When to close bypass gate for CAT?

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Emu456

New Member
Quick question about when to close the bypass on stove. I have a Federal Airtight that came with the house I bought last year. I used the stove all of last year with no problems at all. My question is from what I read online that I should wait till the temp of the Cat reaches 500 degrees before closing the bypass in order for the Cat to burn properly. However, the instruction booklet ( which I just found) says to light fire and once "the fire is going" to close the bypass and then states the CAT will begin to work as intended once it reaches 500 degrees. Which way is correct? Or are they both correct? Thank you.
 

fire_man

Minister of Fire
Feb 6, 2009
2,587
North Eastern MA
Those instructions seem odd to me since the whole concept of the Cat is it burns the smoke once it reaches the critical ignition temperature and not before. If it's not burning smoke then it clogs quicker.

It's not my place to disagree with the manufacturer's instructions but I agree there is a disconnect with conventional wisdom.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,524
Mt. Rainier Foothills, WA
Maybe by “the fire is going” they mean wait until flue gasses hit 500 degrees. I often engage the cat when either flue temps or cat temps exceed 500.
 

fire_man

Minister of Fire
Feb 6, 2009
2,587
North Eastern MA
Here is a quote from BKVP who is pretty darn qualified to answer this question:
(it was in this thread https://www.hearth.com/talk/threads/prolonging-catalyst-lifespan.170785/page-2#post-2292274)

screenshot_961.jpg
 

Emu456

New Member
Ok, makes sense. I have been waiting for the temp to reach 500 before engaging the CAT, but just noticed the difference in the instructions for the stove which I just found. Just double checking the correct way to start the CAT. Thanks everyone!