My FPX large Hybrid is ready for a new cat- stainless?

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clydesdale

Member
Mar 8, 2016
180
New York
I have been running my degraded cat since the beginning of the season and it looks like I have taken it as far as I can. It is quite cracked and degraded. A have a new one that I can put in. But, it got me to thinking about the stainless steel cats. Are they more resilient? I vacuum my cat out periodically and that does help with flow. Using the brush that came with it seems to be a waste of time.
 
If you have problems with your ceramic cat suffering thermal shock, steel can help. First question is why your old cat broke up. Was it defective, did you shock it (usually by exposing to to cold air when it's hot, such as opening the door with the cat enagged), or does your stove have a poor design that allows direct flame impingement?

If the answer is poor design (and I can't answer that, not familiar with the stove), then absolutely go steel. You may still suffer substrate flattening but you won't suffer thermal shock.

If the answer is operational issues, you could either fix those or go steel to avoid doing so (for example maybe your spouse isn't interested in learning the stove and any ceramic cat is doomed).

If the answer is defective cat, go for a warranty replacement and try again.

Also, your stove manufacturer is not allowed to suggest a steel cat for you if they only tested the stove with ceramic, but cat manufacturers and sales sites will be happy to do so.
 
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I prefer the steel cats myself, like Jetsam said you can get substrate flattening but it won't crumble and fall apart like ceramic, Im not familiar with your stove though so cant say which is best for you.
 
Thank you for your guidance. I ordered a cat from mid west hearths on Amazon. Have any of you guys heard of that company? I went with the steel one. Thanks again.
 
I have a steel cat in my Intrepid. That's what it came with. It works well but in the intermediate range , say around 700 I'm not sure it would do any better. They don't make a ceramic cat for the Intrepid so I cannot compare unfortunately. The steel cat is supposed to light off earlier though. Around 450. So that's an advantage.
 
Do the steel cats not get as hot? That would not make me happy. Amazon has free returns on this item. It will be in tomorrow and I do not plan to put it in right away. I vacuumed my cat yesterday and it is heating fairly well again, but its days are numbered.
 
Steel cats get just as hot. Their lower thermal mass and higher thermal conductivity means that they light off sooner and drop out sooner. Some steel cats are more prone to plugging.

Having used both, I mildly favor steel, but they both worked well for me.

If your stove allows direct flame impingement onto the cat, I would wonder whose idea it was to put ceramic in there in the first place. (Probably nobody in engineering....)
 
I am hoping this cat will not be more prone to plugging. From what I understand, steel cats are supposed to handle the ash better and flow better. We shall see.
 
I am hoping this cat will not be more prone to plugging. From what I understand, steel cats are supposed to handle the ash better and flow better. We shall see.

This is false. The holes are much much smaller on a steel cat. More restrictive and easier to clog. The only benefits of steel are less likely to physically fall apart if that is a problem you have, and a slightly lower light off temperature for a slight reduction in emissions.

For the restrictiveness, think of it as a finer filter. Your BBQ grate is like ceramic and your window screen is like a steel cat. Extreme example but you get the point.

They cost more and since my cats don't physically break I don't see a reason to spend more on a steel cat to fix that problem.
 
I am hoping this cat will not be more prone to plugging. From what I understand, steel cats are supposed to handle the ash better and flow better. We shall see.
Yeah, when you said you vac the cat "periodically," I was gonna ask how often that was. How hard is it to get the cat out?
This is false. The holes are much much smaller on a steel cat. More restrictive and easier to clog.
That's been my experience..steel clogs a little faster.
What about that claim I've read, that the knife-like edges of the steel "slice the ash smaller so it doesn't clog."...that sounds like a load of baloney to me. I mean, the air is creeping through the cat when you have the air cut, and even if it was moving through faster, it doesn't seem to me that there would be any "slicing" going on. ;hm
 
What about that claim I've read, that the knife-like edges of the steel "slice the ash smaller so it doesn't clog."...that sounds like a load of baloney to me. I mean, the air is creeping through the cat when you have the air cut, and even if it was moving through faster, it doesn't seem to me that there would be any "slicing" going on.

Slicing ash seems like a load of baloney to me too. They plug with ash that is smaller than the holes anyway and the clog is not on the face of the combustor but within. Looks like a honeycomb full of honey and wax when they clog!

I've used both steel and ceramic cats in the same stove and both worked great for me. Nothing about steel justified the significant increase in cost.
 
Nothing about steel justified the significant increase in cost.
May just be that the steelies cost more to make for whatever reason..
 
To vacuum the CAT, I have a vehicle detail adapter that is for getting into small spaces in cars, like the a/c vents grilles. I attach that to the end of my ash vac and then lie on my back and vacuum the CAT from the front. I do this one time per week or two. The issue is that it has to be done installed. If I want to remove it and vacuum from both side, I have to remove it and that adds considerably more time and the stove has to be ice cold.
Before I bought the steel one, I spoke with Condar and they were emphatic that the steel one requires less cleaning and will flow better. They do not make one for my stove, but they referred me to the one that I purchased on Amazon. The rep was pleasant and helpful. Hopefully, she will be correct regarding the flow and maintenance. The center of the CAT definitely gets some flame exposure at times, so I am hoping that this will help. I think this CAT died extra early because I had it replaced under warranty and the CAT had moved forward in the tray and was getting pounded by the flames until I realized it. Once, I started pulling them in and out, I realized that the CAT should be pushed in deeper and less in contact with the flames. But, even in the proper position, where it is now, it can still get flame contact.
So, hopefully, steel will hold up better to that.
 
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To vacuum the CAT, I have a vehicle detail adapter that is for getting into small spaces in cars, like the a/c vents grilles. I attach that to the end of my ash vac and then lie on my back and vacuum the CAT from the front. I do this one time per week or two. The issue is that it has to be done installed. If I want to remove it and vacuum from both side, I have to remove it and that adds considerably more time and the stove has to be ice cold.
Before I bought the steel one, I spoke with Condar and they were emphatic that the steel one requires less cleaning and will flow better. They do not make one for my stove, but they referred me to the one that I purchased on Amazon. The rep was pleasant and helpful. Hopefully, she will be correct regarding the flow and maintenance. The center of the CAT definitely gets some flame exposure at times, so I am hoping that this will help. I think this CAT died extra early because I had it replaced under warranty and the CAT had moved forward in the tray and was getting pounded by the flames until I realized it. Once, I started pulling them in and out, I realized that the CAT should be pushed in deeper and less in contact with the flames. But, even in the proper position, where it is now, it can still get flame contact.
So, hopefully, steel will hold up better to that.
Hey , have the same stove, i'm on my second OEM cat this year. Before installing second one I made flame protector from perforated steel and put in front of catalizator. i'll see if it will help.
Can you provide link for the cat you got from amazon. thank you.
 
Hey , have the same stove, i'm on my second OEM cat this year. Before installing second one I made flame protector from perforated steel and put in front of catalizator. i'll see if it will help.
Another thing you can do..after burning in the load, cut the air and let the flames die back for a couple minutes before closing the bypass. It may be obvious, but less flame will be pulled into the cat face doing this..
 
I’m just about done burning a cat from Midwest hearth (ceramic made by applied) and have a new one from Midwest to put in. Both bought through amazon. Got the expected 12000+ hours from it.
 
I've had both and the steel cat clogs much easier than ceramic. I still prefer steel though.
 
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I have steel and some of the combs do clog with ash from to time but not terrible and the cat is easy t get to. I don't have an option for a ceramic so I can't compare. If one was I would try it to compare. I'm sure the steel does knock down the draft more.
 
Here you go Dmitry

Amazon product ASIN B07HCNYSX2
Don't panic about the 1 left. Amazon said there was 1 left for me too and it appeared true. But, a day later, there is now another one and the story of only 1 left is back.

Want to take a pic of that flame deflector for me? Did you go through two cats this season? I seem to get only 2 seasons out of mine. I burn wood as the primary source of heat, but these damn things should last longer. I am hoping the one in there now degraded because it moved or was not installed properly and was to far towards the glass and flames. It was not sitting back on the shelf properly.
 
Here you go Dmitry

Amazon product ASIN B07HCNYSX2
Don't panic about the 1 left. Amazon said there was 1 left for me too and it appeared true. But, a day later, there is now another one and the story of only 1 left is back.

Want to take a pic of that flame deflector for me? Did you go through two cats this season? I seem to get only 2 seasons out of mine. I burn wood as the primary source of heat, but these damn things should last longer. I am hoping the one in there now degraded because it moved or was not installed properly and was to far towards the glass and flames. It was not sitting back on the shelf properly.
I burn full time 24/7 in CT and it's my primary source of heat. I got 3 years out of my original before it crumbled in a middle. The sides were pretty good and undamaged . It lead me to believe that flame impregnation was playing role in it. Last year I got new original FPX one and installed DIY flame protector. No scientific reasoning to hole size and placement , just best bet based on other stoves shields look.
I got something like this on ebay
(broken link removed to https://www.ebay.com/itm/3-16-HOLES-16-GAUGE-304-STAINLESS-STEEL-PERFORATED-SHEET-approx-9-6-1-2/113700615820?hash=item1a7915b68c:g:F4EAAOSwZgxbfuIC)
I cut it to size , bent it 90 degrees, making angle and stuck between front tube and baffle . Fits there perfectly, no tools needed, you can remove to clean cat in seconds and slide it back. I think it makes less fire go straight into cat. I'll do pictures later, at work now.
 
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Here you go Dmitry

Amazon product ASIN B07HCNYSX2
Don't panic about the 1 left. Amazon said there was 1 left for me too and it appeared true. But, a day later, there is now another one and the story of only 1 left is back.

Want to take a pic of that flame deflector for me? Did you go through two cats this season? I seem to get only 2 seasons out of mine. I burn wood as the primary source of heat, but these damn things should last longer. I am hoping the one in there now degraded because it moved or was not installed properly and was to far towards the glass and flames. It was not sitting back on the shelf properly.
Here is the picture
 

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Yeah , you can go with bigger or smaller holes you you want .