Steel catalytic combustor for a Blaze King Ultra.

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He said it was dieselfoil. I think in a wood stove application, dieselfoil substrates do not have muti-year life expectancies for full time burners. Durafoil is the substrate we're thinking of when we say 'steel cat'.
 
He said it was dieselfoil. I think in a wood stove application, dieselfoil substrates do not have muti-year life expectancies for full time burners. Durafoil is the substrate we're thinking of when we say 'steel cat'.
Deiselfoil combustors should NEVER be used in solid fuel heating. Industry learned this 5+ years ago. They just cannot handle the temps and expansion/contraction rate exceed allowable tolerances.
 
Deiselfoil combustors should NEVER be used in solid fuel heating. Industry learned this 5+ years ago. They just cannot handle the temps and expansion/contraction rate exceed allowable tolerances.

I assume it was "Diesel Foil" based on information and pictures in this thread. It was supplied with the new stove. Life expectancy was stated to be at least 7 years (if I remember correctly).
The steel "combusters" were nearly useless after the very first burn. Woodstock were 100% behind the product and sent me another steel combustor. The second time I made sure to get some firewood from my neighbor. It was the same firewood he was burning in his Keystone stove and had no combustor issues with his stove. His catalyst glowed red and put out lots of heat. He even tried burning "green" wood and still got the combustor to work just fine. Mine could barely get over 300 degrees on top of the stove, with dry wood. I checked all clearances, looked for air leaks. everything checked fine. Like I said, once I installed the ceramic combustor, it was a totally different stove. The difference was amazing.
Now i need to decide if i need to order a new/improved steel converter or to pay a bit more and get an aftermarket ceramic unit. Any advice will be appreciated.
 
Now i need to decide if i need to order a new/improved steel converter or to pay a bit more and get an aftermarket ceramic unit. Any advice will be appreciated.

Steel and ceramic both work fine.

Lights off faster at the start of the burn: Steel
Stays active longer at the end of the burn: Ceramic
Less prone to plugging: Ceramic
Practically immune to thermal shock: Steel

Pick your poison- just don't pick dieselfoil.

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Steel and ceramic both work fine.

Lights off faster at the start of the burn: Steel
Stays active longer at the end of the burn: Ceramic
Less prone to plugging: Ceramic
Practically immune to thermal shock: Steel

Pick your poison- just don't pick dieselfoil.


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Excellent post, but I suspect that “stays active longer at the end of the burn” verdict is just one of those heresay things that get passed on down the line, and eventually accepted as valid. In theory, the added mass of a ceramic combustor may keep it up to active temperature a bit longer, in a situation when the steelcat might fall out of active temperature range. However, the numbers we’re comparing here are so small that this theory likely does not translate into any significant practical difference. Certainly not enough to even consider a factor, in light of the other three more substantial factors you list.

The same is not true on the front end of the burn cycle, though. There the temperature difference between hot fire and cold cat is substantial, and heating is happening at a very rapid rate. There is a very notable difference in the time it takes to get a steelcat up to temperature, versus a ceramic cat, on this short time scale.
 
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On the other hand, a small difference in thermal mass might mean a half hour or hour at the tail end of a 20 hour burn, when temperatures are very slowly creeping from barely active to barely inactive.

However, the wood is long since done offgassing at that point, and whether the cat is active may not matter in terms of heat production.

I guess that one might be in 'who cares' territory for most of us either way.
 
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Let me bump this thread, if you guys don't mind.
Finally the ceramic combustor (that I mentioned in the previous posts) has failed. As I said in previous posts, my experience with the Woodstock OEM stainless, "diesel foil" combustors was very negative but I was willing to try their new Durafoil combustor. It turns out that they have none in stock. The manufacturer they used, failed to supply them with what they wanted but the new manufacturer has been struggling to make an acceptable product.

I had no choice but to order two ceramic elements required for my Woodstock Fireview wood stove for a total of $200 plus $8 for a gasket. I bought it from FireCat. They claim to manufacture high quality elements but I have some doubts after unpacking and inspecting the elements. The "wash" with the precious metals was applied very unevenly. There is none inside the ceramic tubes. Most of the catalytic metals were applied to the element edges that will never be exposed to the gases because it's where the gasket goes. Perhaps i expect too much from a stove catalyst manufacturer but I'm beginning to really doubt my decision to purchase the Woodstock Fireview stove. There are too many design flaws in the product that has been on the market for so long.
I have really been considering to sell the Fireview and get a Jotul non-catalytic stove. I won't have to worry about uneven burn in the Fireview due to poor combustion air distribution and I'll be able to burn the Jotul continuously. The Fireview has no ash pan and can only be used for several days before it gets full of ash. It's a beautiful stove but such a pain in the arse to use.
 
Lack of satisfactory cat suppliers is a serious problem.This is a wearing part. Did you consider other cat suppliers like Condar? Keep us posted on how the Firecat works out, maybe in a new thread.
 
Lack of satisfactory cat suppliers is a serious problem.This is a wearing part. Did you consider other cat suppliers like Condar? Keep us posted on how the Firecat works out, maybe in a new thread.

Yes but Woodstock recommended to buy from FireCat. FireCat claim to be experts in producing quality combustors with a long warranty. I wonder how I would claim the warranty if it does not perform? They will most likely tell me I don't use it correctly and I need to burn wood with zero moisture, just like what Woodstock told me. Where the heck can I find perfect wood? It's nearly impossible and highly impractical.
 
Perfect wood should be just about any species that is <20% inner moisture. The time it takes to season will depend on the species.
 
Let me bump this thread, if you guys don't mind.
Finally the ceramic combustor (that I mentioned in the previous posts) has failed. As I said in previous posts, my experience with the Woodstock OEM stainless, "diesel foil" combustors was very negative but I was willing to try their new Durafoil combustor. It turns out that they have none in stock. The manufacturer they used, failed to supply them with what they wanted but the new manufacturer has been struggling to make an acceptable product.

I had no choice but to order two ceramic elements required for my Woodstock Fireview wood stove for a total of $200 plus $8 for a gasket. I bought it from FireCat. They claim to manufacture high quality elements but I have some doubts after unpacking and inspecting the elements. The "wash" with the precious metals was applied very unevenly. There is none inside the ceramic tubes. Most of the catalytic metals were applied to the element edges that will never be exposed to the gases because it's where the gasket goes. Perhaps i expect too much from a stove catalyst manufacturer but I'm beginning to really doubt my decision to purchase the Woodstock Fireview stove. There are too many design flaws in the product that has been on the market for so long.
I have really been considering to sell the Fireview and get a Jotul non-catalytic stove. I won't have to worry about uneven burn in the Fireview due to poor combustion air distribution and I'll be able to burn the Jotul continuously. The Fireview has no ash pan and can only be used for several days before it gets full of ash. It's a beautiful stove but such a pain in the arse to use.

Wow! First very unhappy FV user I've heard of? Sounds like you've had a less than stellar Woodstock experience? Very contrary to most reports.

Doubt you will have much luck "finding perfect wood". Hopefully you can gather enough to let it set a few years before use. It will likely change your entire burning experience if you are currently burning less than optimal fuel. The FV isn't alone by a long shot with dry wood requirements. I'd venture a guess you will have a hard time getting any modern stove to perform without it. Jotul included. Should be interesting to hear how the new Firecat works. Good luck!
 
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There are too many design flaws in the product that has been on the market for so long.

What design flaws are you referring to? Also what is your chimney setup - how tall and is it lined?

I had a FV with the ceramic combustor. I burned 24/7 over the heating season and got about 3 years out of each Cat. I had big problems the first year because I did not understand the importance of dry wood but it sounds like you were happy with the ceramic cat. I never had a SS cat in that stove but the Palladian does and it behaves great.
 
Durafoil combustor. It turns out that they have none in stock. The manufacturer they used, failed to supply them with what they wanted but the new manufacturer has been struggling to make an acceptable product.
I read here recently that Woodstock is taking steps..I thought the post said something about them wanting to do some of the assembly work in-house?
The DuraFoil I have in the Keystone right now is working great. I also got a second one, since I had to wait for the first one..wanted another backup in stock. I also have the original ceramic, which is working OK last time I used it. I've been swapping back and forth so I'm not sure how many hours are on each one.
I had no choice but to order two ceramic elements...I bought it from FireCat. They claim to manufacture high quality elements but I have some doubts after unpacking and inspecting the elements. The "wash" with the precious metals was applied very unevenly. There is none inside the ceramic tubes. Most of the catalytic metals were applied to the element edges that will never be exposed to the gases because it's where the gasket goes.
I ordered a ceramic from them as well, for the Buck 91, and saw the same thing, except it wasn't sprayed on the edge that I noticed since the cat was "canned" in a stainless shell. You can see some inside the cells in this pic, but a lot of other areas, it wasn't in the cells, just on the face. The combustor worked fine though, so I guess they get enough on there for it to work for the specified time. Put it in and run it.
If you look at the warranty, I think it is 100% replacement cost for the first three years, then pro-rated from 3-6 yrs. I've been replacing mine at about three years, when performance starts to drop off noticeably.

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uneven burn in the Fireview due to poor combustion air distribution and I'll be able to burn the Jotul continuously. The Fireview has no ash pan and can only be used for several days before it gets full of ash. It's a beautiful stove but such a pain in the arse to use.
Well, I'm not a big fan of shoveling ashes either, and went from the Fireview to the Keystone to get the ash grate and bigger window. You could make that switch, provided the Keystone will handle your house sq.ft. It is a notch down in output from the Fireview.
What you mean by an "uneven burn," though. I didn't have a problem in that regard. What exactly are you seeing that you don't like as the load burns down?
And what do you mean by "I'll be able to burn the Jotul continuously?"
 
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They claim to manufacture high quality elements but I have some doubts after unpacking and inspecting the elements. The "wash" with the precious metals was applied very unevenly. There is none inside the ceramic tubes. Most of the catalytic metals were applied to the element edges that will never be exposed to the gases because it's where the gasket goes.

I'm running a firecat ceramic combustor right now, it's about at half of the expected life. The OEM was a firecat ceramic, then I went steel, and now back to firecat ceramic. They've been great and inexpensive from firecat.

I wonder if the color of the cat element has anything to do with the evenness of precious metal application. Perhaps you're assuming too much there. Throw it in and give it a try, you probably will see a very even light off and glow despite the inconsistent color of the unused combustor.

I have been burning full time since late September and only have about 1.5" of ash on the bottom of the firebox. Haven't emptied it at all this year. Ash accumulationhas a lot to do with the species being burned.
 
I'm running a firecat ceramic combustor right now, it's about at half of the expected life. The OEM was a firecat ceramic, then I went steel, and now back to firecat ceramic. They've been great and inexpensive from firecat.[/QUOTE

which one ya like the best?
 
which one ya like the best?

I will definitely be buying another ceramic when this one wears out. Much cheaper, just as effective, less likely to clog, maybe even less restrictive. Cheaper is the biggest reason. No downside. Even BKVP runs a ceramic!
 
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how about the ashford? steel or ceramic? Also I've wondered why BK used steel in one and ceramic in the other
 
how about the ashford? steel or ceramic? Also I've wondered why BK used steel in one and ceramic in the other

I would love to have an ashford! When I switched to a BK so many years ago, they only had the ugly BKs and only required 12' of chimney! The ashfords were only ever were made with steel cats. Seems to be a common theme with the newest stove models from Woodstock too. Anyway, @Ashful was able to replace the OEM steel with a ceramic in his ashford so he can maybe offer some advice.
 
It had been mentioned in the past inconsistencies in color of the brand new cats didn’t mean the wash coat was applied uneven, or considered defective.
 
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It had been mentioned in the past inconsistencies in color of the brand new cats didn’t mean the wash coat was applied uneven, or considered defective.

X2, this has been covered here before.
 
The Woodstock Fireview is (or at least was, at one time) one of the most popular catalytic stoves on the market, and you won’t find many complaints about them, they’re one of the top performers of their time in all regards.

I am wondering how you are evaluating the application of the wash coat, do you have your own spectrometer? I wouldn’t assume the appearance is a way to determine this, but perhaps a manufacturer (@BKVP is one of our experts here) can enlighten us, can one evaluate the coverage of the wash coat by appearance alone?

I have only seen two complaints ever lodged against the Fireview, with any frequency, in all of the tens of thousands of posts I have read on this forum:

1. They might be prone to back-puffing at the lowest burn rate on shorter chimneys. A few users have had that issue, but unfortunately the one that was most prolific on the subject was deleted from the archives.

2. They have or had a screen upstream of the combustor, which tended to clog with fly ash. It was always reported as something simple to clean, but caused much frustration for the few users experiencing it. I suspect these might have been users with unusually tall chimneys, high draft condition.

Aside from that, the Fireview is likely one of the most trouble-free and beloved stoves ever made. If you’re unhappy with it, it’s unlikely you’re going to find another stove with fewer issues. All stoves are a compromise, in one aspect or another, choose yours accordingly.
 
It had been mentioned in the past inconsistencies in color of the brand new cats didn’t mean the wash coat was applied uneven, or considered defective.
In the pic I posted above, it was obvious when observed first-hand, that the ceramic was all one color, no variation, and the catalyst was the stuff that appeared to be sprayed on. I didn't read that previous post about this, and who made those combustors. Both our combustors came from firecat so I'm assuming that he is seeing what I saw. I guess in some cases, the wash coat (what is applied to the ceramic so that the catalyst can stick to it) may have color variation. I didn't see that on the firecats though..
I have only seen two complaints ever lodged against the Fireview, with any frequency, in all of the tens of thousands of posts I have read on this forum:
1. They might be prone to back-puffing at the lowest burn rate on shorter chimneys. A few users have had that issue, but unfortunately the one that was most prolific on the subject was deleted from the archives.
2. They have or had a screen upstream of the combustor, which tended to clog with fly ash. It was always reported as something simple to clean, but caused much frustration for the few users experiencing it. I suspect these might have been users with unusually tall chimneys, high draft condition.
You can pretty easily run the Fireview on 13.5' of stack, which is what my BIL has on my old stove. He had one back-puff, and as far as I could determine, he cut the air too far, too soon before he had the load burning well, and it was 50* out. I never had a back-puff when I ran it here on 16', even when warm out. You do have to get the load burning and the cat cranking first, though.
I have/had the screen on both my Keystone and the Fireview. You need to brush it every couple months at least, but I usually do mine once a month. I just reach in the box after the stove has burned down with a chip brush, an old toothbrush or whatever and brush off the screen. Nothing to take apart, easy as pie. If it causes you "much frustration," you may have some sort of problem with your brain. ;lol
I assume it could clog faster with high air settings, but the highest I ever run is with a small amount of flame in the box, with the air set around 1 on a scale of 4. It's not stirring up any ash.
The ash is carried up to the screen by flame as the wood burns. With a cat-only burn, maybe when the wood "pops," some ash is carried up. Or when I stir a poker through the ash to let it fall through the grate into the ash pan, a small amount is stirred up. You can't see it, so it ain't much. With the door and bypass open though, most of that small amount of dust is headed up the flue.
 
You cannot see the catalyst (palladium and platinum). You can see wash coat. In 25 years I have yet to see a ceramic combustor where the color was uniform. There is, to the human eye, no way to predict combustor performance based upon color/pattern.

I will admit if you see one that is completely white...it probably does not have any application of wash coat (which carries the precious metals)
 
You cannot see the catalyst (palladium and platinum). You can see wash coat. In 25 years I have yet to see a ceramic combustor where the color was uniform. There is, to the human eye, no way to predict combustor performance based upon color/pattern. I will admit if you see one that is completely white...it probably does not have any application of wash coat (which carries the precious metals)
OK, so the wash coat has the catalyst mixed in, and then it's sprayed on, as seen in my pic above? It was mostly white, only brown on the face, with some spray down into some of the cells. If you look closely, you can see that some cells have no catalyst/wash coat inside them at all, and are white down in there.
So now I'm thinking that even though the catalyst isn't coating anywhere near all of the ceramic, once the catalyst starts burning smoke, the rest of the ceramic will get hot and eventually glow, even though it may have no catalyst on it. And if the ceramic is 1000-1500* and glowing, it is burning the smoke inside the cells, even though there's no catalyst in there..?
 
OK, so the wash coat has the catalyst mixed in, and then it's sprayed on, as seen in my pic above? It was mostly white, only brown on the face, with some spray down into some of the cells. If you look closely, you can see that some cells have no catalyst/wash coat inside them at all, and are white down in there.
So now I'm thinking that even though the catalyst isn't coating anywhere near all of the ceramic, once the catalyst starts burning smoke, the rest of the ceramic will get hot and eventually glow, even though it may have no catalyst on it. And if the ceramic is 1000-1500* and glowing, it is burning the smoke inside the cells, even though there's no catalyst in there..?
I'm interested in this as well.