The Age Old Question... Catalytic vs Secondary Stove

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BurnIt13

Minister of Fire
Jun 10, 2010
636
Central MA
About 12 years ago the answer to this question seemed to a bit different than it is today, so now that I'm back in the market I figured I would ask it again.

When set to "low and slow" do the newer catalytic stoves produce much creosote and soot in the flue? My old house is well insulated now and a low and slow burn would suit us best. With my older secondary burner stove I always paid attention to the flue temps rather that the stove temps. I always tried to keep the flue temps between 500-700F for a clean burn and minimal soot/creosote build up. My flue has always been squeeky clean.

That said...what are typical flue temps of Catalytic stoves when set to low... but not too low as to produce smoke?
 
Since 12 yrs ago, the 2020 EPA regs kicked in. This brought about several new hybrid stoves to complement the few that were already on the market. They tend to burn with a bit hotter flue gases than some of the low and slow full catalytic stoves. More like in the 300-400º range. That said, if the wood is dry, the stove is run properly, and the flue system is well-insulated and interior, then creosote buildup should not be excessive. Ask this question in the BlazeKing and Woodstock forums for specifics and look up past threads on this topic there.

The other big change since 2011 is stove prices. They have gone up a lot since then, especially in the past year. There is a 30% tax credit (if you can take it) that caps out at $2,000 on several of these cat and cat hybrid stoves, though you won't see the credit until submitting taxes next year.
 
I was cash poor with a baby on the way back in 2011 when I got my Englander. Uninsulated house with steam heat and $750 monthly heating bills. I got the Englander for $600 on a tax free holiday and a 10% coupon after Home Depot reduced the price in the spring. It did its job!

My flue is 22' with about 10' of it exiting the roof. I do not want to deal with creosote, though who would. With my Englander, keeping the flue temps at about 500-600 with good wood... I get about a cup of dry sooty powder every year. And that was with about two cords of wood.

The lower flue temps, sometimes less than ideal wood and half of my flue being external makes me hesitant on the Hybrids and Full Catalytic stoves.
 
You can keep a cat stove or hybrid at that flue temp too, along with higher stove temps and less advantage for the complexities of the cat stove.
 
I don’t think cat or hybrid stoves run that much lower flue temps than a good non cat. Maybe a Blaze King does. I have the same height chimney as you and my non cat runs 400-600 internal pipe temps with very little creosote, maybe a quart of fine powder.
 
Pure cat stoves (BK, Kuma, some Buck and Woodstock) will have a lower flue temp, when run low and slow. The cat is able to burn smoke at a lower ignition temperature (>500ºF) than a non-cat's secondary burn temp (1100ºF). It's not uncommon for a cat stove's flue gas temp to be in the 250-350º range when burning low and slow.
 
I don’t remember any of my previous cat stoves running quite that low flue temps but they were less prone to runaways than non cats.
 
There are lots of variables with stove installs and the heat demand placed on the stove.
 
OP...you pointed out the correct & most important wording....quality, well seasoned firewood is the most important factor.

As for complexities of running a catalytic stove (correctly), my 11 year granddaughter has done it since she was 8 years old. Once she was shown the correct procedure, it became simplistic.

Your chimney height seems ideal for any wood stove and your burning practices appear solid.

Choose the best one for your home and as BeGreen pointed out, the 25C Tax credit may help!

BKVP
 
As an owner of both an Englander nc30 and a fancy cat stove I can tell you that creosote will occur with both. No real change there. Low and slow in your home keeping it warm is much better than the pulse and glide of your noncat Englander. Yes, the cat stoves are more complicated to start up but after startup you don’t touch it for the rest of the very long burn cycle so it’s easier to run.

It may have been a decade since you last looked but nobody but BK has the functional thermostat and the proven ability to run at such low outputs.
 
I can’t speak to flue temps because I don’t measure them. I can share my experience, which my differ drastically from yours. We live in a small, poorly insulated log home in western Colorado. We have long cold winters. We burn Aspen, lodgepole, and Douglas fir, all well seasoned. We had an Avalon tube stove for 25 years, and I would clean large amounts of creosote out of the chimney three times each winter. This is a 6”, single wall inside, double wall outside, straight, approximately 14’ chimney. By large amounts I mean a quart or two per cleaning.

Last year we installed a Kuma Wood Classic, and all double wall pipe. Over our 7 month burning period, I “cleaned” the chimney twice. Each time I got about 3 tablespoons of soot/creosote out. The Kuma is a hybrid stove, not pure cat. Running it properly is simple. We can’t always run it on low because when it’s -25 outside this house won’t stay warm without a little more than low. However, we did run on low much of the time. The difference was astounding. Again, just my experience.
 
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The Kuma is a good stove and new stoves are definitely cleaner, but the double-wall stove pipe inside is also helping keep the flue gases hotter and keeping the creosote level down.
 
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Thank you all! BK stoves have always been intriguing to me but due to my clearance/size requirements the only one that would really fit is the newish Boxer 24.1 because it can be installed with as little as 2.75" of corner clearance.

But to be honest I think the best option for me is a Hybrid type stove, or a quality secondary stove. With clearances and appearance considered...here is my list of contenders:

Hybrid Stoves:
- Hearthstone Green Mountain 40
- Hearthstone Craftsbury
- Kuma Aspen LE

Secondary Stoves:
- Pacific Energy Vista Classic LE
- Pacific Energy Super Classic LE
- Drolet Escape 1500
 
Thank you all! BK stoves have always been intriguing to me but due to my clearance/size requirements the only one that would really fit is the newish Boxer 24.1 because it can be installed with as little as 2.75" of corner clearance.

But to be honest I think the best option for me is a Hybrid type stove, or a quality secondary stove. With clearances and appearance considered...here is my list of contenders:

Hybrid Stoves:
- Hearthstone Green Mountain 40
- Hearthstone Craftsbury
- Kuma Aspen LE

Secondary Stoves:
- Pacific Energy Vista Classic LE
- Pacific Energy Super Classic LE
- Drolet Escape 1500
I don’t put the Drolet in the same category as the others. It’s a great budget stove but definitely not a direct comparison to the PE stoves. I do question why you wan the 1500 and not the 1800? (I have the 1800).
 
@EbS-P Clearances. For the new hearth pad I plan to construct the 1800 would only be 14" from the door opening to the edge of the tile hearth. The 1500 would be 19". I am going to be making a tile hearth flush with the existing wood floor.

The PE Vista Classic and Super Classic would be 22.5" and 19".
 
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Super or the Aspen LE.
 
@begreen If I recall the PE Super is a N/S loader, can you confirm? Based on the pictures it looks like the Kuma Aspen LE is too. That's a big plus if that is the case.
 
Yes, it is. I agree, N/S is my preferred way to load. The True North TN20 is the value version by PE. Also a N/S loader.