Woodland F20 Baffle

[glenlloyd]

Hey all
I recognize that this is the Fisher stove section but when I have searched for 'making a baffle' it always leads me here because Coaly seems to be the expert on this topic and he's also a Fisher mod etc.

I recently purchased a Woodland F20 rear vent that had been sitting idle for many years, but it (amazingly) came intact with all the bricks and the front screen. Knowing that these old stoves don't have baffles I returned to the baffle thread and began figuring out how to add a baffle to this stove. The problem is that this morning while I was cleaning it out I went to see if there was a shelf at the back just below the vent and to my surprise the vent extends into the box 11". And further, there's a piece of sheet metal (like a saddle) on the bottom half of the vent that has a wire over the top holding it in place.

I'm not sure what the 'saddle' contributes but it projects barely 1/2" further forward than the vent itself, so why it's there I do not know. And further, this complicates the baffle design because the vent extends into the box so far. Is that 'saddle' supposed to be a baffle?

I will add pics of the mess so you all can see what I'm talking about. And if this content isn't allowed in the Fisher section please accept my apology. I only started here because of the topic and because the Woodlands are Fisher 'copies'.

Thanks
Steve A

edit: add pics

 

[coaly]

When air comes in one side or front, and goes out the other it has very little resistance to flow, so there is greater heat loss. Hence the baffle to change direction of flow slowing the velocity through firebox as well.

A stove such as an Upland with air intake on the left side and outlet in the center has a sliding baffle plate made of two pieces. When plates are separated in the center it allows exhaust straight up for use as a fireplace. When closing the front door, using as a radiant stove, you slide both plates to the left over the intake and exhaust outlet. This is an example of a reverse burn stove, also called a cigar burn since the burning logs have to burn towards the air flow coming in. That‘s what you have. Lighting it toward the back, behind the outlet makes it burn forward towards incoming air. A baffle in yours prevents the heat from rising to the stove top. It creates stagnet air flow above it.
Depending on draft, you could try an elbow on outlet pipe end facing downward so more heat rises above the opening. Think of the burning logs being a faucet. Now turn the firebox upside down in your head, and imagine the water filling up the “bottom” to the height of the “drain” which is the outlet pipe. You don’t want the water flowing directly out, keep it in the stove as deep as possible. With the outlet pipe facing downward you may be able to add a flat plate that hangs on J-bolts like a Honey Bear. It won’t have a direct opening upward, the heat has to enter from the open sides, turn upward, then horizontal across the outlet pipe. That’s the type of baffle I would add. This all depends on draft created by the chimney. A poorly drafting chimney won’t allow more resistance, so if you normally use a flue damper you can add more resistance in the firebox. Make sure the square inch opening around the pipe end is equal to the square inch area of chimney. It doesn’t take much since you will multiply the opening height X circumference. Hang on threaded J bolts allows height adjustment. Lower it for larger opening to allow more heat out for larger chimney or higher resistance due to connector pipe configuration. 3 J-bolts is fine.

 

[glenlloyd]

When air comes in one side or front, and goes out the other it has very little resistance to flow, so there is greater heat loss. Hence the baffle to change direction of flow slowing the velocity through firebox as well.

A stove such as an Upland with air intake on the left side and outlet in the center has a sliding baffle plate made of two pieces. When plates are separated in the center it allows exhaust straight up for use as a fireplace. When closing the front door, using as a radiant stove, you slide both plates to the left over the intake and exhaust outlet. This is an example of a reverse burn stove, also called a cigar burn since the burning logs have to burn towards the air flow coming in. That‘s what you have. Lighting it toward the back, behind the outlet makes it burn forward towards incoming air. A baffle in yours prevents the heat from rising to the stove top. It creates stagnet air flow above it.
Depending on draft, you could try an elbow on outlet pipe end facing downward so more heat rises above the opening. Think of the burning logs being a faucet. Now turn the firebox upside down in your head, and imagine the water filling up the “bottom” to the height of the “drain” which is the outlet pipe. You don’t want the water flowing directly out, keep it in the stove as deep as possible. With the outlet pipe facing downward you may be able to add a flat plate that hangs on J-bolts like a Honey Bear. It won’t have a direct opening upward, the heat has to enter from the open sides, turn upward, then horizontal across the outlet pipe. That’s the type of baffle I would add. This all depends on draft created by the chimney. A poorly drafting chimney won’t allow more resistance, so if you normally use a flue damper you can add more resistance in the firebox. Make sure the square inch opening around the pipe end is equal to the square inch area of chimney. It doesn’t take much since you will multiply the opening height X circumference. Hang on threaded J bolts allows height adjustment. Lower it for larger opening to allow more heat out for larger chimney or higher resistance due to connector pipe configuration. 3 J-bolts is fine.

Thank you for the suggestions, it makes sense with the long rear vent and the amount inside the firebox.

It makes me wonder whether or not it would be better to take this stove to a shop and have the rear vent converted to a top vent?

I think it would make more sense depending on what the cost to convert would be.

Steve

 

[coaly]

Rear vent was made for hearth installation in front of a fireplace, or through the wall installation with exterior chimney.

Top vent is for straight up installation. Depends on your needs.

 

[glenlloyd]

Rear vent was made for hearth installation in front of a fireplace, or through the wall installation with exterior chimney.

Top vent is for straight up installation. Depends on your needs.

That's what I assumed. Since this originally came from a farmhouse basement in Iowa I assumed it needed the rear vent to have a direct shot into the brick chimney

I acquired a junky old Blaze King KTJ302 recently, to use as a yard stove out on the brick patio, and the rear vent has been relocated to the top left corner.

Steve