Going through too much wood

[Kimmy]

I have a double door Fisher wood burning stove. Seems like we are putting wood in it every hour to keep it going good. If we close the flue too much, then house gets filled with smoke. What can we do to make this stove more efficient?
Thanks!

 

[claydogg84]

Where is the smoke coming from when you close the damper? I'm going to assume you're not completely closing it, correct? This is an old stove and there is no way to make it more efficient, but you shouldn't be getting smoke back into the house when dampening it down.

 

[coaly]

Welcome to the Forum;
First, there ARE ways of making your stove more efficient. (starting with the chimney) Connected to the proper size chimney with correct connector pipe, seasoned wood, and baffle if not already installed will give you 8 to 10 hour burns between reloads.
What model do you have?
Top or rear vent stove?
What type chimney and flue size? (to the top)
What species wood and how is it seasoned?
Pictures of stove and connecting pipe as well as chimney will help.

Like claydogg stated above, you should not get any smoke inside. This can be caused by many factors including operator error. How far do you close damper before smoke comes in? I assume it leaks in at pipe joints?
Is the smoke inside when you use a screen during open door burning in Fireplace Mode?

 

[bholler]

Yes i totally agree with coaly you can make it more efficient. It will never be really efficient and it will always use allot of wood but it should never smoke into the house. And like he said you should be able to get 8 to 10 hours out of a load. Post some pics and tell us more about your setup.

 

[claydogg84]

You can't make the stove more efficient than it was designed to be. If you're using the wrong sized chimney, or bad fuel, than yes - You can improve its efficiency by fixing those things. These old stoves were not necessarily built with "efficiency" in mind. Coaly is very knowledgeable on this topic, you're in good hands.

 

[venator260]

Just a quick thought... are you closing down the air supply before you close the damper?

You should shut down the air before closing the damper, and open the damper fully before you allow additional air into the stove (either by opening air vents or opening the doors).

 

[bholler]

You can't make the stove more efficient than it was designed to be.

Again yes you can with a simple baffle you can increase the efficiency. As well as the other things mentioned

 

[claydogg84]

Again yes you can with a simple baffle you can increase the efficiency. As well as the other things mentioned

The other things mentioned shouldn't be considered improvements as its how the stove should be run regardless. I'm not quite sure what you're referring to about the baffle though.

Edit - I checked out coalys baffle idea and am intrigued. Seems like a relatively easy improvement.

 

[bholler]

The other things mentioned shouldn't be considered improvements as its how the stove should be run regardless. I'm not quite sure what you're referring to about the baffle though.

Edit - I checked out coalys baffle idea and am intrigued. Seems like a relatively easy improvement.

well they would still be an improvement in his setup regardless. Yes a baffle is an easy upgrade to do and it actually will do quite a bit

 

[claydogg84]

well they would still be an improvement in his setup regardless. Yes a baffle is an easy upgrade to do and it actually will do quite a bit

We don't know anything the OP's current chimney/wood situation so it's all speculation right now. It honestly sounded more like a learning curve problem, but the baffle may be a nice addition.

 

[Kimmy]

Where is the smoke coming from when you close the damper? I'm going to assume you're not completely closing it, correct? This is an old stove and there is no way to make it more efficient, but you shouldn't be getting smoke back into the house when dampening it down.

Hi, thanks so much for replying. I really guess I don't know if I'm even burning correctly. If I close the damper too much, then smoke builds up in the stove. Correct, I'm not completely closing it and I have two knobs on the front that I have open a bit as well. How many inches should the damper be opened? Thank you!

 

[Kimmy]

Welcome to the Forum;
First, there ARE ways of making your stove more efficient. (starting with the chimney) Connected to the proper size chimney with correct connector pipe, seasoned wood, and baffle if not already installed will give you 8 to 10 hour burns between reloads.
What model do you have?
Top or rear vent stove?
What type chimney and flue size? (to the top)
What species wood and how is it seasoned?
Pictures of stove and connecting pipe as well as chimney will help.

Like claydogg stated above, you should not get any smoke inside. This can be caused by many factors including operator error. How far do you close damper before smoke comes in? I assume it leaks in at pipe joints?
Is the smoke inside when you use a screen during open door burning in Fireplace Mode?

Hi Coaly and others that replied. I think I maybe need to start with 101 woodburning stove and burning, as I have no idea what any of these questions mean. ? for connector pipe Yes, seasoned wood, I do know that part ?baffle? ? for Model, but see pictures I took here. ? for top or rear vent? ? for chimney- I'm assuming it is brick and have no idea about the flue size. Is the flue and damper the same thing? ? don't know what type of wood, probably whatever grows in the Pacific NW and it's been under tarp for years. Only once I've used the screen just for looks, but if I remember correctly, I obviously keep the flue open just a bit when using the screen, but normally I only use the doors closed. Once, the fire is really going, it's great and heats wonderfully, but have to put a log on every hour or so. Sorry, I tried to upload 2 pics, but said it was too big for file on here? Any other way to send a picture?

 

[coaly]

You can send your pictures to [email protected]

That will tell me what model stove you have. Then I can direct you to the proper manual that will help a lot.

If you start with the Everything Fisher thread, (at top of Fisher Forum index page in sticky section) the first post should identify your stove. That was my idea to start the forum since many people didn't know what stove they had.

There are double door stoves with 6 or 8 inch outlets. That is where smoke exits the stove and it can be on top or rear. That is what top or rear vent means.
Depending on the model you have, you may already have a baffle plate inside the stove. Don't worry about that yet.

When I know the model, I will know what size chimney flue you need. The flue is the inner pipe or lining inside the chimney that the heat and smoke travels up through.
Connector pipe is the metal pipe that goes from stove to chimney.
The damper is a plate like a flapper inside the connector pipe. It should be close to the stove in easy reach. Not all chimney systems have them.

The most important thing to learn is that the chimney is the most important and the chimney is what makes the stove work.

Rising hot gasses in the exhaust are lighter than colder outside air. (outside of the flue) This temperature difference is what makes the exhaust rise up the chimney flue. This is called draft. This causes a low pressure area in the stove, like a vacuum.

Atmospheric air pressure pushes into the stove to fill the void created by chimney. This air feeds the fire oxygen to make it go.

The damper in the pipe is used to slow the chimney or reduce draft IF you have too much draft.
No one can tell you where to set it, since there are many factors and every chimney and vent system is different. It even changes with temperature and weather as in low pressure areas moving over your house. The lower the atmospheric air pressure, the less push you have going into stove. So it would need to be open more to increase the rising gasses or increase draft.
That is the basics of what makes it work.

Your area I believe is soft woods. Is the wood you have from trees that stay green all year?? Does it sizzle in the stove or do you see any liquid come out the ends like it's boiling?

When I know what wood and stove model, I'll be able to give you lighting and burning instructions, but you need to understand the basics first. (and read the correct manual)

Don't expect to learn how to operate it correctly overnight. You will learn new things about it after using it for years !

 

[coaly]

Kimmy has a full size "Fisher Fireplace Insert". Burning Fir that was cut and stored a couple years.

Here is the manual for your Insert.
https://www.hearth.com/images/uploads/fishinsertmanual.pdf
(The pdf pages were uploaded backwards, so start with the last page (17) which is the cover) You should print it and put in order so you have a hard copy.
Notice on page 5, there is a cut away showing installation in a fireplace. This was the original intent to use the existing fireplace flue. This proved to create creosote since many fireplace flues were very large for open fires and required more heat than the Insert could leave up. Below 250* water vapor condenses on the flue walls. Smoke particle stick and form a flammable coating called creosote. For this reason, it is no longer an accepted practice to install any Insert without connecting to an inner liner which will be a metal pipe inside the original fireplace flue. You should make sure your Insert is connected properly by removing the upper front cover plate. Look toward the back and make sure there is a pipe coming out of the top of the Insert. This pipe must go all the way to the top of chimney flue. Some are solid pipe sections like silver stove pipe (stainless steel) and others are a flexible long tube like a slinky that goes up the chimney. If there is no liner connected to the top of Insert you will need to install or have one installed.
Here is what your Insert looks like on the top when it was new and vented up the chimney with no pipe connection;

The rod across top is connected to the damper which is the flapper in the outlet. The insert is the only Fisher heating appliance made with factory installed damper. It does have a flat spot on it so it can't close fully.

Below is one way to connect the Insert to a liner. It's called a "Boot" and you would be able to see if something like this is mounted on top and connected to a liner that may look like a tube going up.

Another advantage for the direct connection to the liner is when cleaning, all soot and creosote will drop into the Insert. Without being connected, the entire Insert must be removed after cleaning flue to remove all the debris that falls behind it.

The reason you're going through so much wood is the wood species you have and not having hard woods in your area. There is so much difference between soft and hard wood that here on the East Coast since we have both, it is considered by most that soft woods should never be burned in a wood stove. That is false, the Fisher Stove was the first "air tight" stove invented in Oregon for burning Fir. The Fir trees on your doors had a special significance to the builder. If you can get hard wood such as oak or hickory you will find it burns much slower and will easily last all night. I've been told by some in the Northwest, the only oak they can get is from wood pallets when something is shipped from the East !

 

[TattedActuary]

I'm new here and hoping it's kosher to tag along on a thread that seems related to my question.

I recently purchased a home built in the 60's that has this same Fisher insert. Being a newbie to wood burning, I got a professional to come inspect and clean the chimney and stove. He remarked that I had a great stove to work with. I looked through the manual but still find myself having a few questions that (it appears) Coaly will undoubtedly know the answer to without even having to think too hard

1. The damper control lever - for the damper to be all the way open, the lever should be pushed all the way in, right? Also, when I pull the lever out, it' feels "springy" as I reach the limits of what I can pull. Is this normal?
2. I feel like I don't get enough air to the fire when I keep the doors closed. This is with both draft controls and the damper all the way open (assuming damper lever in = damper fully open). Thoughts?
3. Just in general for fire building. Assuming I'm using dry, seasoned wood (which has become a source of frustration as I've purchased from 3 different individuals now who claim to have dry, seasoned wood only to come to find out that it is neither dry enough nor seasoned enough for my liking), what's the best way to get a really hot fire going? At times I've been able to get the house thermostat to read 70, but lately I can't seem to break 65. Any and all help is appreciated!

 

[coaly]

Welcome to the forum;
You should use a mirror and flashlight to look up the outlet vent to make sure the damper fully opens and fully closes. Then you will know what position the damper is held in at each notch of the lever. Someone could have added a spring, made their own linkage or repaired it to make it work totally opposite. Normally just the weight of flapper closes it.

It doesn't take much excess moisture in wood to cause problems. The moisture takes energy to remove and carries BTU's along with it up the flue.
If it sizzles or you see liquid bubble at the ends it is too wet. Seasoning starts when it is split, and many split and deliver right away feeling since it lays around in the round, the ends look dry and cracked, but that nothing for the inside that counts. The more moisture in wood, the faster it dries, so it takes much longer to finish than when you start seasoning. Try stacking it crisscross fashion for lots of air flow. Bringing it in near the stove for about a week helps a lot too. You can only get it and season in advance so you know what you have.

Here's what I need to know to answer the low heat question;
First, is the Insert slid into fireplace as shown in manual, or is the flue connected directly to the top of insert ?
Is chimney flue masonry or lined with insulated liner and what internal size (diameter and shape) is the opening all the way up?
Chimney height?

Post #13 in thread below is a good explanation of how the chimney becomes the engine that runs the stove. Apply that to your installation and it will probably answer the question. Not sure what you have there.
https://www.hearth.com/talk/threads/jacksnipe.150735/#post-2034108

 

[Flynnworx]

Here's my newly installed smoke shelf

 

[Flynnworx]

20-1/2" x 14" x 3/8"