Those who have run their stove with clay flue, then stainless liner. Chime in please

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

SIERRADMAX

Feeling the Heat
Jan 13, 2011
300
RI
I know there are many factors in considering draft, stove performance, chimney height, etc.

I recently posted a topic about connecting a Harman Oakwood to an 8x12 clay flue. Someone posted an informational topic that the flue is to large for the stoves optimal performance. Later, I measured the actual flue size at the cleanout and it's a 7x11 OD, 6x10 ID. Thus 60 squre inches internaly, a little more than double the square inch of the 6" stove pipe.

My question is, has anyone ran their stove (similar) for a season or two, then switched to a liner and noticed better perfromance/less creosote buildup?
 
I had the same sized chimney as you and once I lined it with a 5.5" liner the difference was like night and day, longer burns, more control and less creosote. If it's an outside walled chimney you definitely want to reline, it's hard to keep those large tiles from cooling down mid Winter and those downdraft stoves like yours can be very draft sensitive.
 
Yes - Night and day difference. More than a gallon of creosote from Spring cleaning before vs. about a cup of fly ash after.

Lighting ease with liner: darn near priceless.

ATB,
Mike
 
I went from a 7 1/4 by 7 1/4 in clay lined chimney to a 6 inch liner and it was night and day. Stove ran OK before. But the FIRST fire I had w/ the liner I realized what I was missing.

IE. Stove wouldn't run that great until it was 40 degrees or less out. Now I can ran that bad boy anyway I like right up to 60 degrees.

ETA: Also couldn't believe the difference in how clean the chimney was. Before the SS liner I never had much creosote, but it looked like coffee grounds to "fruity pebbles" black creosote. Now I get nothing but grey sooty dust which is much safter stuff to have in the flue.

pen
 
My sweep told me that most of the smoke travels upward in a spiral path, with the hottest part in the center of the flue. That leaves the corners of the rectangular flue cooler, and more likely to accumulate creosote. Once it begins to form, new creosote sticks to old creosote and it accumulates more rapidly, kinda like what happens to some folks with their cap screens.

You can get a good draw up a flue that is too big, but you need to raise the flue temp up to the point where the chimney is drawing well. Since there is more space inside the bigger flue, that means more total heat is going up the flue for the same benefit in draft strength. Very wasteful. Even if the chimney goes directly through the living space and you can reclaim some of the heat, all of the excess hot gases going outside are carrying sensible heat away from your home.
 
Yep BK eddy currents, read that 30 years ago when I put the chimney in and the only thing I could find was the round 7/1/4 but it worked well, I do have a cooler flue now so I hope I am losing less heat up the flue.
 
I know this is kinda off topic, But which works better 8" Chimney are a 6" chimney for a better draft. Since the tile 7 1/4" x 7 1/4" chimneys are cooler then a chimney flue pipe.
 
AppalachianStan said:
I know this is kinda off topic, But which works better 8" Chimney are a 6" chimney for a better draft. Since the tile 7 1/4" x 7 1/4" chimneys are cooler then a chimney flue pipe.

It's best to match the size of the flue w/ the size of the stove's flue collar. 6in stove = 6 in chimney. 8 in stove outlet = 8 inch chimney

pen
 
pen said:
AppalachianStan said:
I know this is kinda off topic, But which works better 8" Chimney are a 6" chimney for a better draft. Since the tile 7 1/4" x 7 1/4" chimneys are cooler then a chimney flue pipe.

It's best to match the size of the flue w/ the size of the stove's flue collar. 6in stove = 6 in chimney. 8 in stove outlet = 8 inch chimney

pen

It sounds like a 6" stove and a 6" chimney will run better than an 8" stove and a 8" chimney. Less mass to heat up in the chimney?
 
I have a Regency insert that I ran two years on a 12x12 clay liner on a outside chimney. It was ok I didn't think I was missing anything. I changed to six inch stainless insulated liner because I didn't want to pull the insert out everytime I cleaned the chimney. I got an insulated liner because it was recommended on this forum. I've had the liner two years now and I noticed more draft. I can now run the insert with the primary air closed off and my window stays clean. Definetly a very noticable improvement.
 
AppalachianStan said:
pen said:
AppalachianStan said:
I know this is kinda off topic, But which works better 8" Chimney are a 6" chimney for a better draft. Since the tile 7 1/4" x 7 1/4" chimneys are cooler then a chimney flue pipe.

It's best to match the size of the flue w/ the size of the stove's flue collar. 6in stove = 6 in chimney. 8 in stove outlet = 8 inch chimney

pen

It sounds like a 6" stove and a 6" chimney will run better than an 8" stove and a 8" chimney. Less mass to heat up in the chimney?

Well, you're burning a lot more wood in a stove that needs that much exhaust capacity. So, yes, you will send more heat up the flue, but you will also send a lot more heat into the living space. Probably the same ratio in either system, anyway, so you lose a little more up the flue but you gain a lot more back in usable heat.
 
I have a similiar clay flue, and have it lined to the cap. I was told by a friend who has been burning for 30+ years, that this set up is the safest against chinmey fires, and if one did occur, it is not likely to harm the house....thoughts...no disclaimer needed.....I do load up the insert and leave for 5 hours, don't care about the house, more worried about the dog.
 
Beer Belly said:
I have a similiar clay flue, and have it lined to the cap. I was told by a friend who has been burning for 30+ years, that this set up is the safest against chinmey fires, and if one did occur, it is not likely to harm the house....thoughts...no disclaimer needed.....I do load up the insert and leave for 5 hours, don't care about the house, more worried about the dog.
I think that was true 30 years ago but I believe the ratings on the insulated steel chimney meet or excede the clay liners now.
 
oldspark said:
Beer Belly said:
I have a similiar clay flue, and have it lined to the cap. I was told by a friend who has been burning for 30+ years, that this set up is the safest against chinmey fires, and if one did occur, it is not likely to harm the house....thoughts...no disclaimer needed.....I do load up the insert and leave for 5 hours, don't care about the house, more worried about the dog.
I think that was true 30 years ago but I believe the ratings on the insulated steel chimney meet or excede the clay liners now.
So then, having the steel lining, running inside the original clay flue, is as my friend claims ??
 
I misread your post and thought you were comparing steel to a clay liner, I do think your set up would be very safe.
 
Battenkiller said:
My sweep told me that most of the smoke travels upward in a spiral path, with the hottest part in the center of the flue.

Ah yes The Coriolis Effect. It used to keep unscrewing my chimney cap until I bought one made for South of the Equator. :coolsmirk:
 
I have the same chimney as the original poster (6" x 10" ID). Couple additional questions....

- If going with a liner, is it better to go rigid or flexible (if it's a straight shot down)?
- Is a 6" liner (flex or rigid) going to fit down our 6" wide chimney? Or would we have to go with a 5 1/2"?
- If it does fit, probably won't be able to wrap insulation around it.... Use the pourable insulation instead? Would it really be worth it if a bunch of the liner is jammed against the existing clay liner anyways?

Thanks!
 
The nominal outside diameter of a six inch I.D flex liner is 6.25". Ain't gonna fit. 5.5" inch is your best bet. Rigid won't fit either.
 
Duraliner makes an insulated oval liner for this application.
 
Beer Belly said:
I have a similiar clay flue, and have it lined to the cap. I was told by a friend who has been burning for 30+ years, that this set up is the safest against chinmey fires, and if one did occur, it is not likely to harm the house....thoughts...no disclaimer needed.....I do load up the insert and leave for 5 hours, don't care about the house, more worried about the dog.
I want to add chimney fires are never a good thing and your burning practices are the best line of defense against them.
 
I had the same sized chimney as you and once I lined it with a 5.5" liner the difference was like night and day, longer burns, more control and less creosote. If it's an outside walled chimney you definitely want to reline, it's hard to keep those large tiles from cooling down mid Winter and those downdraft stoves like yours can be very draft sensitive.
Did u line your chimney with 5.5" for a keystone stove!
 
Todd had a poured in place six inch liner installed for the Keystone.

Closing now.
 
Status
Not open for further replies.