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Running cat in bypass, safe?

Discussion in 'Modern EPA Stoves and Fireplaces' started by cezar, Nov 12, 2022.

  1. cezar

    cezar

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    My stove is new and I think a little overactive and it likes to go into the "TOO HOT" zone a little easily. But that said, it is possible to run a cat too hot in general use occasionally, right?

    So doesn't it make sense to bypass the cat when too hot, just as you would when too cold? To preserve it?

    Reading through the manual for my stove (Clydesdale), it seems to strongly imply (but cannot state due to EPA regs) that the bypass should "remain closed when in the active range". So if it's above the active range logic would dictate the best move for cat longevity would be to open the bypass.

    I feel like I read somewhere that running a hot stove in bypass mode can damage the bypass mechanism, but that explanation doesn't really hold water for me. Is there a reason to keep a cat engaged when it's in "TOO HOT"?
     
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  2. Backwoods Savage

    Backwoods Savage Moderator

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    What is the stovetop temperature when this happens? I would think if cat too high then stovetop would also be too high. Hint: one time I was gone and when I returned home my wife was standing at the stove worried it was running too hot. Stovetop was around 700 degrees. She said she had been babying it for about 20 minutes. I looked and she had the draft closed. She about flipped when I gave it more air! Yet the stovetop temperature immediately started dropping. It settled around 650 degrees if I remember right. She learned a good lesson that day.

    I have never been concerned with this and it has never been a problem. As for damaging the bypass system, I don't see how that would happen.
     
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  3. moresnow

    moresnow

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    A new Cat will often run exceptionally hot. Not unusual to see the Cat probe gauge wrapped waaay beyond the normal scale on a new Cat. After a number of cycles, the Cat will become less reactive. If the Cat probe is active I leave the Cat engaged.
     
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  4. cezar

    cezar

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    Yeah I know, but it still makes sense to me not to let it run away if it is as simple as pulling a control rod out for a bit. I mean, at some point I'll get new cats so should I subject them to high temps just because?


    I am really starting to suspect this is a sensible idea but none of the stove manufacturers can talk about it because it implies elevated emissions while bypassed.

    The question is basically: does bypassing a new and hot cat prolong its life versus doing nothing?
     
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  5. Highbeam

    Highbeam

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    I think this is stove specific. I know for certain that a BK stove will be damaged if you run it hot with the bypass open. Not cool.

    Maybe other brands are more forgiving of this.

    I don’t believe any brand will advise you to bypass the cat once the stove is beyond minimum catalyst engagement temperature. That causes pollution.