Cat vs Non-Cat: Flame show only

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SculptureOfSound

Feeling the Heat
Sep 9, 2017
372
Wisconsin, USA
Hi guys,

I know cat vs non-cat has been done to death but despite that, and scouring the previous battlegrounds threads, I couldn't really find much on the flame show differences in each.

I'd love it if this thread could focus ONLY on the flame show aspects of the two different technologies and maybe become the definitive thread on this topic, as this aspect of the debate has just gotten lost in other cat vs non-cat threads. Would also love to see people post videos of their stove/insert and its flame show!

There was this back and forth in another thread that raised some questions:

I guess the only thing I would add aside from all the details that I've read cat vs noncat is what is wood burning to you. Heat or Heat/Fire. I personally like seeing the fire like a traditional fireplace. The secondary burn is mesmerizing to just sit on the couch and enjoy. I love the thought of a no hassle load and forget cat stove, but it would really just be a house heater if I wasn't seeing the flames, which makes it as exciting as the kitchen stove- another appliance for me. I wanted a more efficient fireplace than the open chimney, but I still wanted to see the fire blazing in the living room and thats what I got. If I were doing it again right now, I would have already ordered the Progress, best of both worlds, on sale, and beautiful imo.

Well if this is the case a cat stove would be more appropriate. A cat stove has all the flames you want until you decide to turn it down for a low burn, on a medium burn it will have some very nice natural looking flames with some light off around the cat happening. I was under the impression I would lose a view of the fire by switching to a cat stove but that's not the case. The tube stove I burned didn't resemble a fireplace fire in any way, it looked like a gas grill burning. :) I really thought I would miss the fire from a tube stove, I haven't missed it in the least, I usually load the stove burn it hot for 10-15 minutes and then turn it down to the point where the flames get lazy and let it burn until I decide to turn it down for the night.

Its not you directly, more the argument of both- In a previous post where I said I went with a tube stove for the flames of a traditional fire and was responded to with cat stoves are also capable of flames of a traditional fire/ or better at it etc: I think thats misleading someone in the market for either. I'm operating my stove at a comfortable temperature any day of the winter while sitting down at any point to enjoy a fire. Same situation with a cat stove seems to be operating it at a level higher than what would be comfortable in order to produce flames, otherwise down to 20* it can be kept on low/no flames. Now if I bought a cat stove based off a recommendation that it can do what a tube stove does in the ambiance department I'd be a little ticked off because of that operating difference.​

  • Is it true you'd have to run a cat stove hotter to get a similar flame show (as per last paragraph above)?
  • Is the length of flame show different for each, given that you'd be burning either at a medium or high setting (cats obviously won't have much or any show at very low settings)
  • Cat stoves seem to get "dancing secondaries" as the gas ignites, while tube stoves have more of a rolling/gas grill like secondary burn. How long do the secondaries tend to last on each?
  • Is it true that the fire show on a cat stove is actually more open fireplace like due to the lack of intense secondaries?
  • For those who have owned/experienced both, which flame show do you prefer? (excluding all other aspects of stove performance)
 
I'd say the size and type of wood, the way it's loaded and the particular model stove you have (and how it's operated) probably makes for a wider variety of flame types than simply whether it's catalytic or tube type.

But, yeah, in general a tube type is going to show more secondary flames if everything else is similar.
 
+1 on what @WoodyIsGoody said. I have a Buck 94NC and the flame show depends on the kind of wood, how "dry" the wood is, how full we fill it, and where we set the air. We get a pretty cool show from the secondaries and the smoke igniting. As the fire burns down, the show gets less and less (we get about 4-6 hours on a small load depending on the wood). Once the wood is "coaled over," the flame show more or less stops. I generally mix soft and hardwoods so I cannot comment on which gives a better show to watch.
Hope that helps a bit.
 
I own one of each technology. Use the same wood and often have them both running. The fireshow from both is super when they're making moderate heat and higher. You can't turn down a noncat so it pretty much always has flames by design. When I'm too hot or sick of watching flames from the cat stove I have the option of adjusting the output to a low and efficient level where just the glow of coals is visible. If you want flames just leave either stove type cranked up.
 
Fire show varies with the stove design, particularly the baffle design or the cat location/orientation. They are different between a lot of stove. And then some stoves are hybrids and have their own unique flame show (ie the Ideal Steel). The Castine delivered amazing fountains of fire during peak secondary burn. The T6 is more billowy and often wraith-like, particularly as the fire dies down. This has to do with the difference in baffle design and the location/orientation of the secondary holes.
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Several Napoleon stoves have the secondary tubes facing sideways. They have a different light show too. And then there is the Wittus Twin-Fire. That has to be seen (and felt) to appreciate.
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I own one of each technology. Use the same wood and often have them both running. The fireshow from both is super when they're making moderate heat and higher. You can't turn down a noncat so it pretty much always has flames by design. When I'm too hot or sick of watching flames from the cat stove I have the option of adjusting the output to a low and efficient level where just the glow of coals is visible. If you want flames just leave either stove type cranked up.


Do you find the assertion that a cat stove has to be running hotter than a non-cat to get the same amount of flames to be true?

From my understanding it seems like either has to be running on medium or high to have flames, just that a cat can go low and smolder without issue. But if it's true that for equal amount of flames the cat stove has to run hotter that could impact someone's decision whose primary concern is ambiance
 
Begreen that twinfire is amazing. Great vids you posted which really shows a lot of variation. I thought that variation may have been due to just being filled at different times in the burn cycle but it sounds like most of the variation is due to design choices. That T6 flame is hypnotically relaxing
 
The Twin-Fire is the most front radiant stove I have ever experienced. The heat it puts out is very impressive.

There are lots of videos posted on youtube of stoves burning. You might like this one showing the the Ideal Steel's burn, before and after the air is turned down. Make it full screen. The only show for the second half is the cat thermometer needle gradually climbing upward.

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Ah, the 2nd half of that video is what I worry about as I consider the BK insert vs the Quad. Now, if it's true that you get roughly the same amount of flames (maybe excluding secondaries, but just base "flames") from a cat stove at the same output as a tube stove, then all is good and nothing to worry about.
 
Cat stoves can be interesting too, for awhile. I am a bit surprised by the high flue temp in this video.

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I can get a great light show with my Ideal Steel cat hybrid, if I'm not going for the lowest/slowest burn mode. After the cat is engaged and the air shut back, I simply open the air just enough to get those rolling "ghost flames" that fill the firebox for a few seconds. Then the firebox goes mostly black, with just a small wisp of flame flickering here or there, until the next burst of flame fills the window as the gases suddenly reignite. This cycle may repeat many times before the firebox goes black and into cat-only burning.

For my money, it's a far more interesting and mesmerizing show than I even saw with a burn tube stove.
 
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I can get a great light show with my Ideal Steel cat hybrid, if I'm not going for the lowest/slowest burn mode. After the cat is engaged and the air shut back, I simply open the air just enough to get those rolling "ghost flames" that fill the firebox for a few seconds. Then the firebox goes mostly black, with just a small wisp of flame flickering here or there, until the next burst of flame fills the window as the gases suddenly reignite. This cycle may repeat many times before the firebox goes black and into cat-only burning.

For my money, it's a far more interesting and mesmerizing show than I even saw with a burn tube stove.

Your observation describes why there are (in general) more secondary flames, more often, with a secondary burn stove vs. a cat stove. Because that cat is not getting red hot without burning something! It's burning the gases that, in a tube stove, are mostly burned in the top of the firebox where you can see them. A cat stove can do that too but tube stoves are designed specifically to encourage secondary combustion so they have the edge in being hot enough at lower burn rates (and having air injection) to produce secondary flames. Every secondary burn stove I've ever operated has been capable of the exact phenomenon you just described. Maybe some are not depending upon the amount of secondary air they meter. I've seen videos of tube stoves that burn more like a natural gas appliance (which is not very dramatic looking or flattering).
 
Do you find the assertion that a cat stove has to be running hotter than a non-cat to get the same amount of flames to be true?

From my understanding it seems like either has to be running on medium or high to have flames, just that a cat can go low and smolder without issue. But if it's true that for equal amount of flames the cat stove has to run hotter that could impact someone's decision whose primary concern is ambiance

It sounds like you, or this hypothetical someone, are interested in flames without heat. I might suggest a video of a yule log or maybe even an outdoor firepit before recommending a purposely inefficient and wasteful appliance just for the sake of more visible flames at lower output levels.

Heck, a pellet stove pretty much always has a flame so that might be a smarter option. They have those electric fireplaces that don't make any heat but shine a glowing red lamp at a screen. Oh, another idea, a nice lava lamp.

I enjoy the fire and heat and efficient use of the wood fuel. I also find that the glowing red pile of coals without flames but with intense heat can be very pleasant.
 
Is it true you'd have to run a cat stove hotter to get a similar flame show (as per last paragraph above)?
Not true. I can have flame show with a burn time up to 12 hours on my 2.65 cu.ft. cat stoves. Let's see ANY 2.65 cu.ft. non-cat run that sort of burn time. Heat output is simply BTU's per hour, and there are only so many BTU's in a fixed load of 2.65 cu.ft. I do lose the flames, when I turn it down much farther than this, but that flexibility to dial it to either mode is the advantage.

Is the length of flame show different for each, given that you'd be burning either at a medium or high setting (cats obviously won't have much or any show at very low settings)
There are likely differences. For example, the 12 hour burn time I outline above has flame show for the initial hours of the burn, which wanes as the load is reduced to coals. At that particular setting, it will sometimes it will die out half way thru, and then flame back up an hour later. Part of the fun, I guess.

Cat stoves seem to get "dancing secondaries" as the gas ignites, while tube stoves have more of a rolling/gas grill like secondary burn. How long do the secondaries tend to last on each?
I thought you liked the look of a fireplace? Secondaries are unnatural, and make a stove look like an inverted gas grill, to me. I don't want to see them.

Is it true that the fire show on a cat stove is actually more open fireplace like due to the lack of intense secondaries?
True.

For those who have owned/experienced both, which flame show do you prefer? (excluding all other aspects of stove performance)
I have owned five stoves, but they've all been cat stoves. My exposure to non-cats is entirely thru friends and visits to dealers. I obviously prefer cat stoves, but flame show is not one of the factors in that preference, just a result of it.

Do you find the assertion that a cat stove has to be running hotter than a non-cat to get the same amount of flames to be true?
Not true. Again, I can have flame show simultaneous with burn times longer than any comparably-sized non-cat. I can also turn it down to have burn times 3x - 4x that of any similar-sized non-cat, albeit without flame show... just turn the knob.
 
It sounds like you, or this hypothetical someone, are interested in flames without heat. I might suggest a video of a yule log or maybe even an outdoor firepit before recommending a purposely inefficient and wasteful appliance just for the sake of more visible flames at lower output levels.

Heck, a pellet stove pretty much always has a flame so that might be a smarter option. They have those electric fireplaces that don't make any heat but shine a glowing red lamp at a screen. Oh, another idea, a nice lava lamp.

I enjoy the fire and heat and efficient use of the wood fuel. I also find that the glowing red pile of coals without flames but with intense heat can be very pleasant.

I wouldn't say I'm looking for flames without heat. The thing is, I do like the look of the secondaries on some stoves/inserts, and not so much on others. With cat stoves, it's harder to find videos that show secondaries at all, and determining how long these are present (or can be sustained, if desired) is almost impossible from the vids out there. Hence all the questions.

When I first moved in I thought I wanted just an open fireplace (having never had one). I couldn't use it to test before relining as the flue tiles were cracked (got the cost of relining knocked off the price of the house). So I got it relined, and... well, don't like it as an open fireplace as it tends to smoke a bit and I get virtually no heat. I should have done a lot more research prior to that decision but there was 9 million things going on having just bought my first house. So, $1k out the window re-lining it, when I'll have to re-line it again for my future insert. I don't want to make that mistake again.
 
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With cat stoves, it's harder to find videos that show secondaries at all, and determining how long these are present (or can be sustained, if desired) is almost impossible from the vids out there.

The cat hybrid stoves like mine are nice, because you can get some variation in the secondaries depending on what mode of burning you are doing. If I leave the air open a good bit, I will get rolling flames and burn-tube secondaries. Shut it back a bit, and then I get the low flames coming off the wood that periodically burst into a "ghost flame" that floats around the firebox for a few moments.

While I enjoy watching these (especially in a dark room) for several minutes, they will not last an extended amount of time, but there is only so much time I want to spend sitting in front of the stove watching flames through the window. So when the light show ends and the stove goes into all-black cat mode, it's no big deal. There will always be another show.

Because you are cut off from the fire by the window, I don't think a stove can ever match an open fire for sitting in front of, since you can feel, hear and smell an open fire as well as see it.

Consider then that you can get a stove that allows for open-door burning on occasion. When I first got a stove, having one with a screen option was a top consideration. But like most, I found that I rarely used it. Viewing the fire through a glass door is neither better nor worse than an open fire, but it is definitely different. I could say the same about viewing fire in a cat (or hybrid) or a non-cat. There was certainly more flame in the non-cat that I had, but it was not always very interesting flame. To me, the shorter light show in the cat-hybrid is a more compelling show, even if shorter.
 
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I wouldn't say I'm looking for flames without heat. The thing is, I do like the look of the secondaries on some stoves/inserts, and not so much on others. With cat stoves, it's harder to find videos that show secondaries at all, and determining how long these are present (or can be sustained, if desired) is almost impossible from the vids out there. Hence all the questions.
You will not typically get extended visible secondaries from a cat stove. On my downdraft cats (Jotuls), the cat was buried behind the firebox, and so you couldn’t see what it was doing, if anything. On the BK’s, it’s atop the firebox, toward the front. I do get exciting secondary action from it, when first turning it down from high to low burn, but it doesn’t last. This is why I say it looks more like the open fireplace you were seeking.

Non-cats can have an amazing gas grill-like secondary show, which cats lack. Cat stoves just have primary flame show, like a fireplace. They lack the artificial gas flame of a tube stove, if that’s what you’re seeking.
 
Beautiful flame like secondary tube stoves it is not the strongest point of a cat stove. If you like that, is better to stay with tube or hybrid stoves. When cat stoves, some are capable of give some beautiful/ghost flame, it is not like tubes. Many times cat stoves don't reach the temp that tubes need for secondary burn take place. Most of the time is just to char the new load and back to dark box. looking just for the continuation of that steady heat to keep our comfort. when burn it hotter, you get some of those nice ghost flame but nothing like tubes plus it is just for a short time compare to tubes.

I will say, Hybrids are good on that department for some that want to have a little of both world. For me i can careless about beautiful flames, but i know is just me and i can see and accept the reality. After all the best stove in the wrong house is/look ugly.
 
you get some of those nice ghost flame but nothing like tubes plus it is just for a short time compare to tubes

Yeah, less in quantity... but in my opinion, higher quality! Burn tube flames get kinda boring, where ghost flames always are amazing to me.
 
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My experience with the BK and the Alderlea stove is that the Alderlea "show" is much better than the BK. Not only are there more flames, but the superior air wash on the Alderlea keeps the glass much cleaner so you can see it better.

The dirty glass is my only complaint with the BK.
 
but the superior air wash on the Alderlea keeps the glass much cleaner so you can see it better.

I think that it can be a mix of air wash and the point of burning hotter, I don't think you can dial the T5 as low as you do with the BK, what make the glass stay cleaner. Maybe I am wrong.
 
I think that it can be a mix of air wash and the point of burning hotter, I don't think you can dial the T5 as low as you do with the BK, what make the glass stay cleaner. Maybe I am wrong.

No ,you are right, the T5 can't burn as low as the BK, but even burning wide open, the BK glass is still dirtier. I clean the white haze off the T5 glass about twice a year and it is run with the air completely closed 95% of the time. I think its just inherent differences in the clean burn technology.
 
I clean the white haze off the T5 glass about twice a year and it is run with the air completely closed 95% of the time

You do realize that you are nowhere near completely closing off the air to the T5? Not only does the primary air intake not close completely but the secondary air system (and possibly dog house air) is rip roaring open!
 
You do realize that you are nowhere near completely closing off the air to the T5? Not only does the primary air intake not close completely but the secondary air system (and possibly dog house air) is rip roaring open!
The secondary air on the mid-sized PE (and Enviro) stoves is coupled to the primary air control. It decreases as the main air is reduced. That's part of what helps this stove have good long burn times and nice fire control. Someone a while back posted a picture of this linkage. jefft?

edit:
an old but good thread on the mid-sized PE air control
https://www.hearth.com/talk/threads...o-you-go-with-the-inlet-air.7863/#post-173519
 
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The secondary air on the mid-sized PE (and Enviro) stoves is coupled to the primary air control. It decreases as the main air is reduced. That's part of what helps this stove have good long burn times and nice fire control. Someone a while back posted a picture of this linkage. jefft?

edit:
an old but good thread on the mid-sized PE air control
https://www.hearth.com/talk/threads...o-you-go-with-the-inlet-air.7863/#post-173519

Oh yes, slamming the primary air control shut on the super stoves reduces the air to both primary and secondary systems but not by much! If the controls reduced air very much then you would lose the clean burning secondary combustion that requires very high firebox temps. If I had to have a noncat in the house, the PE super series would be at the top of the list.

As chimneysweep points out, he gets the fire going and then slams the control to zero but the fire rages on above the 1000 degrees needed to keep a non-cat clean. Quite a lot of air!
 
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