All great input and mostly accurate. Catalytic wood stoves earned a terrible (and deserved) reputation in the 1980's into the early 1990's. In 1984 Oregon became the first state to regulate wood heaters. The Feds began in 1988. So if you were one of the 1,200 or more stove manufacturers in the world selling wood stoves, you knew Oregon was a big part of the sales market. 99% of the wood stove manufacturers shoved cats into their stoves so they could sell them in Oregon. It was a magic pill! Unfortunately it was not understood what the effects of wood combustion would have on the combustors. Consumers were told they overfired their stoves. Dealers were told they did not educate the consumers correctly and the truth is....manufacturers rushed product to market without understanding the consequences. This is the risk of poorly timed regulatory impact.
Most manufacturers stopped making combustor equipped stoves and instead designed stoves that burned cleanly by thermal destruction. And of course they began bad-mouthing catalytic designed stoves. Much like you won't find the Ford sales guy boasting about Chev. trucks! We and a few other continued with chemical conversion. We began to figure out the ills of solid fuel combustion and the toll it takes on combustors. One coal stove manufacturer tried to add a combustor and called us...we said it won't work because the sulfur will poison the combustor. Well, they ditched that effort thankfully.
The truth is you must figure out a way to limit the upper temperature of the combustor. Most if not all the original combustor equipped stoves had combustor peak temperatures of around 1,800-2,000F. The fact is that when the combustor hits 1600F or higher repeatedly, the wash coat, which carries the precious metals flattens out and looses surface area. Eventually this means the combustor is no longer able to do the intended job. Just as is the case when secondary air tubes or baffles warp or distort or even crack. You see you might not notice such failure (which is costly to replace) but if your stove has a combustor you can see the failure in both terms of performance and if a ceramic substrate is used ceramic, a pile of debris in your wood stove.
So how does a combustor hit such excessive temperatures, one possibility is poor design. But in 99% of the cases that is not the cause. It's stack effect, the difference between outside and inside temps creates this effect. So if it's 70 in your home and 50 outside, the differential of 20 degrees wont create much stack effect. But if it's 70 inside and 0 or even lower outside, the stack effect increases dramatically. If the stove does not embody in the design a way to regulate the amount of air pulled into the stove by the chimney (stack effect), you can easily over fire a stove. In a combustor equipped stove, that can lead to flattening of the wash coat. In a secondary combustion stove, it can lead to excessive temps for the essential elements needed for continued clean burning. In the end, regardless of technology, we must all be responsible stove owners and conduct annual inspections....and when needed parts replacement. We have a thermostat that prevents such excessive combustor temperatures.
Do combustors wear out? Yes! Just like the tires on your truck, they wear out slowly over time if the stove is properly designed. And candidly all surface materials subjected to excessive temperatures will fail at some point, not just combustors. Acknowledging the need to replace the combustor, you have to figure that into your purchasing decision. Just be wise enough to know that just because a steel parts hasn't fallen into the coals doesn't mean it is a new as the day you lit the first match. Dealers will often remark that when they are given the opportunity or asked to inspect a wood heater, they can and do find lots of things others might think are not an issue.
And no one should burn green wood. In ANY stove design, burning green wood is why regulators have placed bullseye's on wood heating! Moisture in the fuel load is the single greatest contributor to excess particulates (smoke). You know you are a responsible wood burner when you drive down the street or country road and see smoke pouring out of a stack and care...... that is what gives us all a black eye. Also, creosote cannot form into that crusty crap unless there is some form of combustion moisture, so don't burn green wood. Instead, get 2-3 years ahead on your wood needs and split and stack under cover.
Regardless of technology used, all wood stoves require regular inspections and maintenance. Also, remember that on January 1, 2021, the outgoing administration signed into law at 26% Federal Tax credit for wood and pellet stoves that have efficiencies greater than 75 HHV. Keep in mind this list of eligible wood heaters may increase as more units come to market. The 26% applies to the chimney, labor to install, hearth pad etc. So you just don't save 26% on the stoves, it extends across all of the above and that folks is one heck of a lot of money. There is no limit to the credit as well, as there was in previous credits.
This pdf is as of today. You will have to print it out and paste side by side to see the full details.
Thank you all, stay well and warm!
BKVP
Not in the real world. I was heating 1400 sq.ft. I assumed at the time, 2004 maybe, the technology wasn't there to make a larger stove with a converter in it. I am not sure how far the tech has come, but I assume it has advanced and you can get a larger box with a combuster. I have since replaced that stove with an All Nighter(similar to Fisher Moma Bear, Poppa Bear, etc. Probably made by the same co?) Huge firebox. Conventional burner. Keeps a fire forever!
Prolly 16 hours. Just cleaned my chimney the other day. It was a chore. It was all I could do to get the brush through on the first pass. Just my 2 cents. I would go back to a catalitic stove in a heartbeat if I was sure it would keep a fire for 16 hours, and get a better burn on the coals. They ain't cheap! Phew...... That was a lot for dated opinion!
