New Chimney stained in 3 days

[skowhegan]

Just installed an complete new 8inch triple wall Hart and Cooley Chimney, replaced old unit. Within 3 days the top of cap and 1 foot below cap (on pipe) has turned black, purple and a brown/orange color. The temp gauge on woodstove has never been in hot zone.

Is this normal? Should the cap be replaced?

Thanks in advance for your input.

 

[Woody Stover]

What stove? How tall is the chimney? When establishing a new load, do you run the air wide open? That is the only way I can imagine the top of the chimney getting discolored that quickly. Just because you aren't over-firing the stove (that you can see on a stove top meter) doesn't mean you aren't over-firing the chimney. I never want to see a roaring fire in the box. That said, you probably haven't hurt it, depending on how long you ran it wide open. I'm assuming you don't have a flue probe installed...

 

[begreen]

Could be creosote forming due to running the stove too cool or poorly seasoned wood. Post some pictures and a description of the stove and chimney cap if possible.

 

[DougA]

My ICC chimney did exactly the same thing last year when installed new. I posted about it and said that my old chimney was never that bad in 30 yrs of use. I assume that the SS they are using these days is a much cheaper grade. I got blasted for saying that. My old chimney was non magnetic, the new one is. That tells me it's a lower grade.

 

[quotejso]

What stove? How tall is the chimney? When establishing a new load, do you run the air wide open? That is the only way I can imagine the top of the chimney getting discolored that quickly. Just because you aren't over-firing the stove (that you can see on a stove top meter) doesn't mean you aren't over-firing the chimney. I never want to see a roaring fire in the box. That said, you probably haven't hurt it, depending on how long you ran it wide open. I'm assuming you don't have a flue probe installed...

Never a roaring fire? Why?

 

[Woody Stover]

Never a roaring fire? Why?

Even though your stove top meter is not reading high, you may be subjecting stove internals, especially the bypass area, to excessive heat. I saw the stainless tee glowing on my BIL's basement stove when he left the air open too far for too long. I've seen a faint glow on my tee as well, but won't admit that here. Maybe with a top-vent system, cooking the pipe is less of a problem, I don't know. Maybe tube vs. cat is something to be considered, or bypass vs non-bypass stoves. But I know that if you floor your car a lot, it won't last as long. I don't think it takes me too much longer to ramp up to temp, running the stove moderately. Lively flame is OK but I don't want a blast furnace in there. I might have the air wide open on a re-load but once flames start getting to the top of the box, I'm cutting air.

 

[Sawset]

Mine is the same way. The rainbow color at the top washes off come summer. The wood burned is dry, stack thermometer well within recomended limits, SS, class A.

www.hearth.com/talk/threads/little-help-why-is-my-stainless-smoke-pipe-discolored.56511/

 

[skowhegan]

only ha

What stove? How tall is the chimney? When establishing a new load, do you run the air wide open? That is the only way I can imagine the top of the chimney getting discolored that quickly. Just because you aren't over-firing the stove (that you can see on a stove top meter) doesn't mean you aren't over-firing the chimney. I never want to see a roaring fire in the box. That said, you probably haven't hurt it, depending on how long you ran it wide open. I'm assuming you don't have a flue probe installed...

Its only been kept open when starting and even then its temporary with just a few pieces of wood...the old chimney had no stains at all but was rusted inside and was about 30 yrs old, i was told the liner was buckled and looked like it had a chimney fire. thought it best to replace, like i said the discoloration started almost instantly (by the third fire). The stove is a fisher with a rear pipe, not the one on top. I think its referred to as the Momma Bear model. Thank you in advance for your advice, its much appreciated.

 

[begreen]

The old Fisher is not a clean burner unless modified with an added baffle and maybe a secondary manifold. I am going to move this over to the Fisher forum so that you get Fisher focused information.

PS: Could the pipe double-wall insulated? As far as I know Hart and Cooley only makes double-wall insulated chimney pipe.
http://www.hartandcooley.com/chimney-and-vent/all-fuel-class-a-chimney/tlc-chimney-system

 

[skowhegan]

Hart and Cooley says they will send a new cap, as of last week, i just have the feeling it has somethng to do with that...I also noticed this last snow storm that on the roof was alot of orange rusty colored spots of somthing from the chimney, laying on top of the snow (on roof) so im hoping that rain and or snow isnt getting into the chimney.

 

[skowhegan]

The old Fisher is not a clean burner unless modified with an added baffle and maybe a secondary manifold. I am going to move this over to the Fisher forum so that you get Fisher focused information.

PS: Could the pipe double-wall insulated? As far as I know Hart and Cooley only makes double-wall insulated chimney pipe.
http://www.hartandcooley.com/chimney-and-vent/all-fuel-class-a-chimney/tlc-chimney-system

I went to the plumbing supply they say its triple walled, maybe thats just the section that goes through the house wall into the garage? not sure. i will clarify that though this week.

 

[skowhegan]

The old Fisher is not a clean burner unless modified with an added baffle and maybe a secondary manifold. I am going to move this over to the Fisher forum so that you get Fisher focused information.

PS: Could the pipe double-wall insulated? As far as I know Hart and Cooley only makes double-wall insulated chimney pipe.
http://www.hartandcooley.com/chimney-and-vent/all-fuel-class-a-chimney/tlc-chimney-system

thanks

 

[coaly]

Just installed an complete new 8inch triple wall Hart and Cooley Chimney, replaced old unit. Within 3 days the top of cap and 1 foot below cap (on pipe) has turned black, purple and a brown/orange color. The temp gauge on woodstove has never been in hot zone.
Is this normal? Should the cap be replaced?
Thanks in advance for your input.

The temp gauge I'm assuming is a magnetic thermometer and would be calibrated for single wall connector pipe. The low, Creosote and Hot zones are for pipe temperature, not stove top.

Operating the stove without baffle with air dampers open more than a turn and a half can get the stack quite hot. That should be well over 600* stove top..... the red area on most stove pipe thermometers.

Starting the stove with cardboard and kindling can get the flue way hot near the top if you let it roar up the stack. I've found the best way to start your stove is to open both air dampers two turns or more. Light fire and when kindling roars up stack, close flue pipe damper slowly until roar stops. That usually gives you an idea where you will be running damper after it is up to temp as well. You can slow the fire by closing air intakes, but with a new fire, this is not the time to deprive it of oxygen. It will keep more heat in the stove to start larger pieces and reduce smoke at start up. As larger fuel catches, close air intakes to about 1 turn.
A temperature reading on the pipe, just before it enters the insulated chimney flue is where you want to monitor the temp. The object is to keep internal flue gas above 250* f all the way to the top. It's a guess as to how much it will cool before it exits flue, but your insulated flue stays hotter than masonry or uninsulated liner. Keep in mind you are measuring surface temperature, not internal flue gas which will be much hotter. 30 to 50% hotter than surface temp is average, even double the measured surface temp depending on velocity. 250* is the temperature to achieve in flue while smoke is present mid burn, not during the coaling stage when no smoke particles are present to create creosote.
Get your temps within range and you should see no discoloration. (except under cap since cool air blows on cap condensing vapor which allows smoke particles to stick creating creosote build up on cap)

 

[skowhegan]

The temp gauge I'm assuming is a magnetic thermometer and would be calibrated for single wall connector pipe. The low, Creosote and Hot zones are for pipe temperature, not stove top.

Operating the stove without baffle with air dampers open more than a turn and a half can get the stack quite hot. That should be well over 600* stove top..... the red area on most stove pipe thermometers.

Starting the stove with cardboard and kindling can get the flue way hot near the top if you let it roar up the stack. I've found the best way to start your stove is to open both air dampers two turns or more. Light fire and when kindling roars up stack, close flue pipe damper slowly until roar stops. That usually gives you an idea where you will be running damper after it is up to temp as well. You can slow the fire by closing air intakes, but with a new fire, this is not the time to deprive it of oxygen. It will keep more heat in the stove to start larger pieces and reduce smoke at start up. As larger fuel catches, close air intakes to about 1 turn.
A temperature reading on the pipe, just before it enters the insulated chimney flue is where you want to monitor the temp. The object is to keep internal flue gas above 250* f all the way to the top. It's a guess as to how much it will cool before it exits flue, but your insulated flue stays hotter than masonry or uninsulated liner. Keep in mind you are measuring surface temperature, not internal flue gas which will be much hotter. 30 to 50% hotter than surface temp is average, even double the measured surface temp depending on velocity. 250* is the temperature to achieve in flue while smoke is present mid burn, not during the coaling stage when no smoke particles are present to create creosote.
Get your temps within range and you should see no discoloration. (except under cap since cool air blows on cap condensing vapor which allows smoke particles to stick creating creosote build up on cap)

Thanks for the advice, i replaced an old chimney of 30 yrs age, in all the 16 yrs that i used that i never had any discoloration, it was replaced due to a chimney fire (prior to my purchase of the home, that i was unaware of until recently) and this new triple walled Hart and Cooley discolored in THREE DAYS ! It didnt even have time to get HOT...lol. I use small pieces of Rutland fire starters to get it going they start like magic
All input is appreciated.

 

[coaly]

It's not going to get hot if it's an 8 inch on a Mama Bear either. Not sure why you would buy a new 8 inch chimney for a 6 inch Mama when that's the time to get the right chimney. Unless you're measuring the outside of the chimney pipe or don't have a Mama Bear ??

 

[skowhegan]

It's not going to get hot if it's an 8 inch on a Mama Bear either. Not sure why you would buy a new 8 inch chimney for a 6 inch Mama when that's the time to get the right chimney. Unless you're measuring the outside of the chimney pipe or don't have a Mama Bear ??

maybe im mistaken then, its definitly a 8inch and the pipe is out the back, not the top. I thought if it was out the top that was a PaPa Bear? I'll try to take a picture and post it later on.

 

[coaly]

No, all older models were available side, rear or top vent. Position of vent does not change model, the size determines the model.
Mama and Papa are 6 inch, Mama takes 24 inch log, Papa 30 inch, they are both single door stoves of the Bear Series.
The full size double door stoves are 8 inch called the Fireplace Series.
Brick count across back will tell if it is a Grandma with 5 bricks, or Grandpa with 6.
The doors and if it has shields will further determine if it is a I, II, III. (or IV if it has glass doors)

The first post here will identify your stove;
https://www.hearth.com/talk/threads/everything-fisher.48309/

 

[skowhegan]

No, all older models were available side, rear or top vent. Position of vent does not change model, the size determines the model.
Mama and Papa are 6 inch, Mama takes 24 inch log, Papa 30 inch, they are both single door stoves of the Bear Series.
The full size double door stoves are 8 inch called the Fireplace Series.
Brick count across back will tell if it is a Grandma with 5 bricks, or Grandpa with 6.
The doors and if it has shields will further determine if it is a I, II, III. (or IV if it has glass doors)

The first post here will identify your stove;
https://www.hearth.com/talk/threads/everything-fisher.48309/

thank you for that information...im so excited im going to count the bricks now...lol...ive used this almost 20 yrs and didnt know any of this
Its a double door with 8 inch pipe and 5 bricks. What are you meaning when you say the "shields"?

 

[skowhegan]

My ICC chimney did exactly the same thing last year when installed new. I posted about it and said that my old chimney was never that bad in 30 yrs of use. I assume that the SS they are using these days is a much cheaper grade. I got blasted for saying that. My old chimney was non magnetic, the new one is. That tells me it's a lower grade.

This is what i was thinking also...because the old one i used for over 17 yrs never turned any other color then what it originally was. And every specification is exactly the same.

 

[coaly]

thank you for that information...im so excited im going to count the bricks now...lol...ive used this almost 20 yrs and didnt know any of this
Its a double door with 8 inch pipe and 5 bricks. What are you meaning when you say the "shields"?

Your stove is a Grandma I IF it has flat top doors. It is a Grandma III IF it has arched top doors.
It's not as simple as that, so pictures all the way around are sometimes needed.

1976 was the first year for double door stoves. They had no shields which are added steel sheets to the rear and bottom. Stoves with no shields having old style flat top doors would be a Roman Numeral I.

Drawing revisions were sent to the licensed fabricators as improvements were made, and 1977 drawings included optional bolt on shields (added sheets to drawings specified 20 GA Cold Rolled Steel) for installation on other than non-combustible fireplace hearths. These were designated Model II on the prints in 1977, the Roman II was used internally company wide, but the designation was not used in advertising, brochures or marked on stoves.

1979 started optional "Cathedral" arched top doors that became the only style available after 1980 to the end of production. Flat and Cathedral co existed this year only becoming the Model III.

1980 started the redesigned one piece, bent corner box that was still designated III. All the new style boxes had welded shields and were UL listed. They also had Smoke Shelf Baffles to reduce smoke particulate. Only double door stoves of the Fireplace Series were designated III. Later glass double doors were IV and had rear shield bolted on with optional blower under shield at rear. All single door stoves of the Bear Series went from II to VI. Stoves like the Coal Bear, Honey Bear, Teddy and Goldilocks (no Roman Numerals) had double shields welded in place for close clearance.

What makes it complicated is most fabricators continued to offer stoves fabricated in the first design with angle iron corners long after 1980 when only arched top doors were available. They were $100 cheaper for those installed on non-combustible hearths or cement floor basements and were not UL approved. That was not necessary until years later as laws changed. Below Grandma III front and back with shields compared to the old style box with Cathedral doors difficult to date with no UL tag.

1980 to '88 designated III.

Old style box with pre 1980 flat top doors. NOT UL Approved.
They WERE tested by other labs, but UL was not the recognized standard yet.

Old style box after 1980 with Cathedral doors.
This one was fitted with shields so it does have UL tag attached to rear shield;