Hello. I have a Heatilator MF36 fireplace with a TB48 metal chimney surround. The old top seems to let in some rain water, not a very good design, or pleasant to look at. I had to replace the interior refractory panels and hearth due to age and water. I was wanting a stainless steel chase cap installed with a new air cooled cap, but the contractor says they need to extend the current liner and flue above the chase cap for proper air cooling. Makes perfect sense for how the system works, but for code they need the factory piping, with 8" inner and 13" outer diameter liner. According to Heatilator these parts, Part AC512 (12") are no longer made. The old cap had the liner terminate below the surround, and a single pipe inserted into that which led to the termination cap. Based on this, the extension pipe was letting some heat up the seam, as its not perfectly concentric within the 8" chimney pipe. Bad design, considering this is exposed to the attic below the cap.
Is there any way to identify what these fitting types are, get them from a third party or have them custom made? Or would the entire chimney flue system need replacing. Its not a very efficient fireplace circa 1983, and I will eventually replace with something more efficient in the next 5-10 years or so. But i would like to enjoy the fireplace now safely. Considering how bad the single wall pipe extension was, i'd say extending the 13" liner would be beneficial and protect the house better than how it was originally installed. This is what I envision it would look like completed, minus the siding of course. Or am I stuck using the old cap, and maybe just cleaning it up some? Is that current extension a fire risk?
Is there any way to identify what these fitting types are, get them from a third party or have them custom made? Or would the entire chimney flue system need replacing. Its not a very efficient fireplace circa 1983, and I will eventually replace with something more efficient in the next 5-10 years or so. But i would like to enjoy the fireplace now safely. Considering how bad the single wall pipe extension was, i'd say extending the 13" liner would be beneficial and protect the house better than how it was originally installed. This is what I envision it would look like completed, minus the siding of course. Or am I stuck using the old cap, and maybe just cleaning it up some? Is that current extension a fire risk?
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