Cat stoves are no good

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Well now our Alderlea has an approved cat added. What a difference! Purrs like a kitten in this mild weather.
 

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On another thread about a Jotul Black Bear it was mentioned the stove is not a north south burn, but an omni-burning stove. So, I checked out the manual. Well, what do you know, this EPA approved, non-cat stove has TWO controls - main air intake on the door, and a secondary intake for the burn tubes.

Are there other non-cat stoves which operate with two controls? Because if the issue is ease of use this Jotul shoots that argument down, I should think.
 
lol. That is funny REF1. Now the Jotul is a complicated stove. It is strange that nobody has brought that up before. Somehow I've always got the idea when folks are shooting down cat stoves because of the "complication" it is perhaps also trying to run down the soapstone stoves or perhaps running one type down (remember that Woodstock and Hearthstone are the biggies here and Hearthstone does not use the cat). Sometimes there may be some jealousy and sometimes it just might be the old "mine is better than yours" attitude. In the end, it still comes down the fact that there are great stoves made; some use cats and others don't. Both have their pros and cons. Cat or non-cat is only a part of the picture.
 
Dual controls on stoves are pretty common. Most top loaders, regardless of burn technology have a bypass and an air control. On the Quad IR there are 3 controls if you include the bypass. There are also non-cat, steel stoves with two controls. Some have a bypass to allow easy starting + smoke-free reloading and the primary air control. Quad ACT stoves have 2 air controls, one for startup and one for burn rate.

The main "complications" I see with running a cat stove are not the controls. It's making sure nothing is burned that can contaminate the cat, making sure it doesn't get thermally shocked, and engaging it at the right temperature. That's why one is not in our house. There are multiple people running our stove and some can get a bit distracted with other activities at times. For that case, the simpler, the better.
 
ControlFreak said:
The thing that bugs me the most about everburn and cat technology is that the main firebox serves as a smoke generator to feed the combustor or the cat. This means that if you have glass in your door, it's going to be grimy looking along with all other interior surfaces in there. The appearance of the fire is miserable, and you can't tell what's going on in the combustor/cat by looking at the stove like you can with a more common EPA stove with secondaries. I classify everburn and cat in the same category, because they're basically doing the same thing, just that one uses a catalyst. The everburn claims to be non-cat, but uses the same basic technology without the benefit of the catalytic reaction, so getting it to light off is much more difficult, and it goes out easier.

The nice thing about everburn/catalytic technology is that you can have a much more even heat output. A non-cat stove is going to have a 2-4 hour burst of heat output with a long tail of declining temperatures, while the cat can produce a constant heat for much more than 4 hours.
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I have to dis-agree with the statement that a non cat has a 2-4 hour heat burst and a long tail of declining temperatures. My harman TL-300 down draft stove keeps a steady 350-450 stove top temp for hours on end only to decline when most of the wood has been burned up some 12 15 hours later. THe output is solely determined by the primary air adjustment. WHile i do not own a cat stove i can see the reason for buying one,but my harman downdraft non-cat does everything i want it to do and it does it well no matter what time of year. Whether it burning flat out on the coldest day or in shoulder season and 55 degrees outside,my secondaries still work for a clean burn. THe only thing i do not yet know is how long the combustion package will last but i hear its a s long as 10 years. THe main reason i did not buy a cat stove is i was afraid of replacing an expensive CAT on a regular basis.
 
Of course, even if you do not close a bypass for a cat the cat will still ignite and burn gases when the temp hits ignition. You would just be losing some up the flu as well. The same can be said for not watching a non cat and as the fire builds there is no light off of a combustor,but until the air is shut down some, plenty of surging flames and volatiles are going right out of the stove.

In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.
 
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

After a 5-10 minute burn off, I close the bypass, set the tstat and leave 4 cu ft of wood to be dealt with by the stove. Safe, complete and predictable.
 
SolarAndWood said:
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

After a 5-10 minute burn off, I close the bypass, set the tstat and leave 4 cu ft of wood to be dealt with by the stove. Safe, complete and predictable.

Although perhaps I give it a bit longer sometimes (I go by flue temp hitting 500) and I don't have the tstat to set (bummer for me) so I just set the air somewhere between .5 and .75, it is about the same here. I consider it quite safe (packed load or partial fill) and I get a complete burn down to minor coals/ash if I don't reload.

Perhaps this is another advantage of well designed cat stoves over non-cat stoves? Less babysitting a full load? I don't treat full loads any different than partial loads in terms of how I operate the stove. I was under the impression that with burn tube non-cat stoves that you basically did the same thing (with the obvious exception of the cat engagement) am I wrong here?
 
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

If the CAT is still lit from the previous load then WHY NOT?
I am able to do this every time. Give or take 10 minutes to get the new load blazing.
 
Slow1 said:
SolarAndWood said:
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

After a 5-10 minute burn off, I close the bypass, set the tstat and leave 4 cu ft of wood to be dealt with by the stove. Safe, complete and predictable.

Although perhaps I give it a bit longer sometimes (I go by flue temp hitting 500) and I don't have the tstat to set (bummer for me) so I just set the air somewhere between .5 and .75, it is about the same here. I consider it quite safe (packed load or partial fill) and I get a complete burn down to minor coals/ash if I don't reload.

Perhaps this is another advantage of well designed cat stoves over non-cat stoves? Less babysitting a full load? I don't treat full loads any different than partial loads in terms of how I operate the stove. I was under the impression that with burn tube non-cat stoves that you basically did the same thing (with the obvious exception of the cat engagement) am I wrong here?

Your right, I also have found less baby sitting and air control tweaking with my cat stove on full loads. I'm thinking the non cat burn tube style stoves have that fixed secondary air hole that can cause the stove to be less controllable at times of high off gassing of the load. You would think a t-stat would be a good thing for a non cat for more control but maybe it's not possible for a clean EPA burn?
 
Todd said:
Your right, I also have found less baby sitting and air control tweaking with my cat stove on full loads. I'm thinking the non cat burn tube style stoves have that fixed secondary air hole that can cause the stove to be less controllable at times of high off gassing of the load. You would think a t-stat would be a good thing for a non cat for more control but maybe it's not possible for a clean EPA burn?

All ya gotta do is plug those un-restricted EPA primary air holes and they purr like a kitten. Load it, get to four hundred and close the air down to 3/4 closed and let it cruise up to five fifty to six hundred. Me and the neighbors with non-cats now do it all the same way and don't go to bed dreaming of cat stoves. Or worry about smoke.

Everybody just needs to burn in whatever they wanna burn in. It's all good.
 
Todd said:
Slow1 said:
SolarAndWood said:
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

After a 5-10 minute burn off, I close the bypass, set the tstat and leave 4 cu ft of wood to be dealt with by the stove. Safe, complete and predictable.

Although perhaps I give it a bit longer sometimes (I go by flue temp hitting 500) and I don't have the tstat to set (bummer for me) so I just set the air somewhere between .5 and .75, it is about the same here. I consider it quite safe (packed load or partial fill) and I get a complete burn down to minor coals/ash if I don't reload.

Perhaps this is another advantage of well designed cat stoves over non-cat stoves? Less babysitting a full load? I don't treat full loads any different than partial loads in terms of how I operate the stove. I was under the impression that with burn tube non-cat stoves that you basically did the same thing (with the obvious exception of the cat engagement) am I wrong here?

Your right, I also have found less baby sitting and air control tweaking with my cat stove on full loads. I'm thinking the non cat burn tube style stoves have that fixed secondary air hole that can cause the stove to be less controllable at times of high off gassing of the load. You would think a t-stat would be a good thing for a non cat for more control but maybe it's not possible for a clean EPA burn?
This has not been my experience with my first non-cat secondary tube stove. Toss in a bunch of wood on the coal bed and shut the door. Wait 5 minutes for good flame. Dial the air back. Forget it for 8-10 hours. Repeat. No extra fiddling with the air control at all. The stovetop rises to 500 quickly, then settles in at 550=600 for hours, then slowly drifts back down once the wood has fully outgassed and there's nothing but coals. Don't need to tweak anything to stay "in the zone".

My experience with a (poorly designed?) cat stove was the opposite. Some days it was fine, but some days needed constant fiddling with the air control for hours after a reload, trying to maintain stable operation without overfiring or backpuffing, which happened often whenever the wood was still outgassing but the thermostatically-controlled primary air would close it off enough to lose all flame in the firebox. Once that happened, it was only a matter of minutes until ignition of the built-up gases and a minor explosion in the firebox, which would just increase in intensity with each cycle until I intervened. No way out of this without opening the bypass for a little while to re-establish flame in the firebox and trying once again to get it stable with the bypass closed, only to be defeated once again by the thermostat's adjustment of the incoming air below that necessary to maintain flame.

The main point being that generalizations about cat vs. non-cat are probably not very reliable. I'm sure there are very well-designed cat stoves that would have run beautifully in my installation. From some comments by others, there are apparently non-cat stoves that require babysitting to keep the temperature where you want it. I have happened to have neither of these in my personal experience, but two models of stove out of the hundreds that have existed is not enough data to make broad comments about all cats vs. all non-cats.
 
Slow1 said:
SolarAndWood said:
REF1 said:
In the end, no stove can be left unattended with a new large load of wood in it. Not for safety. Not for a complete burn.

After a 5-10 minute burn off, I close the bypass, set the tstat and leave 4 cu ft of wood to be dealt with by the stove. Safe, complete and predictable.

Although perhaps I give it a bit longer sometimes (I go by flue temp hitting 500) and I don't have the tstat to set (bummer for me) so I just set the air somewhere between .5 and .75, it is about the same here. I consider it quite safe (packed load or partial fill) and I get a complete burn down to minor coals/ash if I don't reload.

Perhaps this is another advantage of well designed cat stoves over non-cat stoves? Less babysitting a full load? I don't treat full loads any different than partial loads in terms of how I operate the stove. I was under the impression that with burn tube non-cat stoves that you basically did the same thing (with the obvious exception of the cat engagement) am I wrong here?

Ummm . . . not the case for me . . . I'm like you (only with a secondary burn stove) . . . I also rarely fiddle with the air control once I have the fire up and running.

On a reload I may open the air up all the way . . . once the temps are hot enough (generally I too go by the flue temp now that I have the slab of soapstone on top . . . well that and after two years you get a feel for when you should move the air lever) . . . I'll shut the air down to the quarter mark or less . . . and then sit back and enjoy the show. I used to turn down the air in quarter mark increments every 5-10 minutes . . . and still recommend that folks do this . . . but once you've got a well established fire (or rather coals) and your wood is truly seasoned you really don't have to fiddle around with the air much . . . the exception perhaps being on a cold start where you don't already have a nice bed of coals and may want to shut things down in quarter mark intervals.

Generally speaking I do the same thing whether I have the firebox filled to the gills or just loaded up halfway . . . and in every case so far the results have been the same . . . the difference being the fire lasts longer and produces more heat overall with a full load vs. a partial load . . . I still get the secondaries firing off . . . and the temps still say in the Goldilocks Zone (not too hot, not too cold).
 
grommal, I can understand why you had problems with that stove you had. I always tend to mistrust the thermostatically controlled wood stoves and it sounds as if that is where your problem was. For sure if I had to be at the stove controls like that I would have had a sour taste in my mouth. However, as Todd stated, the Fireview is not like that. Once you turn the cat on and adjust the draft, it is basically forget the stove for hours as it will burn nicely. Even if the fire gets to the smoldering stage it will do just fine as the cat can do all the burning with the smoke then. I do open the draft though once it get down to almost all coals which will hold the temperature up and burn down the coals at the same time.
 
Well my prior non cats all had problems trying to find that sweet spot for low long burns. Sometimes the secondaries would peter out and other times they flamed too much. It seemed like I was always adjusting the air. I guess it could of been a draft problem but I have the same setup now that I did with my previous Hearthstone and now like Dennis says it's pretty much set and forget. Not trying to flame you non cat guys, this is just my experience.
 
Todd said:
Well my prior non cats all had problems trying to find that sweet spot for low long burns. Sometimes the secondaries would peter out and other times they flamed too much. It seemed like I was always adjusting the air. I guess it could of been a draft problem but I have the same setup now that I did with my previous Hearthstone and now like Dennis says it's pretty much set and forget. Not trying to flame you non cat guys, this is just my experience.

The answer for me was to quit trying to run a non-cat like a cat and forget about secondary burn. You might notice that not one stove manual says "Get it ripping and slam the air shut and watch the light show."

Since I quit trying to do that stuff I have a hot stove, nice flames in the firebox, long burns and no smoke with a clean chimney. And a lot nicer fire to look at to boot. Load dry wood on hot coals, let the wood catch for ten minutes or so and set the primary air to 25% and go back to my rat killin. In fact on the odd occasion when the gas burner act starts up at the burn tubes it irritates me.
 
I am lucky enough to have a chimney system that will pull just hard enough to give a good, clean, hot, and longish burn with the primary air fully close on my non-cat. This means that I can shut her off and I know that it will burn down safely nomatter the fuel load.

I think that the cat stove, once you get all the levers thrown at the right times in the beginning, will give you more burn time without messing with the stove. A more even heat for longer. Non-cat stoves may have less and simpler controls but the performance nod will go to the good cat stoves.
 
have you all checked any of the upcoming epa mandates? Its got VC going pretty bad... they have found a way to install a slim CAT on top of the everburn system in the new defiants... Word on the street is that many cos will be integrating a CAT one way or the other (horrible move, IMHO) into their 2ndry burn systems, because the CAT is (and always was) a test lab wonder to pass thru the tougher new mandate.. but like any system can be misused and/or innefective in the field
 
summit, are there details on the new mandates anywhere?
 
In reading replies, I have to rest my case. NO STOVE can be left unattended with a full load. Whether it is after 5, 10, 15 minutes, whatever the user decides, you have to shut it down to some degree or you have over-firing. So what is the difference between shutting down an air control to cruise on a non cat, versus shutting down your bypass and air when a cat hits 500? This is really kind of silly and drenched in semantics. Every stove owner looking to understand their stove will work with it to find sweet spots for optimum burning of fuel. I just fail to see the efficacy in any argument which says a cat is more difficult to run than a non-cat.

I have never driven a stick shift. Always had automatic transmission vehicles. Sticks seem incredibly difficult to drive, yet I know people who are so used to it they do it in their sleep.

In the end it's about dealing with a learning curve for any wood stove. My first and only, simple to run, one control non-cat Homestead gave me fits for three months. The Hybrid Elm puts a smile on my face. For me, it's no contest on which is easier to run and which stove performs better.

"To each his own."
 
summit said:
have you all checked any of the upcoming epa mandates? Its got VC going pretty bad... they have found a way to install a slim CAT on top of the everburn system in the new defiants... Word on the street is that many cos will be integrating a CAT one way or the other (horrible move, IMHO) into their 2ndry burn systems, because the CAT is (and always was) a test lab wonder to pass thru the tougher new mandate.. but like any system can be misused and/or innefective in the field

Boy, if VC is worried about their Defiant stove that only burns .75gph, I wonder how low the new EPA numbers will be?
 
REF1 said:
So what is the difference between shutting down an air control to cruise on a non cat, versus shutting down your bypass and air when a cat hits 500?

I just fail to see the efficacy in any argument which says a cat is more difficult to run than a non-cat.

So there you go, one step for the non-cat and three steps for the cat stove with one of them being a variable depending on the user reading a thermometer. Three times as complicated to run a cat stove. Open your eyes man.
 
Highbeam said:
REF1 said:
So what is the difference between shutting down an air control to cruise on a non cat, versus shutting down your bypass and air when a cat hits 500?

I just fail to see the efficacy in any argument which says a cat is more difficult to run than a non-cat.

So there you go, one step for the non-cat and three steps for the cat stove with one of them being a variable depending on the user reading a thermometer. Three times as complicated to run a cat stove. Open your eyes man.

VC Intrepid Cat Stove: Lever to engage Cat, Air Control Lever. Total: 2

VC Vigilant Non Cat: Vertical/Horizontal Burn Lever, Air Control Lever, Pipe Damper Control. Total: 3

Hearthstone Heritage Non Cat: Air Control, Pipe Damper Control. Total: 2

Please point out which stove is more complicated to use.
 
LOL. This is silly.

Highbeam, would you have us believe non-cat owners do not observe their stove and pipe thermometers? For those who operate their stoves with their "eyes closed," we salute you. Those of us who enjoy a catalytic stove do have our eyes open.
 
precaud said:
summit, are there details on the new mandates anywhere?

I'm gonna try to find some. The HPBA trade mag had some charts, but I have been unable to locate it at the shop, and a google search does not find me any hard #'s... But the trade mag did say it had the potential to put many stove co's under because of the stricter mandates: new testing, retrofits, new UL listings, etc. think cali style emissions regs, no burn areas, etc.. The owner of Husdson River stoves was in a few weeks ago (we buy alot of pipe from their distribution co) and he was all worked up about it. 2014 was the target date for these, I believe.
 
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