Blaze King - King Ultra Catalyst Temp Too Hot

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Feb 2, 2012
23
Southern Maryland
I purchased a new King Ultra last March from a guy who bought it the year before but decided he needed an outdoor boiler as the stove wouldn't be enough for his house, so the stove was never installed or used. I installed the stove last week and finally had my first fire Sunday morning. The stove is installed in a masonry fireplace with a single wall liner that runs from the stove nearly straight up a 14' masonry chimney to a stainless cap. I have a decent amount of experience with catalyst stoves but this ones starting to annoy me right now. If I turn the thermostat to 2 the cat will start to run away on me, I can't even imagine what would happen if I had it on 3 or 4. So I've basically been burning only at 1 or 1.5. I should mention that I'm burning 3 year seasoned White Oak that currently has a moisture content between 10 and 16%. When I load the stove I've been alternating the stacking so it's 3 splits tall that cris crosses, going to try not doing that tonight, but wanted to get some recommendations from the King users? This stove will run unattended for up to 14 hours a day and I really want to make sure that I don't overfire the catalyst. I've caught it overfiring twice now in the last 24 hours when I had the thermostat setting at 2.
 
Where was the probe needle? Got a pic of that, and of the cat glowing?
 
What makes you think the cat was overheating? This isn't a buck, you don't need to worry about the cat temps if your door gasket is tight. The cat meter is only provided so that you know when to engage the cat.

Your chimney doesn't quite meet the current spec for the king. Is that 14' liner an 8" liner? Any interior stove pipe with bends or did you just hook the liner to the stove directly? Shouldn't matter though for your issue at hand.
 
What makes you think the cat was overheating? This isn't a buck, you don't need to worry about the cat temps if your door gasket is tight. The cat meter is only provided so that you know when to engage the cat.

Your chimney doesn't quite meet the current spec for the king. Is that 14' liner an 8" liner? Any interior stove pipe with bends or did you just hook the liner to the stove directly? Shouldn't matter though for your issue at hand.

It is an 8" liner that connects straight to the stove but has about a 15 degree bend going into the stove.

Woody - the needle on the cat probe was a 1/3" past the "Active" zone on the probe. I really wish the probe had temperatures on it like my Buck 91 cat probe, I'm a details guy. No idea what that temp would equate to but I would imagine it was over 2000F. If it happens again I'll try to aim the infrared scanner thermometer at the cat and get a reading.
 
It is an 8" liner that connects straight to the stove but has about a 15 degree bend going into the stove.

Woody - the needle on the cat probe was a 1/3" past the "Active" zone on the probe. I really wish the probe had temperatures on it like my Buck 91 cat probe, I'm a details guy. No idea what that temp would equate to but I would imagine it was over 2000F. If it happens again I'll try to aim the infrared scanner thermometer at the cat and get a reading.

Oh yeah, on a new cat you can easily go past the active zone. SOP.
 
With the BK's loose the idea that the cat probe can tell a story about temps, the cat probe is only good for when to shut the by-pass (active zone) because of the t-stat the bk will not over fire, unless the t-stat is opened all the way (btw, you should burn it that way for at least 30min once a week)
Remember: these stove are not flame show stoves, if you have flames in the box your burning it for high heat and using it like a regular stove, the stove makes its $$ by providing a clean smoldering burn (yes black glass burn) and extracting the most heat due to cat position inside the stove.
As far as the un-insulated liner, you should have an insulated on with at least 15ft minimum height, just keep an eye on it, check for creosote build up near the cap, when the stove is cruising on low burn, your flue temps with be about 200-250deg range.
 
the needle on the cat probe was a 1/3" past the "Active" zone on the probe. I really wish the probe had temperatures on it like my Buck 91 cat probe, I'm a details guy. No idea what that temp would equate to but I would imagine it was over 2000F.
You mean the needle on the cat probe was past the silver "active" zone completely and into the black again, approaching 6 o'clock? :oops: The BK cat probe is a re-badged Condar, and it looks like 1600 would be a needle position of about 4 o'clock on the BK no-numbers dial.
Blaze King - King Ultra Catalyst Temp Too Hot

you don't need to worry about the cat temps if your door gasket is tight. The cat meter is only provided so that you know when to engage the cat.
the cat probe is only good for when to shut the by-pass (active zone)
Yet again, I have to disagree that cat temp is of no concern....and there's another guy that thinks high cat temps could be a problem:
Yes, the catalyst can be destroyed (meaning shortening of its lifespan) in any situation where the combustor get much above 1200F. The actual precious metals, palladium and platinum are adhered to the substrate (both ceramic and stainless) using a wash coat of gamma alumina. Under an electron microscope, the surface of the substrate is somewhat smooth, but the wash coat results in a surface that looks like an English muffin. This process vastly increases surface area and creates some turbulence. When the combustor temperatures reach 1200F, the gamma alumina converts to alpha alumina and flattens out, which means it becomes less effective. Sustained use or multiple use at elevated temps shortens the life of the combustor. After too much of these operating temps, the wash coat will peel away from the substrate and take with it the precious metals.
That said, keep an eye on your cat; If the wash coat isn't peeling and the cat is lighting off readily, and your plume is clean when the cat is "active" and the bypass is closed, then you're OK. If not, there's a warranty on the cat...
 
Agreed 100% ^^^^ you need the probe to continue to monitor the cat temp, it climbs quick with good dry wood, you probably should get one of those, just got to know what length probe you need
Blaze King - King Ultra Catalyst Temp Too Hot
 
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Wrangler what area are you in, what part of somd
 
It is an 8" liner that connects straight to the stove but has about a 15 degree bend going into the stove.

Woody - the needle on the cat probe was a 1/3" past the "Active" zone on the probe. I really wish the probe had temperatures on it like my Buck 91 cat probe, I'm a details guy. No idea what that temp would equate to but I would imagine it was over 2000F. If it happens again I'll try to aim the infrared scanner thermometer at the cat and get a reading.


You have an ir that'll read 2000°? The BK guys have all the cool toys. [emoji20]
 
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As seen above there are condar cat meters with different scales. We have no idea which one of them BK took the numbers off of or even if they have a special spring meter that is even different.

Read the owner's manual for your BK. It does not tell you to operate your stove based on cat temp after engagement.
 
Read the owner's manual for your BK. It does not tell you to operate your stove based on cat temp after engagement.
There are a lot of things the stove manuals don't tell you....but if you read it, your Princess manual tells you about catalyst peeling caused by excessive cat temps. It may not actually tell you to operate your stove to avoid excessive cat temps...you'll have to put two and two together.
 
There are a lot of things the stove manuals don't tell you....but if you read it, your Princess manual tells you about catalyst peeling caused by excessive cat temps. It may not actually tell you to operate your stove to avoid excessive cat temps...you'll have to put two and two together.

As has been mentioned above I've always read that any combustion catalyst has a specified operating range and anything above or below that set range causes damage and reaching temps too hot can destroy the precious metal coating.

Kennyp - Looking back I wish I had bought a double walled liner but at the time I needed a long flexible liner to fish through the stupid heatilator system that was installed in my masonry fireplace when the house was built in 77. With the new BK I used bottle jacks and an oxy/ace torch to cut the entire heatilator out and then build a new support to hold up the fireplace block. Nothing like using a torch in your house, while your in a fireplace that may or may not collapse on you. I think the T-stat only functions by the temperature of the stove, not the temperature of the cat so there's probably a decent delay between the cat running too hot and the stove telling the T-stat to close down because the stove is getting too hot. This is my first BK stove so I'm going through my learning curve right now.

Redyute - I'll look for a 4" long cat probe thermometer, with numbers, as I think that's the length I need. I realize, and others should as well, that the temp accuracy on these probes is relative, probably within 10% of the actual temperature when new and will decay with time.

Woody Stover - My needle was between the 5 and 6 o'clock position and I'm sure it was too hot. I threw 2 small splits on when I got home at 6:30 and needle is between the 3-4 o'clock position right now and the thermostat dial is at 1.5. Nervous to leave this stove alone yet, I don't want

Jetsam - The door gasket is brand new and the door was just installed on the stove Saturday night so I doubt it's an air leak at the door but I will check to confirm, never know.
 
It is a learning curve for reel, I got a high valley 1500 and still learning it, sometimes I can get an 8 hour burn with a full load sometimes I get 6 lol, time will tell
 
Read page 15 cat peeling so what is the correct answer 2plus2=4
 
Read page 15 cat peeling so what is the correct answer 2plus2=4
Good link. This is what I was referring to in Highbeam's Princess manual, page 30 I think?
Blaze King - King Ultra Catalyst Temp Too Hot
He keeps telling everyone not to worry about how hot the cat is, but if I remember right, he called in the warranty on his cat after about 3 yrs...I forget the details of what happened to it.
 
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My needle was between the 5 and 6 o'clock position and I'm sure it was too hot.
You can make a ballpark guess as to how hot the cat might me, just by how bright it is glowing. If it's glowing bright orange, where you can't see the cells of the cat any more, that's hot! :oops: You can also see the cat in the 91 by looking in around the bypass rod hole, but it's hard to see....you need just the right angle.
 
I know it's tough but just burn the stove. The cat will be over-active for a while. If you're running the stat in the normal range everything will be fine. Worst case, the cat has a warranty. ;)

Edit: just remembered newer stats have a different sticker. It sounds like you have a sticker with the proper numbers though. :)

Blaze King - King Ultra Catalyst Temp Too Hot
 
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Fir reference here is a picture of my probe(with numbers).
Blaze King - King Ultra Catalyst Temp Too Hot
 
I purchased a new King Ultra last March from a guy who bought it the year before but decided he needed an outdoor boiler as the stove wouldn't be enough for his house, so the stove was never installed or used. I installed the stove last week and finally had my first fire Sunday morning. The stove is installed in a masonry fireplace with a single wall liner that runs from the stove nearly straight up a 14' masonry chimney to a stainless cap. I have a decent amount of experience with catalyst stoves but this ones starting to annoy me right now. If I turn the thermostat to 2 the cat will start to run away on me, I can't even imagine what would happen if I had it on 3 or 4. So I've basically been burning only at 1 or 1.5. I should mention that I'm burning 3 year seasoned White Oak that currently has a moisture content between 10 and 16%. When I load the stove I've been alternating the stacking so it's 3 splits tall that cris crosses, going to try not doing that tonight, but wanted to get some recommendations from the King users? This stove will run unattended for up to 14 hours a day and I really want to make sure that I don't overfire the catalyst. I've caught it overfiring twice now in the last 24 hours when I had the thermostat setting at 2.
I don't know if this helps,my BK parlor is running at BK's minimum chimney height which says 14 feet,this includes two 45 degree turns ,55 inches from where stovepipe enters stove,and then the two 45's which are combined 18 inches,and a horizontal run of 18 inches then straight up.Now i've never had a problem,yet my thermometer for the cat pegs into the black often,the drier the wood,the higher.Mine settles in at about here after 12 hours,this is this morning elm dry as can be. I wouldn't worry.Mine will bottom itself out if I give it air,watched a fire show last night about two hours on about 5 setting cat probe was in the black.
 
Good link. This is what I was referring to in Highbeam's Princess manual, page 30 I think?
View attachment 190158
He keeps telling everyone not to worry about how hot the cat is, but if I remember right, he called in the warranty on his cat after about 3 yrs...I forget the details of what happened to it.

Again Woody, who has never even seen a BK stove, the stove is engineered to prevent cat overtemp. As such, the user need not worry about such things. This is a far more advanced stove than anything you've run. The cat won't overheat unless something has failed such as the door gasket which is the cause of 95% of cat failures.

The photo you posted says 1800 is the max and then the cat probe meter that rdust posted would indicate that 1800 is way up near the r in condar. If we assume that BK uses the same meter then I can say that I've never seen my cat probe needle that high. But remember, I don't have to worry about that because I bought a better stove.

I did replace my cat last year with a steel cat. I sent the old ceramic one to BK for them to see why it lost efficiency and started letting blue smoke leak by. You've got to realize that I live in a climate with a 9 month burn season. The cat is essentially active for 6500 hours per year at a low/medium stat setting. Cat life is stated to be 10,000 hours by manufacturers (some might say 12000?) which as you may be able to see is less than two years for me. My old cat was likely just used up.

I am not the only one that says to follow the manual.
 
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Fir reference here is a picture of my probe(with numbers).
View attachment 190160

I think I'd like to have a cat meter like that. Not that I would run the stove any differently but because I'd like to know. It's like having a tachometer on a new car. The computer won't let you overrev the engine but it's still fun to watch.
 
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