Xtrordinair 36A busted catalytic combustor

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New Member
Dec 20, 2022
Just moved to a new house recently in TX. This is my first house with a wood fireplace insert (I believe it is a Xtrordinair 36A). We had the chimney swept to make sure we were starting fresh. Had a fire two nights ago and all went well. Had a fire last night and as I was reloading wood I couldn't get the combustor bypass rod to shut (push in). Not knowing what's going on I decided to leave it and let the fire burn out. Looking at it this morning I see what looks like a chunk of the combustor honey comb resting on a plate in the top back part of the fireplace. I know almost zero about any of this and there is single digit storm coming (that is bad in TX). Clearly I need to rebuild the whole catalytic combustor. The question is can I pull this a part, when it cools, remove the chunks, get the rod working again and still have a fire for the next few dangerously cold days? On top of it I have house guest staying with us for xmas. Seriously any help would be much appreciated. Thank you.
I opened this thing up and sure enough the long rectangular honey comb piece was busted in several chunks. One chunk fell down and was blocking the damper rod from going in. I puzzled the combustor pieces back together and put it back in place. I think if gentle, that will get us thru this cold spell and holiday. I still ask the question though. If I just pull the pieces out can I run without the combustor (or some of it anyway) for a few days? I know this isn't as efficient and may cause creosote build up, but is it dangerous? Or are there other consequences I should be worried about? Definitely not a long term solution, I understand.
I’m not familiar with your stove, but the manual for my catalyst stove (Buck 91) states that it is against federal regulations (EPA, I’m guessing) to operate it in a manner inconsistent with its instructions, or without the catalyst , or with a deactivated catalyst.

Here’s a real life story; our stove was already in the house we purchased, and for the first 2 seasons we ran it (assuming it had a catalyst since we had it inspected). Turns out it did not have its catalyst, nor its flame/heat shield, installed. AS FAR AS I KNOW we did not hurt the stove, and it still operates great today - we installed a catalyst, heat shield, and replaced all of the door/glass gaskets November 2020.

If it were me, and we’re in the path of this storm also; I would remove all of the catalyst pieces so they don’t fall in the fire or jam your slide again, order a new catalyst, and use the stove in the meantime. You may want to run it a bit hotter to keep your flue temps up to prevent creosote since you won’t have the cat cleaning your smoke. When we used ours without the catalyst we operated it as though it did have one (we didn’t know), even closing the damper/bypass at the indicated temps. We still had a secondary burn, and our chimney (liner) was clean after, but your mileage may vary.

Whether this will work with your stove is your call, hopefully others with more specific advice or experience will reply.
Be safe!
It’s fine to burn it for a short time without the cat., especially with a cold snap coming.
Firecat combusters says it’s a discontinued product unfortunately. It’s a 36A, not a 36 elite correct?
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Thanks everyone for the comments. Yes I believe my fireplace is a 36A (not elite). I looked and looked for the a serial number on it and never found one. So just some investigating online and looking thru discontinued stove manuals. The 36A seems spot on and the 36 elite is different. The 36A manual says the supplied Cat is a Corning, Inc. Model 3.125 X 14.25 X 3-16, cell density = 16 per square inch. So that Condar one does look correct in size. I probably should go take it back a part and measure before ordering. Hopefully they actually have them.

It is super interesting that I might be breaking the law by running this without a cat. It wouldn't change my mind in this situation, but just kind of funny. I wouldn't even have thought of that.

Well I am gonna run this thing over the holiday and see how it goes and then see if I can find a cat, probably start by calling this woodstove combustors. Spendy little buggars.

Thanks for the help and/or reassurance, stay warm.
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It is super interesting that I might be breaking the law by running this without a cat. It wouldn't change my mind in this situation, but just kind of funny. I wouldn't even have thought of that.
I imagine it’s a liability thing, like CYA (cover your a**). And an EPA compliance thing. I don’t believe the stove is more or less safe with the catalyst, I believe it operates better with the catalyst - fewer emissions, less wood, longer burns, etc. Our home insurance may feel otherwise, but as mentioned, I’d still run it and get the new catalyst ordered. Yeah, they’re not cheap. Be safe, stay warm, too.