What actually happens when you engage the cat ..... ?

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Boozie

Feeling the Heat
Hearth Supporter
Dec 11, 2010
273
SW IN
When you push in the bypass damper I don't hear anything. I don't hear anything turn on, whirl, make any noise whatsoever. So what does the cat do up there? Does it turn, does it whirl ...... just what is it doing? I know it is eating up the smoke and making the air cleaner before it leaves the chimney, but how does it do it.

I know ..... another crazy question from a "guuuuurl". :lol: I just like to know how things work.
 
Ummm, you get kittens? :)


When the bypass is engaged the smoke path is changed from directly to the flue to passing through the catalyst. No moving parts.

Condar has some good info at: http://www.woodstovecombustors.com/How_They_Work.html. More links on the left for info on how to best operate, clean, etc.
 
So it's a filter?

and .... no, I don't need any kittens. They show up at my door unannounced as it is. :)
 
Not a filter, it's more of a reactor that combusts unburnt wood gas as it passes through it.
 
That was a very informative link. So, it's a "reaction" that's taking place ....... veeeeeery quietly. :)
 
Ahhhh hahah just as I suspected..girls ARE stupid, ugly and have germs!

The proof in the pudding is when you close the bypass wait a few minutes and look at the chimney. It's amazing how your stove will cook so long on one load of wood with zero smoke.
 
Franks said:
Ahhhh hahah just as I suspected..girls ARE stupid, ugly and have germs!

The proof in the pudding is when you close the bypass wait a few minutes and look at the chimney. It's amazing how your stove will cook so long on one load of wood with zero smoke.

I'm just ........ curious. ;-P

..... and for the record ...... I've never run out to check the chimney. :lol:
 
Boozie, try it sometime. 20-30 min. with the bypass open on a fresh load, go check. Then close the bypass, wait 5-10 min. for the cat. to get a little warmer, and check again. you'll notice reduced smoke. check it every 15 minutes until you're down to coals. You'll see the difference.
 
Here is a link to some good videos put out by Applied Ceramics who make the Firecat combustor. Very informative.

I didn't think I wanted a cat stove but there were so few EPA cert stoves coming up on the used market that I couldn't be that choosy. Now that I have lived with it for a few weeks, I don't know why I felt that way. I think I was put off by the idea of a $300 part that needed replaced as a matter of course but not really an issue every 6 years or so. Anyway, these are very informative.

(broken link removed to http://firecatcombustors.com/videos.htm)
 
Boozie said:
When you push in the bypass damper I don't hear anything. I don't hear anything turn on, whirl, make any noise whatsoever. So what does the cat do up there? Does it turn, does it whirl ...... just what is it doing? I know it is eating up the smoke and making the air cleaner before it leaves the chimney, but how does it do it.

I know ..... another crazy question from a "guuuuurl". :lol: I just like to know how things work.

Picture it this way. In the back of your stove there is a huge hole that the smoke goes out of and up the chimney. In the front there are a bunch of tiny holes for the smoke to go through.

Pull out the BP knob and it opens the big hole in the back and all that smoke goes up the chimney without getting burned. Push in the knob and it covers the big hole in the back and forces the smoke up through the little holes of the catalytic combustor. The reason to do this is that the smoke goes into the cat at about 500* and comes out at 1000 to 1500* and you get to feel all that heat instead of sending it up your chimney.

Hope this isn't too simple.
 
WoodpileOCD said:
Hope this isn't too simple.

I like simple. Thank you. :)
 
Any sufficiently advanced technology is indistinguishable from magic.
 
Barb, go to this website.

Woodstock

Then look on the right hand side of the page under Information and you'll Company Blog and then New Stove Blog.

Click on the New Stove blog and it will want to download a pdf file. Download it and read it as there is some great information about cats.
 
Boozie said:
That was a very informative link. So, it's a "reaction" that's taking place ....... veeeeeery quietly. :)

You expected an atomic bomb? %-P

As is pointed out in the Condar article:

A catalyst is a substance that lowers the activation energy required for a chemical reaction to take place, without being consumed by the reaction. Heat is required to activate the reaction.

Not mentioned is that oxygen is also required for the reaction. If you make too much smoke for the amount of available oxygen, no catalyst in the world will be able to burn up the smoke. The catalyst itself is not part of the reaction, only the wood smoke and oxygen end up in the products of reaction. Without enough oxygen, all you will get is warm smoke.
 
I can't tell you. National security is involved.
 
This interesting article was on a recent thread:


(broken link removed)


Below is a diagram of a working combustor:
 

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Battenkiller said:
This interesting article was on a recent thread:


(broken link removed)


Below is a diagram of a working combustor:

Don't think that is quite the reaction I am getting in the Vigilant. More like all stuff going in and all stuff going out.
 
Remkel said:
Battenkiller said:
This interesting article was on a recent thread:


(broken link removed)


Below is a diagram of a working combustor:

Don't think that is quite the reaction I am getting in the Vigilant. More like all stuff going in and all stuff going out.

Might be time for a new cat.
 
The Vigilant is a non-cat stove. If it is burning poorly, it may need a complete cleaning.
 
Not the best choice for full-bore burners like Remi and I anyway. See how poorly they do at a higher burn rate compared to a typical non-cat? The cat stove is more than ten times cleaner burning at low burn rates, but produces twice as much PM as a non-cat when running at maximum burn rates.

This table was part of a presentation given by Chris Neufeld, Vice President of Blaze King Industries, Inc. Nice of him to admit that a cat is not the final answer in all circumstances. What the table doesn't show, however, is how much more efficiently a cat stove is at burning off non-particulate matter. Methane, carbon monoxide, acetic acid, formaldehyde, VOCs, hydrogen gas, and a host of other substances produced inside the burn zone are not part of the EPA testing, but these are all fuel gases as they come out of the primary burn zone. These won't show up as "smoke" as they exit the chimney, either, so no matter what you see coming out, trust me, there is unburned fuel coming out clear as can be. The cats get most of this stuff to burn, thereby helping to boost the total combustion efficiency even higher than the EPA tests might predict.
 

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