Woodstove connected to prefab flu

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Srbigbrown

New Member
Oct 14, 2015
1
Georgia
I have a black Bart wood stove insert. I would like to make it a freestanding stove. My existing fireplace is a prefab fireplace. What I was thinking of doing is taking the stove and running the flu for the stove up to 45° angle into the my existing flu. Can I do something like that? I know that it can't fit in my existing area of the insert. Because of the heat that radiates. I've been told by many chimney guys that I can't use it at all even just running the flu of the smoker mainly into the flu. My uncle has done a couple of new stoves out there and ran his into the flu is existing prefab fireplace it has never had a problem. Let me know what you guys think I can give you more details. It's a tempo insert that I have existing. The stove is like new that I got from somebody and I really want to make it work. I don't see what's wrongwith smoke going into the prefab flu. I would think most of the heat is on the actual stove itself. Any information on this would be greatly appreciated
 
Not sure if I got all that but here are some answers that probably apply to your situation:

1) A woodstove flue needs to be rated for 2100 F (HT); most prefab pipe is only rated up to 1700 F and can therefore not be used with a stove. When a stove has a 6" flue outlet you could drop a liner (HT-rated) down the 8" prefab chimney and connect it to the stove to make it safe and code-compliant. Your uncle may simply be lucky that he had not a chimney fire yet which could easily set his chase on flames due to the high temps it generates.

2) Using an insert as a freestanding stove is usually not a good idea. It becomes an unlisted heating appliance then and needs 36" clearance on all sides. That article may help: https://www.hearth.com/econtent/index.php/articles/stove_wall_clear
Plus, you need to follow NFPA 211 for your hearth protection. Your home insurance may also have an issue with that installation.

3) Those old-style "smoke dragons" actually don't keep most of the heat in the stove. Their efficiency is often ~40% with 60% of the heat going up the chimney. A modern, EPA-approved stove/insert will give you 70% to 80% efficiency. For both types, make sure to burn dry wood with an internal moisture content of less than 20%. That requires stacking the split wood in a sunny and windy spot for 1 to 2 years depending on the species.
 
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Just to add, most of those black barts have a rectangle exhaust, do you have the boot to adapt it to 8" round? Of that era and style they could be insert or freestanding, but still would not do what you are looking at doing as it is unsafe. Do it right and rip out the ZC fireplace and install new class a chimney and install a proper newer freestanding stove.

Of course the real question is, how much heat do you really need in GA?
 
Bad plan on many accounts including that the current installation is likely illegal especially if it's a slammer install, using an insert as a freestander voids UL testing, the ZC fireplace most likely has a 1700::F chimney and the wood stove is supposed to have a 2100::F chimney.
 
using an insert as a freestander voids UL testing

If that is the case then why is Buck saying it is acceptable for their old non-epa inserts to be converted which is what the OP has.

I have an older Buck Stove and I would like to convert it to a freestanding stove. Is this possible?
Yes, it is possible. You will need a stack and a pedestal to do so. First, you must determine which model you have. To do so, measure the rectangular opening on the top of the unit. If the opening is 13 ¾” x 3 ¼,” you have either a Model 26000 Old Buck (Little) or a Model 27000 Old Buck (Regular). Order part # FA 260421 for the stack and part # FA P4171B for the pedestal. If the opening measures 16” x 3 ¾,” then you have Model 28000 Old Buck (Big). Order part # FA 280421 for the stack and part # FA P4171B for the pedestal.

(broken link removed to http://www.buckstove.com/FAQ.html)
 
Thanks Mellow, if that can be done and with the mfg blessing + proper pedestal then it you are correct.
 
I don't see what's wrong with smoke going into the prefab flu. I would think most of the heat is on the actual stove itself. Any information on this would be greatly appreciated

A fireplace looses a lot of heat up the flue. This keeps the flue cleaner by reducing creosote to safe levels. The Insert or stove turns that wasted heat into radiated heat into the room. The lower stack temp makes it a more efficient heater. The air is more controlled and can be turned down or smoldered to rapidly form creosote. Below the condensing point of 250* (all the way up) smoke particles stick to the flue walls forming creosote. Creosote burns extremely hot when ignited, hence the requirement for a higher heat rated chimney.
Your uncle's installations may work fine until a chimney fire melts the lower rated chimney flue.
 
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