Jotul F55 20ft flue Excessive Draft

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Trunkinator

New Member
Dec 27, 2020
21
Ohio
Hi Y'all, really hoping someone can help me..

So I've been on this forum before, trying to resolve my draft issue, and I've made some investigative progress...

I have a jotul f55 installed in the basement, goes up 2ft single wall to a 90, then into the brick external chimney to double wall insulated pipe, another 90 and upward 20ft.

I had my draft tested finally;

about 25deg outside, breezy
With air control totally open and a pretty good fire rolling, draft measure 11-12 (im guessing 0.11-0.12?) the technician was saying "eleven-twelve") and with my air control totally closed, was about 5-7. I've read and been told i don't want any more than 3 with it closed down.
Technician suggested a barometric damper, so he installed it and it made a great difference.
Later that evening, i was burning and my flue remained very cool (<250 18" above stove) and i began to research, and it sounds like these barometric dampers are a NO-NO for wood stoves??? Did I hire some jackoff to do my stove??? He was certified and licensed!!
I've read they can cause excessive creasote buildup as well as be detrimental during a chimney fire!!!

How can I better control my draft/fire in this stove?

on the bottom of the stove, if I close air control "totally", there are two 1/4+ inch gaps remaining on the "sliding gate" and there is a half inch drilled hole that is non adjustable. If i use my finger to plug the hole, i have great control of the fire then.
Would i void any warranty or cause legal issues if i somehow block the hole? Maybe with a heat rated magnet?

I'm getting 3 hour burn times on a full load and it turns into a blast furnace without the barometric damper, but the damper seems like a safety hazard! Help!

the video is the stove WITHOUT the barometric damper, with the air control totally down and a 2/3 full load of seasoned ash...

thanks I'm advance!

Matt
 

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Sailrmike

Feeling the Heat
Sep 20, 2017
278
06371
Hi Y'all, really hoping someone can help me..

So I've been on this forum before, trying to resolve my draft issue, and I've made some investigative progress...

I have a jotul f55 installed in the basement, goes up 2ft single wall to a 90, then into the brick external chimney to double wall insulated pipe, another 90 and upward 20ft.

I had my draft tested finally;

about 25deg outside, breezy
With air control totally open and a pretty good fire rolling, draft measure 11-12 (im guessing 0.11-0.12?) the technician was saying "eleven-twelve") and with my air control totally closed, was about 5-7. I've read and been told i don't want any more than 3 with it closed down.
Technician suggested a barometric damper, so he installed it and it made a great difference.
Later that evening, i was burning and my flue remained very cool (<250 18" above stove) and i began to research, and it sounds like these barometric dampers are a NO-NO for wood stoves??? Did I hire some jackoff to do my stove??? He was certified and licensed!!
I've read they can cause excessive creasote buildup as well as be detrimental during a chimney fire!!!

How can I better control my draft/fire in this stove?

on the bottom of the stove, if I close air control "totally", there are two 1/4+ inch gaps remaining on the "sliding gate" and there is a half inch drilled hole that is non adjustable. If i use my finger to plug the hole, i have great control of the fire then.
Would i void any warranty or cause legal issues if i somehow block the hole? Maybe with a heat rated magnet?

I'm getting 3 hour burn times on a full load and it turns into a blast furnace without the barometric damper, but the damper seems like a safety hazard! Help!

the video is the stove WITHOUT the barometric damper, with the air control totally down and a 2/3 full load of seasoned ash...

thanks I'm advance!

Matt
Wow that is certainly not "lazy" flames... is this the v2 f55? My v1 only had one of the 1/4" gaps you mentioned, and no hole.
 

Todd

Minister of Fire
Nov 19, 2005
9,413
NW Wisconsin
Are those internal or external flue temps? What were the temps like before the damper install?
 

john26

Minister of Fire
Oct 27, 2008
566
Wildwood MO
Could a manual key damper be installed?
 
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kennyp2339

Minister of Fire
Feb 16, 2014
5,974
07462
.05WC is the sweet spot on these stoves while running on high, since your double that a key damper would probably help slow things down, I know it made a huge difference for my setup and I was running a .18wc (3 times the recommended draft)
You already know a baro damper is not meant for wood burning, it just lets in to much cool air, I think there was only like one member here that installed a baro damper and had claimed success with a clean flu after running several weeks with it, but I think thats an anomaly
 

john26

Minister of Fire
Oct 27, 2008
566
Wildwood MO
I remember 1 maybe 2 guys with barometric dampers and a clean chimney but I think they had Kuuma high efficiency furnaces this was a big discussion about a month ago.
 

Todd

Minister of Fire
Nov 19, 2005
9,413
NW Wisconsin
There's plenty of people here who have tinkered with the air including me. I cant say if it would mess with your warranty or if its even legal or not. If it were me I'd get rid of the baro dampner and would probably would experiment with that fixed hole a bit or just install a regular pipe dampner.
 

MR. GLO

Member
Jan 26, 2021
136
Massachusetts
The f55 Manual Reads...Optimum draft force should be in the .05 - .10 in. w.c. range measured by a Magnahelic gauge. Draft at .07 w.c. is ideal. Excessive chimney height can promote over-strong draft resulting in high stove temperatures and short burn times. Excessive draft can be corrected by installing a butterfly damper.

One problems is my draft will go to .12 at full burn then drop to .08 on some days..etc...so you might need to play with damper all the time. But I would install a draft gauge first and a damper. Im still learning and testing. my burn times are bad sometimes too....I waiting on installing damper and new cap.

Today it slight rain and 30 degrees and my draft at no burn/empty stove was 0 but yesterday .04...

Where did you guy measure the draft from and what tool? Did he make a hole in the pipe?
 

Trunkinator

New Member
Dec 27, 2020
21
Ohio
The f55 Manual Reads...Optimum draft force should be in the .05 - .10 in. w.c. range measured by a Magnahelic gauge. Draft at .07 w.c. is ideal. Excessive chimney height can promote over-strong draft resulting in high stove temperatures and short burn times. Excessive draft can be corrected by installing a butterfly damper.

One problems is my draft will go to .12 at full burn then drop to .08 on some days..etc...so you might need to play with damper all the time. But I would install a draft gauge first and a damper. Im still learning and testing. my burn times are bad sometimes too....I waiting on installing damper and new cap.

Today it slight rain and 30 degrees and my draft at no burn/empty stove was 0 but yesterday .04...

Where did you guy measure the draft from and what tool? Did he make a hole in the pipe?
Yeah, he drilled a small hole and put the draft guage in a level surface. I guess my biggest issue now is maintaining the secondary burn. I can not have secondary burn without ripping lower flames