Jotul F100 - QT - Backpuffing/Reverse Draft Question

[scottgen20]

Hi Everyone,

I installed a Jotul QT wood stove in the fall, with a stainless steel chimney liner.. My chimney is fieldstone, and only about 15ft high. I've been having problems with backpuffing at startup.. I've followed some advice that I found online - twisting together some newspaper and holding it up to the chimney opening to reverse the draft... That works, but here is my problem..

The Jotul QT has a large top baffle inside the stove which basically blocks the flue opening, except for a 1" opening which runs across the front edge of the stove (I believe that this is what achieves the glass airwash) If I remove the top baffle, I have direct access to the flue opening can light a newspaper directly at the opening - reversing the draft rather quickly. Here is my problem.. The top baffle is rather difficult to put back into place.. So it is a huge pain to remove it just to reverse draft, then reinstall it correctly before loading and trying to actually "start" the fire.

Here is my question.. Is it safe to operate the stove with the baffle removed? This would probably defeat the airwash feature, but I could probably deal with that, rather than having to remove/install the top plate each time I want to start a fire.

Any advice would be greatly appreciated!

Thanks,
Scott

 

[JAred]

without the baffle in place it might not burn as clean as it was meant to.

 

[Corie]

the top baffle as in the big piece of metal that sits directly above the secondary burn tubes?

that's a negative. Burn without that (if that is indeed what you're talking about) and you will not have much secondary combustion going on.

 

[scottgen20]

Ahh.. I see.. That's what I'm talking about.. Any ideas on how I can keep a positive draft without having to remove the plate in order to heat the flue?

Thanks!

 

[Mike Wilson]

Take 2 sheets of newspaper, roll them into 2 tubes. From the front of the stove, insert both tubes on top of the baffle plate, one tube on each side of the flue hole. The tubes should be lined up front to back (so you are looking into the tubes). Then light each tube. You will have instant draft, no smoke. Do not operate the stove without the baffle plate in place, it won't work right at all, and you'll void the warrantee.

-- Mike

 

[hawse]

I have the same problem on occasion and im lucky enough to have a window within arms length.As i see the smoke pour out the vent on the stove i open the window slightly and watch the smoke suck right back in,close the window open the ash pan or door very slightly and away you go.try that and you should be okay.

 

[Rob From Wisconsin]

Whatever you do, don't remove that baffle!!
By doing that, you are basically re-verting back to
an old, pre-EPA air-tight stove. It probably won't
support secondary combustion anymore, and you
could face the problem of true "backpuffing" that
occured frequently on those types of stoves - a
backwards explosion that occured because of insufficient
combustion air.

Rob

 

[jabush]

Not familiar with your stove but...do you have a cleanout door on your masonry chimney? before I had my chimney lined and directly hooked to the stove, I often had a hard time establishing a draft. The baffle on my stove also covers part of the outlet opening. I would go outside and warm the flu through the cleanout door and then run back in and start my fire. Worked fine but kind of a PITA.
Now...with the stainless liner I don't have a problem. It seems that once the steel feels the heat it takes right off.

hth,

joel

*edit* Rob...I've never had a backpuffing problem with my "old smoker" while burning. Even before the new liner.

 

[BrotherBart]

Like everyone has said, don't take out the baffle. You will end up with a thousand dollar five gallon can with a chimney attached. What you have isn't back puffing it is just smoke coming back out that isn't sucked up the chimney because draft isn't established.

The F100 in my office is on a chimney with lousy draft, until I get a chance to fix that this spring, and here is what I do to get it cranking.

1. Place five or six pieces of wadded up thick paper on the floor of the firebox.

2. Place your "tender", slivers of dry wood, on top.

3. Light the paper but do not close the doors compeletly. Leave it open a little bit. Closed to the point that the latch mechanism just contacts the front of the stove works for our stove. This is going to create an air path that comes across the glass, turns back into the kindling and moves from right to left across the firebox. If your kindling flame goes out toss a wadded piece of burning paper next to it on the riight side of the kindling to keep it going and return the door to the semi-closed position. The flame will be drawn right to left through the kindling.

4. When the kindling burn is established add a few small pieces of wood on top leaving openings for the air and flame to get through the pile.

5. Return the door to the semi-open position.

6. When this wood is burning really good add your bigger splits and repeat the open door process to get a burn established with them.

7. Close and latch the door and run at full open primary air until the stove is up to around 400 degees and adjust primary air as needed.

The primary air intake on the Nordic is just too restrictive to maintain a fire with poor draft and with poor draft no secondary air is pulled in through the secondary air channels.

May help, may not but it is the drill that gets this office warm every morning.

 

[scottgen20]

Thanks so much everyone for all of your advice! I'm going to try a couple of these and see what happens.. I installed the stove back in September, and used it up until the end of November, but then stopped using it until two days ago..

The reason that I stopped using the stove was the reverse draft, along with poor/smouldering burns. I'm new to wood stoves, so it could be that the wood which I had delivered in August just wasnt dry enough (even though I was told it was seasoned), along with my 15' chimney.. In addition, I lined the chimney with a stainless steel liner, but had to ovalize it to get it through the clay flue, and had to angle it into the firebox at a rather severe angle. (more ovalizing) The stove is sitting inside my fireplace opening.

In December, I pulled the stove, cleaned out the "T" (the stove was connected to the liner with a "T" fitting, and was vented out the back of the stove). When I peered up through the liner, I was amazed.. It was very very dirty for what was only about 2.5 months of use (and it's a very small stove). There was about 1/2 inch of hair-like buildup around the inside of the entire liner. I purchased a brush kit, and when I went up on to the roof to remove the cap, I found that all of the vent holes in the cap were clogged with what I suppose was creosote. I'm assuming just another result of poor burn/draft.

At any rate, last weekend, I pulled the stove out of my fireplace.. My fireplace firebox was lined with a heavy steel liner, which was causing me to have to angle the stainless wood stove liner up the chimney at a severe angle.. Since the fireplace is really in no shape to support a fire on its own, I took a metal saw and cut out the back of the firebox in order to reveal the original firebox, made of fieldstone. I was then able to push the stove back further in the opening and vent from the top of the stove instead of the rear, reducing the stress on the liner (now its a straight shot from the top of the stove up the chimney).

On Sunday, after removing the top baffle in the stove to access the flue opening, I was able to reverse the draft, put the baffle back in place, and acutally have a nice fire.

I still find that in order to get a really good burn, I need to leave the door on the stove cracked. Once it really gets going, I can close the door, but I don't really dare turn down the air control, as it will cause the fire to smoulder rather quickly.

Thanks to all for your advice!
Scott

 

[tutu_sue]

DON'T TOUCH THAT BAFFLE

I have a Jotul in the basement and a very strong negative draft with a cold stove/outside metal chimney. We have strong negative house pressure. First there was a ton of smoke in the room at startup. Very discouraging. Here's what I do now and no smoke.

Open air lever all the way

I put down twisted newspaper (burns slower than crumpled to ingnite kindling), two fatwood sticks and 1" kindling, then two 2" and 3" wood on top of that. Then on top of the kindling I put a fan folded (see pic below) against the back wall of the stove. The newpaper touches the baffle, but I'm sure not to let the paper or flames go past the front of the baffle so I push it way back (see pic below)

Then I crack a window a bit (you may not have to do this, but do so if you still get smoke)

Quickly light the top of the newspaper all along the edges of the paper to get it burning as quickly as possible. I use long fireplace matches. The trigger lighters alway go out on me and then won't relight.

Close door to about 3/4 inch until the paper is all burning and you see smoke going up

Open door and quickly light bottom papers only in the front

Close door to 3/4 inch until kindling catches fire

Close door all the way

Close window

If you still have smoke, then get one of those small double box fans about (10" high) and put in the window set to blow air in (reverse) before lighting. This gets rid of negative pressure in the room. Then once kindling is all burning, turn the fan off and close the window.

Let us know how you make out.

 

[CK-1]

Will a wood burning insert using outside air for combustion have this problem?.. If I where a gambling man, I would say this may occur when room air is used..

 

[the_guad]

I think that running without the baffles will also lost a significant amount of heat up the flue. Just don't do it. I've also heard of folks using small space heaters to heat up the interior of the stove without flames and smoke.

 

[Mike Wilson]

I think that running without the baffles will also lost a significant amount of heat up the flue. Just don't do it. I've also heard of folks using small space heaters to heat up the interior of the stove without flames and smoke.

Before I had my insert in the fireplace I would take a propane Coleman single burner camp stove and put it in the fireplace to get some draft quick. Worked well, didn't smell up the house either.

-- Mike