Puff the magic dragon (stove)

What does the 8" flue thimble connect into? Is there a liner in the chimney and if yes, what size? How tall is it?

Oak takes a long time to season well. A modern stove is going to be more particular about the dryness of the wood burned and the amount of draft.

Modern stoves want dry wood and decent draft to perform correctly. If the chimney height is at the minimum draft will be decreased by the two 90º turns in the smoke path. An increase in the flue size will further dilute draft.

Is there a clay liner currently in the chimney? What are the interior dimensions of the chimney?

It's not the stove that is the problem, you are not getting the flue outside hot enough. When you get the chimney flue hot and drafting properly, opening doors or leaks will rush into stove and up chimney - making it burn harder, you won't have a smell of smoke inside no matter what stove is there. Make sure there is no clean out door leaking cold air into chimney flue. The height of your chimney could be the factor since we don't know the area inside the flue you're heating to create the proper draft.

Leaks in the front doors will make it burn harder when you have the correct draft from the proper flue temperature.
Your statement " I am done with this smoker! The front doors are not sealed and if I sealed them it would not be able to get oxygen" is an indication you probably don't know the basics of what makes the stove work.
I'll clip and paste the basics from a thread explaining this to a similar poster from the Fisher Forum.
You want to measure the inside dimensions of flue and let us know how high in feet the chimney is. This will give us an idea of how strong your "engine that makes the stove work" is.

Here's the basics;
The chimney is the engine that drives the stove. Hot rising gasses are hotter inside the flue than out. The more temperature differential, the faster they rise. This is draft. The first purpose is very clear, to expel smoke and unwanted byproducts of combustion. The second and most important is why the insulated flue is best. The rising gasses create a low pressure area in connector pipe and stove. (a slight vacuum) This allows atmospheric air pressure to push into the stove feeding the fire oxygen. So the hotter the flue inside and the colder outside, (outdoors at chimney top) the stronger the push into the stove. The smaller 6 inch flue is almost half the size of the 8. Those two inches in diameter almost doubles the square inch cross sectional diameter. So the larger flue takes almost twice as much heat (waste) to get the same results of air pushing into the intake. The insulated flue stays hotter inside much easier making the stove more efficient using less wood. The other advantage with an insulated flue staying hotter is less creosote. 250* is the temperature you must stay above all the way to the top. At 250* water vapor from combustion condenses on the flue walls causing smoke particles to stick. This is creosote. So the insulation requires less heat to be left up to keep clean. That's why older stoves can then be baffled inside to put the heat to stove top instead of needing it up the chimney.

Any opening into flue other than the stove through intakes also allows atmospheric pressure to leak in. This cooler air cools the flue gasses which slows draft since there is less temperature differential decreasing the amount of air going into stove.

So you can see why a more efficient newer stove requires a 6 inch chimney. First , they don't waste enough heat out of a smaller 6 inch outlet to heat a larger area of flue inside. The same goes for 6 inch older stoves connected to larger chimneys.

ramzzey13 said:

I would rather get a newer model that I know for sure did not have a smoking issue. One that is EPA checked

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If you install it on your current chimney there is a good possibility of it still smoking.


I would recommend getting the chimney inspected before going any farther. Yes you could line it but if that metal chimney is in bad shape do you really want to spend the money to line a chimney that is gong to start falling apart in a few years? And the dimensions you are giving don't sound like normal chimney pipe that is used for wood stoves another reason to have it inspected. You need to know what you have before figuring out how to change it.

ramzzey13 said:

If I inserted say a 6" liner inside my 8" the whole way down from cap to stove would the 8" pipe essentially be a form of insulation (not great but better than direct exposure to elements) for my 6"? And then run that down all the way to the stove of my choice?

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I would insulate the liner also. It doesn't cost that much more and it will improve performance.

No mention of a damper either. (possibly top mounted?) Improper use of one is going to cause smoke and smell.
As Rich L mentioned above, negative pressure from mechanical fans or other appliances reduces the air pressure at the intake of your Fireplace reducing the push of air into it headed up chimney. It all goes back to the basics of the chimney making it work.

I was confused by the title calling it a "dragon" which is a term for an air tight stove burning with too little air, and using stove in the title. To little air should not be your problem, and too much air should burn fast with little to no smoke.
The part that confirmed you had an air tight stove was mentioning adding door gasket material to seal doors. That is for an air tight stove to assure all air is controlled through air intake only. It appears to have screen doors, so the gasket is not necessary. We're on the same page now

With screen during open door burning, (older double door stoves and fireplaces) the only air control you have is with the flue or pipe damper on the exhaust. Normal operation is getting flue hot (above 250* to top) and slowly close damper until smoke starts to roll in at top. Open slightly, and that is your setting for the flue temp and atmospheric pressure at the time. That captures the most heat while venting combustion products. Learning the damper will get the most heat out of it.

Not only does a fire simply require air, appliances are normally designed to provide 40% more oxygen than required for a cleaner burn.
The reason you need air is to mix with the flammable gasses expelled from the fuel as it heats causing the visible flame.
Turbulence creates a better mix. So in your case, velocity and the way you load with air space and making the flame change direction gives a cleaner burn. (Velocity is controlled with damper) You can do a lot wrong to cause smoke. Not enough air produces charcoal. Here's the reason more air than necessary is required in a controlled fire; Air can't mix with the flammable gas coming out of a log - it mixes outside the log. Only excess oxygen molecules that wander onto the surface cause ignition of carbon monoxide. (Carbon Monoxide and Hydrogen are created by water vapor being expelled from log and contacting the charcoal layer) That is the blue flame when burning properly near the wood. Hydrogen burns clear.

20 feet at 200* f (flue gas minus outside temp) puts your chimney right in the middle of the chart at -.08 inches of water column. Some higher performance appliances will give WC required, or the manufacturer can give that to you. That's normally done with coal appliances since draft becomes much more critical and is set to exact requirement with a barometric damper.
Figure a little less since it looks square in picture probably 7 1/2 square ? equaling 56.25 square inches where a round 8 inch is 50.24 square inches.

To really learn about using wood as energy, I recommend finding "The Woodburners Encyclopedia" by Jay Shelton that comes up on eBay. It's the best I've found covering all aspects of wood burning, appliances and venting. No matter what stove you end up with, you will use the information in that book.

I assume that is double wall Class A Chimney ?? It could be fireplace chimney which is not rated high enough for a controlled combustion wood stove.
The bottom clean out is pictured open with no cap. It is sealed with something when in operation, correct?

Measuring won't tell you if it is double wall connector pipe, or 2100* rated Class A Chimney. You need to find a label or have someone who knows what it is tell you.
As vasten describes above, there are two chimney types. "Pack" which is normally stainless steel inside with dense insulation between inner and outer wall. They are quite heavy and lock together with a twist. You can see and feel them at Lowe's under the Supervent brand name.
The other type is triple wall with a thin wrap of insulation between inner stainless liner and second pipe, and finally an outer pipe with air space between second and outer. They also twist lock together. You can see and feel them at Home Depot sold under Dura-Vent brand.
They are both rated the same and safe.
Prefab chimney for fireplace only is not rated as high since a fireplace flue stays much hotter and burns much cleaner since you don't have precise air control. In the case of creosote formed by an air tight stove, they can burn through or melt and may not withstand a chimney fire.
If you have single wall connector pipe, it is not a chimney at all and outside air cools the inner wall rapidly. It will not stay hot enough inside and will not draft properly to evacuate smoke or cause the needed pressure differential to make a stove work.

There are several moisture meter threads in the Gear forum here.
https://www.hearth.com/talk/forums/the-gear.7/