fisher wood stove smoking too much!

[woodcuter ms361]

hi all!

i just bought an old fisher grandma bear, or grandpa bear (not sure which, but i'm pretty sure it's the grandpa). it has the 2 doors on the front, and an 8" flu outlet on the back.

i cannot for the life of me, get this thing to draft all that well. i had an ashley before the fisher and it would do the same thing.

the "thimble" that goes through my wall is a 6", so i put a 8" to 6" reducer to accept the larger fisher.

my stove's in my basement, and i've tried everything imaginable as far as opening a door, opening 2 doors, cracking one door, cracking both doors, i've even extended my chimney another liner length ( back when i had the ashley).

any suggestions are VERY welcome!

 

[PA Plumber]

The "experts" might show up, but I'll give it a shot...

I'm sure you've checked: Clean flue/no obstructions? How long vertical stack? How long Horizontal to vertical? Chimney cap? If so, is the cap clean? Does the chimney have a liner in it? What size/diameter is the vertical stack? Any trees near the home? Does the chimney terminate above the roof line?

I don't think it's a good idea to go smaller on the flue. If 8" is out the back of the stove, I believe the flue all the way up should be 8". If it's just the thimble, it's probably less likely to be an issue if the vertical run is oversized.

 

[SpencerS]

yes, the flu is as clean as a whistle, and i'm lead to believe my chimney is plenty tall. i think i'm gonna try the 8" pipe. any other suggestions?

 

[danrclem]

It sounds like you have the Grandpa Bear which is what I have except that mine vents from the top of the stove. I have necked mine down to 6" and it vents good except when the chimney starts getting stopped up.

I would think that your problem is in the chimney system since your other stove did the same thing.

 

[brownbuttlover]

i think ur chimney needs to be taller, an ur running threw the wall

 

[WetBehindtheEar]

You present a question with some - but not quite enough- information for those of us (definitely NOT me) who have a more professional opinion.

I agree with the others on a blockage - in the spirit of fun, I'll bet on a raccoon's nest in the chimney.

You say you added on an additional length of stove pipe @ the top - do you have a cap on it?

As others have said, it's generally a bad idea to 'neck down' an 8" pipe to a 6" but if your stack height is long enough, it can make up for that lack of volume with higher velocity.

It may be worthwhile to have a stove & chimney installer out to test the draft of your system.

I've got a 40+ foot run from the basement to the top of my chimney so I could probably neck down an 8" to a 6" but with a more modern stove it wouldn't be necessary.

If you've been burning, in your words, 'smoky' fires. Maybe you've got some serious creosote buildup going on.

Good luck and let us know what you find!

 

[SpencerS]

this is the owner of the stove with the problems talkin! i was logged in under my dad's account when i made the post.

the chimney is definitely NOT stopped up. i have a clean out door at the bottom of my chimney, and i laid a mirror in there and shined a light up through it and it was nearly spotless! my chimney is only 1.5 years old.

i'm not exactly sure how tall my chimney is, but i'd say it's probably 20 or more foot from where it comes out of the wall and goes into the stack.

i do not have any kind of rain guard either. it's totally open for santa to stop by this year lol.

hope this gives a little more info for everybody!

 

[KsWoodsMan]

I'd put my 2 cents on - is the flue or liner insulated ? or uninsulated and exposed to the elements (cold) outside the house ? For it to draft it has to get hot and stay hot all the way to the top.

Is it a long horizontal run from the stove to the thimble ? or not enough rise over run in the horizontal section ?

Green wood maybe ?

Is there another appliance connected to the flue ?


I'm out of ideas real quick , sorry.

 

[PA Plumber]

this is the owner of the stove with the problems talkin! i was logged in under my dad's account when i made the post.

the chimney is definitely NOT stopped up. i have a clean out door at the bottom of my chimney, and i laid a mirror in there and shined a light up through it and it was nearly spotless! my chimney is only 1.5 years old.

i'm not exactly sure how tall my chimney is, but i'd say it's probably 20 or more foot from where it comes out of the wall and goes into the stack.

i do not have any kind of rain guard either. it's totally open for santa to stop by this year lol.

hope this gives a little more info for everybody!

Up 20'
What diameter, dimensions is the chimney?

Making some assumption here:
How long is the run from the stove up to the 90 that heads to the thimble?
How long is the run from the at the top of the stove to the thimble?

Or:
Does the stove pipe leave the back of the stove, 90 up to the level of the thimble and the 90 to the thimble?

Or:
Did you reduce right off the back of the stove, then use 6" the rest of the way to the thimble?

Whew, some pics would sure help here...

 

[timberdollars]

fisher smoke

I have a Fisher Grandpa bear, 8" outlet on top, mine in reduced to 6" about 40" above the stove then makes a 90 degree turn into my chimney. My house is very old and my chimney get stopped up every month or so, the chimneys to cold!!!
But does your stove have the baffle inside? Mine is newer and had one but I replaced it and made it larger to be more efficient (BAD IDEA) smoked badly, to much creosote. I put it back to OEM size works fine.
I can tell you these do not like 6", you need to taper your reducer (custom made) so the top of the pipe is flat to your chimney. You can not have dead air in the pipe. I'm sure if you make the taper reducer or something it will fix your problem. The pipe going to your chimney must be flat across the top. You need as much 8" as possible, I had a 8-6 reducer right at the stove outlet and it smoked out the doors bad, i changed to my current setup and most is gone.
Grandpa bear is 150,000 btus or close

 

[stumpy75]

Although I suspect the problem is the 8" to 6" reduction, do you have any trees near the chimney? A thread a while ago on here mentioned the problems with drafts as trees grew around the house and changed the airflow. Just a thought...

 

[SpencerS]

i was going to post pictures, but i'm having problems uploading them! any one know what's going on? is there a size limit of the pictures?

 

[Shmudda]

I have a Fisher Grandpa bear, 8" outlet on top, mine in reduced to 6" about 40" above the stove then makes a 90 degree turn into my chimney. My house is very old and my chimney get stopped up every month or so, the chimneys to cold!!!
But does your stove have the baffle inside? Mine is newer and had one but I replaced it and made it larger to be more efficient (BAD IDEA) smoked badly, to much creosote. I put it back to OEM size works fine.
I can tell you these do not like 6", you need to taper your reducer (custom made) so the top of the pipe is flat to your chimney. You can not have dead air in the pipe. I'm sure if you make the taper reducer or something it will fix your problem. The pipe going to your chimney must be flat across the top. You need as much 8" as possible, I had a 8-6 reducer right at the stove outlet and it smoked out the doors bad, i changed to my current setup and most is gone.
Grandpa bear is 150,000 btus or close

Timber,

Where in the world did you get this heat output for this stove? These old Fishers, while great stoves never were that efficent to begin with, let alone to put out BTU's like this. You don't get into this BTU range until you get into a wood furnace (indoor or outdoor) units. My grandfather had this stove, and my Mom still has it today, and I can attest that it's not producing 150K BTU's of heat......

Let me know your source please as I am very courious.........

Thanks,

Craig

 

[betterbuilt]

i was going to post pictures, but i'm having problems uploading them! any one know what's going on? is there a size limit of the pictures?

Try using

Web Resizer - Making Photos Faster - Optimize pictures for websites and email

 

[SpencerS]

i think i figured out the picture thing! hahaha here's some photos of my stove and chimney.
View attachment 206094View attachment 206095View attachment 206096View attachment 206097

 

[SpencerS]

You are to close to combustables with that chimney pipe.

what are you referring to as "combustables"? the trees?

 

[Richard C]

Spencer, That chimney looks like the ID is more than 6". If the chimney is larger and your entry is where the restriction is I would make the correction to 8". With that much draft, I saw the picture you posted, that Fisher should drive you out of the house. Good luck with it.


Richard

 

[KsWoodsMan]

I'd put my 2 cents on - is the flue or liner insulated ? or uninsulated and exposed to the elements (cold) outside the house ? For it to draft it has to get hot and stay hot all the way to the top.

snip

I'mma raise that 2 cents to a dollar fourty that it is a cold flue causing low draft..

Not much room for an air gap between the tile liner and the outside bricks.

 

[timberdollars]

Fisher ignition!!!!!

Sorry but this is not going to work!!!! I have that stove and it WILL!!!! ignite that pegboard!!!! these are 150,000 btu and you need 36" of clearance that is no joke!!!
I have metal roof behind my stove that is 20" away with a 3" air gap behind it before sheetrock, going all the way up to the pipe elbow like yours, it gets to 490 degrees!!!
You need to punch a hole through the cinder blocks going strait back or use all 8" up to the top elbow, the stove is rated for "1" elbow only, your reducer is lowering you smoke shelf height by 2"
My stove is the same one but I used 8" all the way to the top elbow, install a cleanout "T" behind the stove to clean it also, it can be adjusted to help draft also just make sure you can shut it down incase of fire.

 

[SpencerS]

thanks everyone! today i went and bought some 8" pipe and moved my reducer up to the very top just before it enters the thimble and that helped out TREMENDOUSLY! i think i'm gonna bring in a mason to change my thimble from a 6" to a 8" that way i'll have 8" all the way to the top of the chimney.

as far as the clearance to my wall goes, you can go over there and put your hand on that pegboard, and it's barely warm at all. i keep my stove damped down a lot because this place is pretty small. i mainly wanted the big stove so i wouldn't have to cut my wood so small (the ashley i had before this fisher taught me a lesson LOL), not because i need to use it's full heating capacity to heat my place.