,
Take the stove outside, blow the stove out with compressed air or a strong vac in reverse.
So, if the bypass plate(damper) or the internal flame path were blocked (ash, furnace cement, broken firebrick) the exhaust gases from even a hot fire would be cooled before the flue.
For air leaks, dealers have small "smoke bombs" to light in a stove with the flue and air blocked (don't use indoors).
Another appraoch to your creosote dilemma. Give it a try.
An air leak is a good possibility, BUT. Try this: Most of the stoves from the 70's were engineered with either secondary air and/or complex flame/smoke paths to inscrease the amount of BTUs from the stove.
I don't know the Nashua, but the similar Fisher line had a bypass plate that would be used WHEN there was pyrolysis , or a good hot coaled fire.
Check that your Nashua's bypass (if there is one) is not in the closed position. Or,
Take the stove outside, blow the stove out with compressed air or a strong vac in reverse.
So, if the bypass plate(damper) or the internal flame path were blocked (ash, furnace cement, broken firebrick) the exhaust gases from even a hot fire would be cooled before the flue.
For air leaks, dealers have small "smoke bombs" to light in a stove with the flue and air blocked (don't use indoors).
Another appraoch to your creosote dilemma. Give it a try.
A Magnolia is a cheap US Stove mfg commonly sold at TSC stores. No cat jut secondary burn. I did a thorough check of the Nashua before I brought in plus a real good cleaning with air house and leaf blower hehehehe. You are correct, the Nashua uses a clever smoke path deal before exiting the stove.fjord said:
fjod I have the same stove he has and no bypass, it has a simple baffle system that is hollow so air from the blower can go through it. 500 to 600 is nothing to worrry about then with the air turned up, what are the flue temps getting up too with more air?
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