HELP!; Wood Stove out of control

[begreen]

Thanks much for the links. The you-tube video looks exactly like what is happening. This is one of the responses from the video that I might try:
"The problem is caused by depriving a hot fire of air too quickly. We have the exact same problem with our VC defiant. It helps to gradually turn down the air and then close damper. We leave the air valve open 1/3 overnight."

I'm also wondering if my CAT might be clogged a bit. I removed and vacuumed it, but did notice that I couldn't see light shining through a good portion of the honeycomb, when I shined a flashlight through. Does this seem like this could be causing or exacerbating the problem? It's interesting that I believe the CAT is not lighting off as easily as it did a couple of months ago.

That could be a big part of the problem right there. It should be cleaned regularly, approximately after each cord of wood burned.

 

[Battenkiller]

By 'explosions', it appears some smoke suddenly ignites in the main firebox causing a sudden flame and whooshing noise. It also causes smoke to get forced out of the top loading door.
Flames should not hit the combuster directly, as there is a 'throat' (piece of cast iron with holes) protecting the combustor from direct flame.

It seems that I shut the air intake too quickly, the combuster doesn't really get going, which seems to cause excessive smoke buildup in the main firebox. I've been trying to find the optimal point to both close damper and lowering the air control. This stove just seems very finicky about getting it just right.

You are experiencing classic backpuffing explosions caused by excessive combustion gases suddenly igniting. Not enough primary air to completely burn off the gases, so your cat is working overtime to burn them. I'm not familiar with the VC cat internal air flow, but in the old non-cat designs, secondary air comes into the secondary combustion chamber in cycles that are dependent on how much smoke is in the chamber. If the wood is producing lots of smoke, this pre-heated air can cause the gases to explode and you will get an alarming backpuff that comes right out of the secondary air intake hole. I stopped peaking into the hole after I caught one of those right in the eye. Luckily, I wear eyeglasses.

As far as your wood goes, don't let the easy ignition and good heat it it producing fool you. Partially seasoned oak will ignite fine since it is very dry on the outside. And despite the old wife's tale that you get poor heat from less than ideal wood, there is only a very small relative loss in sensible heat production from wood that is higher in moisture content. Over the range of moisture content that wood will actually burn, the total potential loss is, at the most, only 10-15% - not something you'd notice until you inventory your wood supply at the end of the burn season. Despite that fact, it will not burn as clean as drier wood and will make more smoke. In the non-cat design, you simply give it more air to burn it off as it is being formed. In a cat stove, the design calls for the smoke to be burned higher up in the box, outside of the primary burn zone. Too much smoke will not be adequately addressed by the cat alone and it will build up in the box. This is why you need very dry wood for a cat stove.

Yes, get a moisture meter. I checked the cheap HF meter (<$12) against the completely accurate oven-dry testing method and found that it was close enough for firewood. Check the outside of several pieces, then split them in half and measure the inside surface. Total MC will be close to the average of these two readings. Between 18-20% is considered to be ideal. Even without a meter, you can just re-split the wood and hold it against your cheek. If it is not dry enough inside, it will feel cool and moist.

Unless your neighbor happens to be Quads, chances are he hasn't seasoned that oak for the three years necessary to get it down to 20%.

 

[BrotherBart]

Wood is gonna react the same way in a cat or non-cat stove. That being if you stack a load of fresh wood on top of a big hot coal bed when the stove temp is over say around four hundred degrees, all hell is gonna break loose due to the rapid outgassing of the wood. Let that puppy burn down to around three to four hundred stove top temp before reloading and see how it goes.

Thanks, I'll give that a shot.

Theoretically though, wouldn't you want the firebox hotter in order to burn off excess smoke within the firebox?

You want either the flames or the cat to burn the smoke. It ain't a diesel engine where you want it burned by exploding from the heat and pressure. Once that cat is doing its thing then it should stay active during the reload or light back off shortly thereafter.

 

[SolarAndWood]

Both were DE cats, first was a 2140 and second was a 2190. Not sure of model years. The stove is our only source of heat so it is burned 24/7 7+ months. With small fires it was ok, but I could never figure out how to get consistent, reliable and safe burns without babysitting it. Watch carefully for any deterioration in the stove. It doesn't take much and the stove will go downhill fast if it isn't immediately taken care of.

What do mean by deterioration in the stove? Where is there deterioration and what do you do to take care of it?

How do you find your Blaze King in comparison? How long have you had it?

Any gasket or warping issues. I chose to not fix mine both times because of the price.

The Blaze King is full load every time, set the thermostat and forget about it. Big or small splits, locust or pine, does not matter. With maybe a half dozen exceptions, it has been burning non-stop since the day it arrived, 10/2/09.

 

[Gridlock]

Thanks much for the links. The you-tube video looks exactly like what is happening. This is one of the responses from the video that I might try:
"The problem is caused by depriving a hot fire of air too quickly. We have the exact same problem with our VC defiant. It helps to gradually turn down the air and then close damper. We leave the air valve open 1/3 overnight."

I'm also wondering if my CAT might be clogged a bit. I removed and vacuumed it, but did notice that I couldn't see light shining through a good portion of the honeycomb, when I shined a flashlight through. Does this seem like this could be causing or exacerbating the problem? It's interesting that I believe the CAT is not lighting off as easily as it did a couple of months ago.

That could be a big part of the problem right there. It should be cleaned regularly, approximately after each cord of wood burned.

I have cleaned it regularly (I just got this stove in January and have already cleaned it twice). I just used a vacuum to suck out any ash; I did not use pipe cleaners, water, or anything else.

 

[Gridlock]

You are experiencing classic backpuffing explosions caused by excessive combustion gases suddenly igniting. Not enough primary air to completely burn off the gases, so your cat is working overtime to burn them. I'm not familiar with the VC cat internal air flow, but in the old non-cat designs, secondary air comes into the secondary combustion chamber in cycles that are dependent on how much smoke is in the chamber. If the wood is producing lots of smoke, this pre-heated air can cause the gases to explode and you will get an alarming backpuff that comes right out of the secondary air intake hole. I stopped peaking into the hole after I caught one of those right in the eye. Luckily, I wear eyeglasses.

As far as your wood goes, don't let the easy ignition and good heat it it producing fool you. Partially seasoned oak will ignite fine since it is very dry on the outside. And despite the old wife's tale that you get poor heat from less than ideal wood, there is only a very small relative loss in sensible heat production from wood that is higher in moisture content. Over the range of moisture content that wood will actually burn, the total potential loss is, at the most, only 10-15% - not something you'd notice until you inventory your wood supply at the end of the burn season. Despite that fact, it will not burn as clean as drier wood and will make more smoke. In the non-cat design, you simply give it more air to burn it off as it is being formed. In a cat stove, the design calls for the smoke to be burned higher up in the box, outside of the primary burn zone. Too much smoke will not be adequately addressed by the cat alone and it will build up in the box. This is why you need very dry wood for a cat stove.

Yes, get a moisture meter. I checked the cheap HF meter (<$12) against the completely accurate oven-dry testing method and found that it was close enough for firewood. Check the outside of several pieces, then split them in half and measure the inside surface. Total MC will be close to the average of these two readings. Between 18-20% is considered to be ideal. Even without a meter, you can just re-split the wood and hold it against your cheek. If it is not dry enough inside, it will feel cool and moist.

Unless your neighbor happens to be Quads, chances are he hasn't seasoned that oak for the three years necessary to get it down to 20%.

Thanks for the detailed explanation. I will get a moisture meter and check to see what I'm dealing with. This past season I got my wood very late, actually in the end of the Fall, so if it wasn't seasoned well to begin with, it certainly had no time to dry out after it was delivered. I am getting my wood soon, so at least it will have a chance to dry throughout thought the warm season; I do have a very good storage location which is completely protected from rain and snow, but gets a lot of airflow, so hopefully that will help the situation.

Do hardware stores like Lowes and Home Depot typically carry moisture meters?

 

[oldspark]

Can you get some dry wood from some one to try out quick? It does seem strange to me that the guide lines for dry wood do not apply to Oak (starting slow, sizzleing) I have been burning Oak for 30 years and think it is great wood, some times dry oak does not even start well if too small a fire, are you sure it is oak you are dealing with?

 

[Gridlock]

Can you get some dry wood from some one to try out quick? It does seem strange to me that the guide lines for dry wood do not apply to Oak (starting slow, sizzleing) I have been burning Oak for 30 years and think it is great wood, some times dry oak does not even start well if too small a fire, are you sure it is oak you are dealing with?

I can possibly get some wood from the chimney sweep, but I don't know anyone else who burns wood for heat.

I was told by my neighbor who delivered the wood that it is mostly oak, but I'm don't know enough about it myself to be able to tell. I can usually tell the wood type of a piece of furniture, but don't know how to tell from a split.

 

[schortie]

We had the same problem with our Defiant NC. I was convinced it must be the wood, turning the air down too soon, warm temps etc. It turns out that our stove would backpuff when it felt like it. Dry wood, cold weather, air open, air closed, it didn't matter. I became very tired of stressing over what could have been causing it to burp smoke all over the house.

The only way for us to truly fix the problem was to get a new stove - and we did. If you check it out on these forums, most of the folks with consistent backpuffing problems are using a VC stove. I'm sorry that this doesn't help your cause, but hopefully it will save you some stress.

 

[oldspark]

We had the same problem with our Defiant NC. I was convinced it must be the wood, turning the air down too soon, warm temps etc. It turns out that our stove would backpuff when it felt like it. Dry wood, cold weather, air open, air closed, it didn't matter. I became very tired of stressing over what could have been causing it to burp smoke all over the house.

The only way for us to truly fix the problem was to get a new stove - and we did. If you check it out on these forums, most of the folks with consistent backpuffing problems are using a VC stove. I'm sorry that this doesn't help your cause, but hopefully it will save you some stress.

So you are saying the only wat to fix it is to jack up the stove pipe and put a new stove under it? Sorry I dont mean to make fun of your situation as problems like this suck!

 

[Gridlock]

So you are saying the only wat to fix it is to jack up the stove pipe and put a new stove under it? Sorry I dont mean to make fun of your situation as problems like this suck!

Even if I do consider another stove, there are very few that I like aesthetically, are large enough for the space, and are CAT models. Although I am not 100% wedded to CAT stoves, I do really like how they work, and when things are working well how long of a burn I'm getting. The VC Defiant certainly does look pretty. Another CAT stove that I might be interested in is the new large Woodstock model coming soon, although I think I still prefer the look of cast iron over soapstone.

 

[Gridlock]

We had the same problem with our Defiant NC. I was convinced it must be the wood, turning the air down too soon, warm temps etc. It turns out that our stove would backpuff when it felt like it. Dry wood, cold weather, air open, air closed, it didn't matter. I became very tired of stressing over what could have been causing it to burp smoke all over the house.

The only way for us to truly fix the problem was to get a new stove - and we did. If you check it out on these forums, most of the folks with consistent backpuffing problems are using a VC stove. I'm sorry that this doesn't help your cause, but hopefully it will save you some stress.

From what I've read though, the VC CAT and Everburn models are completely different animals. I do wonder how many others have similar issues with the CAT models and how that compares to other brands of CAT stoves. Which stove did you end up replacing it with?

 

[Wood Heat Stoves]

I tried a while searching for ‘hidden’ phone numbers on the internet for VC, but with no luck. How can a company like this have no contact information?

if you still want a contact #...
Customer Svc. # - 800-525-1898

 

[Todd]

Sounds like you may be turning down the air to quickly causing a quick build up of gases. Try adjusting the air down further in the bypass mode so the stove pressures equalize then engage the cat.

Well, this time I kept the air control at maximum until the stovetop temp was 600-650 degrees. If I kept it at that setting much longer, I would have been seeing temps over 700.

I've tried both lowering the air control quickly, and waiting for a while, but can so far not seem to get consistency.

Sorry, that didn't come out right. Once you hit that 500 mark in the reloading bypass mode cut the air down to 1/4 and let her settle down for a few minutes, then engage the cat. Have some patients the flames may die or become slow and lazy which is normal. It wil take some trial and error finding the right air settings.

 

[Gridlock]

I tried a while searching for ‘hidden’ phone numbers on the internet for VC, but with no luck. How can a company like this have no contact information?

if you still want a contact #...
Customer Svc. # - 800-525-1898

Thanks much; I actually did call that number which is for Monessen, not Vermont Castings. You still can't speak to someone; according to the voice mail, you can leave a message and possibly get a call back within 5 days. They obvsiosly don't want to speak to idividual consumers; they mention on the message that consumers should talk to their dealer.

Very crappy customer service if you ask me.

 

[Gridlock]

Sorry, that didn't come out right. Once you hit that 500 mark in the reloading bypass mode cut the air down to 1/4 and let her settle down for a few minutes, then engage the cat. Have some patients the flames may die or become slow and lazy which is normal. It wil take some trial and error finding the right air settings.

Ah, I see, thanks. That does seem to be the consensus, but I thought the CAT wasn't lighting up well when I tried that since the temperature dropped quite a bit, but I'll have to try it again.

 

[grommal]

Earlier this year, on the advice of my chimney sweep, I replaced an Avalon Olympic insert with a Vermont Castings Defiant Catalytic free standing stove. The Defiant does produce a huge amount of heat, but like a spoiled child, is extremely difficult to control. This is what happened tonight, which is typical:

I started it from a cold start around 8:00pm; as usual it starts and gets going very easily. By 8:30, the top griddle temperature is about 650-700 degrees. I lower the air control and let it burn for another 30 minutes until I have a nice bed of coals; so far so good.

I then add a few splits filling the firebox about half way, let it burn for about 10 minutes, then close the damper, engaging the CAT. I turn on the Condor digital CAT gauge to monitor CAT chamber temperature. Within about 15 minutes, the CAT chamber temperature climbs from 500 to about 1300. I then lower the air control to a little more than half open. After about 10 minutes, things start to go south.

I start noticing sudden explosions in the firebox, which causes smoke to force it's way out the top loading door. The CAT chamber is reading 1700 degrees, and the stove top 600. The whole house smells like smoke. I open the air control more which after about 10 minutes, allows more flame in the firebox which helps the smoke get burned, but also increases the stove top temperature to over 700 degrees. Finally after much fiddling, both the CAT and stove top temperature drop a bit, and it runs Ok.

At other times, I've seen CAT chamber temps over 2100 degrees, and the only way to cool it down is to open the damper for a while. Although I'm not completely sure, I don't believe the wood is the problem since it starts and burns very easily and I don't hear any sizzle or see any bubbling.

What is going on here? The stove produces great heat, but is so difficult to control. Is this typical with EPA or CAT stoves, or is the Defiant just not a well designed stove?

I just paid a lot of money on this stove, but am getting so frustrated that am thinking about a replacement, maybe the new large Woodstock stove when it comes out. The other issue is that there doesn't seem to be any way to contact Vermont Castings; I tried a while searching for 'hidden' phone numbers on the internet for VC, but with no luck. How can a company like this have no contact information?

Identical issue I had with my old VC cat stove. Never could figure out how to make it behave itself reliably.

Hope you have better luck than I did.

 

[Gridlock]

Identical issue I had with my old VC cat stove. Never could figure out how to make it behave itself reliably.

Hope you have better luck than I did.

Are you having better luck with your new stove? The Jotul is a non-cat stove, correct? Can you get the kind of heat and burn times with the Jotul as you did with the VC? Did you choose a non-cat stove intentionally due to the difficulty you had with the VC CAT?

Sorry for all the questions, but if I were to get a non-cat stove as a replacement for my current stove, the Jotuls would be high on the list because I prefer the cast iron look, and Jotul does seem to have a pretty good reputation.

 

[grommal]

Identical issue I had with my old VC cat stove. Never could figure out how to make it behave itself reliably.

Hope you have better luck than I did.

Are you having better luck with your new stove? The Jotul is a non-cat stove, correct? Can you get the kind of heat and burn times with the Jotul as you did with the VC? Did you choose a non-cat stove intentionally due to the difficulty you had with the VC CAT?

Sorry for all the questions, but if I were to get a non-cat stove as a replacement for my current stove, the Jotuls would be high on the list because I prefer the cast iron look, and Jotul does seem to have a pretty good reputation.

I don't think it's a cat vs. non-cat issue. I think it's a VC design issue. Other cat stoves like Woodstock or BK would probably be fine.

Just so you know, we tried everything everybody suggested. Super dry wood made no difference. Backing down on the primary air very slowly made no difference. Turning the air down first and then closing the bypass made no difference. Rebuilding the stove with all new gaskets and new refractory chamber in the back made no difference. Cleaning the combustor, or putting a new one in, or removing it altogether made no difference. I'm convinced that we had a particular combination of chimney behavior and stove design that just could not be made to work.

Yes, the new Oslo is non-cat. But regardless of that, it solved our backpuffing problem entirely. We made zero modifications to the chimney, and changed only the stove. My wife just loves it. It is so easy to run and so stable compared to the cantankerous old stove that I think my wife would marry it if she weren't already taken. Then again, if I were as stable and easy to run as the Oslo, maybe she wouldn't be tempted!

 

[Gridlock]

I don't think it's a cat vs. non-cat issue. I think it's a VC design issue. Other cat stoves like Woodstock or BK would probably be fine.

Just so you know, we tried everything everybody suggested. Super dry wood made no difference. Backing down on the primary air very slowly made no difference. Turning the air down first and then closing the bypass made no difference. Rebuilding the stove with all new gaskets and new refractory chamber in the back made no difference. Cleaning the combustor, or putting a new one in, or removing it altogether made no difference. I'm convinced that we had a particular combination of chimney behavior and stove design that just could not be made to work.

Yes, the new Oslo is non-cat. But regardless of that, it solved our backpuffing problem entirely. We made zero modifications to the chimney, and changed only the stove. My wife just loves it. It is so easy to run and so stable compared to the cantankerous old stove that I think my wife would marry it if she weren't already taken. Then again, if I were as stable and easy to run as the Oslo, maybe she wouldn't be tempted!

Thanks for the info. Do you find that the Oslo produces as much heat and burns as long as the VC? I'm asking because when the VC is working properly, it produces a lot of heat and long burn times, much more so than my older non-cat stove. I realize it's not an apples-to-apples comparison since the older stove was an insert and the VC is freestanding in front of the fireplace, but the VC still seems to produce more heat and burns much longer. I have read a lot about CAT vs non-CAT, and wondering in your experience if the Oslo does as good a job as the VC CAT did. In VC's literature, they state the their CAT model is better as a primary heat source due to it's higher effeciency.

 

[grommal]

I don't think it's a cat vs. non-cat issue. I think it's a VC design issue. Other cat stoves like Woodstock or BK would probably be fine.

Just so you know, we tried everything everybody suggested. Super dry wood made no difference. Backing down on the primary air very slowly made no difference. Turning the air down first and then closing the bypass made no difference. Rebuilding the stove with all new gaskets and new refractory chamber in the back made no difference. Cleaning the combustor, or putting a new one in, or removing it altogether made no difference. I'm convinced that we had a particular combination of chimney behavior and stove design that just could not be made to work.

Yes, the new Oslo is non-cat. But regardless of that, it solved our backpuffing problem entirely. We made zero modifications to the chimney, and changed only the stove. My wife just loves it. It is so easy to run and so stable compared to the cantankerous old stove that I think my wife would marry it if she weren't already taken. Then again, if I were as stable and easy to run as the Oslo, maybe she wouldn't be tempted!

Thanks for the info. Do you find that the Oslo produces as much heat and burns as long as the VC? I'm asking because when the VC is working properly, it produces a lot of heat and long burn times, much more so than my older non-cat stove. I realize it's not an apples-to-apples comparison since the older stove was an insert and the VC is freestanding in front of the fireplace, but the VC still seems to produce more heat and burns much longer. I have read a lot about CAT vs non-CAT, and wondering in your experience if the Oslo does as good a job as the VC CAT did. In VC's literature, they state the their CAT model is better as a primary heat source due to it's higher effeciency.

It is our primary heat source. We think it produces a bit more heat than the VC did, and also goes for a bit longer on a load of wood. This is attributable to its somewhat larger firebox volume. After 8 or 10 hours at night, I always had a very robust bed of coals that I could just toss the next load onto. With the VC, we also always had coals in the morning, but a smaller layer with less heat to fire up the next load.

The only complaint I'd have is a minor one for us. There is a design issue that causes some ash to become trapped in a pocket of space at the bottom of the front door. When the door is opened, that ash dumps out onto the ash lip. This would probably bother us more if we used the front door routinely. The Oslo is also a side loader, and the side door does not have the same issue. Because of the airflow pattern inside the stove and around the baffle, side loading also minimizes the chance of getting even a tiny bit of smoke in the house during reloading. Since there's no bypass to open, the smoke must travel to the front of the stove in order to rise past the baffle, and if you're not careful you can get some smoke escape from the front if the draft isn't super strong. You can be pretty sloppy with the side door procedure, basically just yanking it open, without getting a lot of smoke. If you open it carefully, no smoke at all escapes.

We've only had it for a year now, but I'd buy the Oslo again in a heartbeat. The only thing I'd change is that I'd spring for the extra $$ to get the super-attractive blue-black enamel, rather than the flat black painted finish that we chose.

 

[Gridlock]

It is our primary heat source. We think it produces a bit more heat than the VC did, and also goes for a bit longer on a load of wood. This is attributable to its somewhat larger firebox volume. After 8 or 10 hours at night, I always had a very robust bed of coals that I could just toss the next load onto. With the VC, we also always had coals in the morning, but a smaller layer with less heat to fire up the next load.

The only complaint I'd have is a minor one for us. There is a design issue that causes some ash to become trapped in a pocket of space at the bottom of the front door. When the door is opened, that ash dumps out onto the ash lip. This would probably bother us more if we used the front door routinely. The Oslo is also a side loader, and the side door does not have the same issue. Because of the airflow pattern inside the stove and around the baffle, side loading also minimizes the chance of getting even a tiny bit of smoke in the house during reloading. Since there's no bypass to open, the smoke must travel to the front of the stove in order to rise past the baffle, and if you're not careful you can get some smoke escape from the front if the draft isn't super strong. You can be pretty sloppy with the side door procedure, basically just yanking it open, without getting a lot of smoke. If you open it carefully, no smoke at all escapes.

We've only had it for a year now, but I'd buy the Oslo again in a heartbeat. The only thing I'd change is that I'd spring for the extra $$ to get the super-attractive blue-black enamel, rather than the flat black painted finish that we chose.

Thanks for the info. I would have thought that the VC produced longer burn times due to the CAT.

One more question: do you find you need to babysit the Oslo; can you get it up to temperature, load up the firebox, and feel confortable that it will burn properly without back-puffing, over-firing, etc? Can you load it and leave for the day feeling confortable that your house won't be a pile of ashes when you get back?

 

[SolarAndWood]

It is our primary heat source. We think it produces a bit more heat than the VC did, and also goes for a bit longer on a load of wood. This is attributable to its somewhat larger firebox volume. After 8 or 10 hours at night, I always had a very robust bed of coals that I could just toss the next load onto. With the VC, we also always had coals in the morning, but a smaller layer with less heat to fire up the next load.

Thanks for the info. I would have thought that the VC produced longer burn times due to the CAT.

The cat doesn't buy you anything for burn time when its cold out and you are burning at a higher rate similar to what you would burn in the non-cat anyway. At that point, it is just firebox size.

 

[jharkin]

I just finished the fist winter with an old VC Encore cat and I had similar problems to you. I partially resolved it by sorting the wood and burning only the driest stuff... but also I found that letting it burn with the bypass open for a longer time after reload helps a lot. Instead of 10min I would leave it open 20-30 and let the stove get REALLY hot. Seems to make a big difference to get the whole load charred before that damper down and then slowly lower the air.

I think what happens is that if you just burn it for 10min then quickly shut the bypass and lower the air it quenches the flames too fast, creates a ton of smoldering and overwhelms the cat.

BTW, to test for bad wood go to the grocery store and buy a couple of those $5 wood bundles. that stuff is usually kiln-dried.

-Jeremy

 

[grommal]

It is our primary heat source. We think it produces a bit more heat than the VC did, and also goes for a bit longer on a load of wood. This is attributable to its somewhat larger firebox volume. After 8 or 10 hours at night, I always had a very robust bed of coals that I could just toss the next load onto. With the VC, we also always had coals in the morning, but a smaller layer with less heat to fire up the next load.

The only complaint I'd have is a minor one for us. There is a design issue that causes some ash to become trapped in a pocket of space at the bottom of the front door. When the door is opened, that ash dumps out onto the ash lip. This would probably bother us more if we used the front door routinely. The Oslo is also a side loader, and the side door does not have the same issue. Because of the airflow pattern inside the stove and around the baffle, side loading also minimizes the chance of getting even a tiny bit of smoke in the house during reloading. Since there's no bypass to open, the smoke must travel to the front of the stove in order to rise past the baffle, and if you're not careful you can get some smoke escape from the front if the draft isn't super strong. You can be pretty sloppy with the side door procedure, basically just yanking it open, without getting a lot of smoke. If you open it carefully, no smoke at all escapes.

We've only had it for a year now, but I'd buy the Oslo again in a heartbeat. The only thing I'd change is that I'd spring for the extra $$ to get the super-attractive blue-black enamel, rather than the flat black painted finish that we chose.

Thanks for the info. I would have thought that the VC produced longer burn times due to the CAT.

One more question: do you find you need to babysit the Oslo; can you get it up to temperature, load up the firebox, and feel confortable that it will burn properly without back-puffing, over-firing, etc? Can you load it and leave for the day feeling confortable that your house won't be a pile of ashes when you get back?

One more point of clarification on heat output and firebox size. Our old VC was called a Defiant Encore, 1986 vintage. I think they later changed the name of that model to just Encore to reduce confusion with the Defiant, which was a larger stove, at least in 1986. I don't know how they compare to the Defiant you have, as I didn't keep up with VC models over the years.

On the babysitting question, in our installation the Oslo runs with minimal attention. We get good startup with the doors all closed (though some folks here report having to leave a door cracked open for a little while). Once up to temperature, I've found that I can throttle it back pretty much all at once to the desired setting, and forget it until the next reload. After a full year of use (end of the season last year through end of the season this year), we had zero problems with overfire, underfire (smoldering), backpuffing, etc. Not a single instance of any problems at all. In the mornings I find a nice bed of coals that I can just toss another full load of wood onto, wait a couple of minutes to establish the burn, and throttle it back and forget it for another 8 hours or more.

The key to good behavior with the stove is to avoid excessive raking of the coals. You want a good layer of ash on the stove bottom. I rake only a tiny bit, and not on every reload. Doing it this way allows the ash pan to go for a week without emptying, but in the beginning I was emptying it every couple of days and sneaking up on the week-long interval.

As many others have noted in many other discussions here, dry wood is key. Really dry wood. It's like night and day. With DRY wood, secondary combustion lasts for hours, and you get much more heat out of a load (probably a combination of max secondary combustion plus not wasting BTUs boiling excessive water to steam). If the wood is kinda sorta dry, you get secondaries for less time, and get less heat.