Heatilator removal, terra cotta liner and insert installation questions

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New Member
Oct 16, 2022
Greetings Hearth and huge thank you for the wealth of info and help shared here!

I have what appears to be an early version of Heatilator (house built in 1940s and guessing heatlilator is original?). Guessing it needs to be fully removed given the rust and deterioration.

Also bought a very nice used Quadrafire 4100 with 12'+ of 6" double wall insulation and a 5' section of 6" stainless flex ducting that we are (were) hoping to install - plenty for our chimney height.

I tried cutting a center section of the heatilator out (removed damper, etc.) in hopes it would allow for the 6" pipe to route past the heatilator without having to remove the whole thing, only to find that we have what is likely a 8x18 (o.d.) terra cotta liner past the top of the heatilator to the top of the chimney about 10' +/-.

So the (noob) questions are;

- Can the 6" round be run into / through the terra cotta (doesn't seem like it will fit, aside from not being safe?)
- Or, can we use the existing terra cotta as is (without a liner)?
- Better / best to remove the heatilator with as rusted / deteriorated as it is?
Photos attached - can provide more photos or info if needed.

Thank you!

IMG_3771.JPG IMG_3775.JPG IMG_3777.JPG IMG_3778.JPG IMG_3781.JPG IMG_3782.JPG


Chimney sweep
Staff member
Jan 14, 2014
central pa
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Staff member
Nov 18, 2005
South Puget Sound, WA
It looks like this will need an insulated, oval liner that transitions to round above the insert.


New Member
Oct 16, 2022
Huge thanks to you both @begreen & @bholler - beyond your lightening fast responses, really appreciate the expertise you share.

Will seek out the oval, insulated liner and transition pieces and report back. Thanks again!