Reusing an old masonry chimney-liner?

  • 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.

Badfish740

Minister of Fire
Oct 3, 2007
1,539
I'm posting on behalf of a friend who isn't very internet saavy, so this is all second hand. He is in the process of finishing the basement of his cape cod, which was built with a central masonry (brick) chimney that runs up the center of the house, exiting near the peak of the roof. The chimney had served a gas furnace for probably the last 25 years or so. A high efficiency gas furnace was installed about two years ago (just before he moved in) and is vented out the side of the house via PVC pipe, so now the chimney is unused. He would now like to use it to vent a wood stove that would heat the finished basement, and hopefully provide some heat for the first floor as well. He was asking me if I thought he needed a liner, but I really have no experience in that regard. My masonry chimney serves my oil burner and my wood furnace is vented via it's own Class A stainless steel chimney.

He is pretty sure the flue is clay lined (there is clay sticking out of the top-I'm not sure if that's a good or bad thing in terms of wood burning? In any event, I can help him with clearances, combustible/non-combustible surfaces, stove pipe, thimbles, etc...but if someone could help me with what to look for on his chimney to determine what the best course of action is I'd appreciate it.
 
The clay liner could be fine if it is not too large but should be carefully inspected. If it is in good shape then he may be ok to burn wood in it as long as the cross-sectional area is not above the stove requirements.
 
The clay liner could be fine if it is not too large but should be carefully inspected. If it is in good shape then he may be ok to burn wood in it as long as the cross-sectional area is not above the stove requirements.

What should it be inspected for? Cracks, etc...that would allow creosote buildup? Any other issues to watch out for? The cross sectional area was something I didn't think of... I have no idea how large it is, but even my Englander furnace only takes a 6" flue, so if it's larger than that he may have problems.
 
Cracks, mortar missing between joints mostly. Burning gas it should be pretty clean. If it is 8x8 tile that will have an ID closer to 7 x 7" which is ok for a 6" flue stove.
 
Status
Not open for further replies.