Hi500 Catalytic Combustor overfiring

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New Member
Jan 13, 2024
New England
Hello folks.
I'm into my third winter with this stove and just had to replace the Cat at the beginning of the 23/24 season. I was of the understanding that when the cat is engaged and the air control is all the way down, that there would be almost no visible flames and the wood would be "baking" instead of burning. My stove however looks like a blower is attached to the air inlet and will have large visible flames even when the air is all the way down and the cat is engaged. When I engage the combustor at 500 degrees, the stove will jump in temp to about 1200 degrees at the Cat probe. I can then see the combustor honeycomb glowing red like the manual says. Is this normal?

It seems to me that the stove, when up to operating temp, is pulling in a massive amount of air and burning too hot even with the air control all the way down. I've tried working with the dealer who sold it to me and installed it but they're not giving me much help.

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