Chimney Thimble add

Chimney Thimble add

PostBy: andrew241 On: Thu Sep 18, 2008 11:41 am

I currently have a wood/coal furnace and love it. This year I am thinking about tryinhg out coal for the first time but there is an issue with the location of the thimble in the masonry chimney. There is only one location I can place the unit and I need 3 elbow just to connect it to the chimney. I want the connection so I can cut out all those elbows. Basically can I add a thimble and how do I do it? There are 3 total on it already, 8", 6", and 4" and they are all on the one side.
andrew241
 

Re: Chimney Thimble add

PostBy: LsFarm On: Thu Sep 18, 2008 12:32 pm

If you have adequate draw with the current flue pipe setup, even though it has three elbows, I'd live with it.. every time you cut another hole for a thimble in a chimney, you weaken it, risk cracking the masonry in ways you did not intend.. right now, with all three openings on one side, you have two sides and a back of the chimney 'stack' that is untouched and is supporting the weight of the masonry above.. if you cut into one of the sides, you have posibly compromised the strength of the chimney..

When burning coal, you don't have the issues of creostote, which probably was a problem with the three elbows in the flue pipe.. With coal, you just need a clean pipe with an uphill run from the burning appliance to the chimney..

I'd get the chimney cleaned, so it will draw as good as it can, put in new or clean flue pipe and elbows, and use it that way..

Now,, you mention three thimbles in the chimney right now,, are the other two capped or in use with other appliances?? If in use, these items are stealling draft from your wood/coal appliance... and they offer a way for fresh air to get to a possible chimney fire, making a chimney fire uncontrolable.. You don't have any fear of a chimney fire with coal, but you do need a steady reliable draft to keep coal burning steady..

Hope this helps.. Greg L
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Chimney Thimble add

PostBy: andrew241 On: Thu Sep 18, 2008 2:07 pm

Thanks, that was my fear with moving the thimble to the other side. With the elbows I get build ups a from the wood and clean them out 1 or 2 times a season. I want to avoid that this year if I can but it sounds like with coal I shoudln't have those issues.
andrew241
 


Re: Chimney Thimble add

PostBy: LsFarm On: Thu Sep 18, 2008 3:47 pm

You will have fly ash in the flue pipes, but this is much easier to remove than creosote,, just a vacuum will clean out fly ash.

Greg L
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland