Cat stove questions

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ditchrider

Burning Hunk
Dec 6, 2011
190
North central, CO
I bought my stove already, and am happy with it. But in discussions and debates I still have questions that I just want answers to. The big one is the efficiency of a stove with a catalytic converter versus a stove with an air manifold/reburner. The leading opinion is often that a cat stove gives a longer burn and therefore is more efficient. I guess I just assumed the stove companies and the EPA tested wood with a known BTU content and measured the BTU's actually produced by the stove/fireplace. Thus BTU's produced divided by the BTU potential of the wood determines the efficiency, right? If this discussion has already taken place please just point me to the post/discussion.

Also, do certain species of wood burn at better/worse efficiencies in a cat stove versus a reburner type stove? For example.. will cottonwood be more efficiently burned in a cat stove while ash will provide more efficiency from a reburner or vice-versa? I didn't come by that question from any other perspective than just trying to grab examples out of the air and try to apply them.
Thanks for any input
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
ditchrider said:
I bought my stove already, and am happy with it. But in discussions and debates I still have questions that I just want answers to. The big one is the efficiency of a stove with a catalytic converter versus a stove with an air manifold/reburner. The leading opinion is often that a cat stove gives a longer burn and therefore is more efficient.

Cat stoves are a little more efficient in certain aspects. The main thing is that a cat stove allows you to burn at a lower temperature in a cleaner manner. Due to the fact that you can maintain a lower temperature burn the stove is able to burn longer. Also, not all cat stove are created equal. There is a big difference from, say, a Vermont Castings catalytic stove to a Blaze King catalytic stove.

I guess I just assumed the stove companies and the EPA tested wood with a known BTU content and measured the BTU's actually produced by the stove/fireplace. Thus BTU's produced divided by the BTU potential of the wood determines the efficiency, right? If this discussion has already taken place please just point me to the post/discussion.

BTU rating you see listed on the stove are inconsistent and unreliable. It is best to focus on the size of the firebox when comparing stoves. And yes, the discussion of catalytic stoves vs. non-cat stoves is brought up quite often.

Also, do certain species of wood burn at better/worse efficiencies in a cat stove versus a reburner type stove? For example.. will cottonwood be more efficiently burned in a cat stove while ash will provide more efficiency from a reburner or vice-versa? I didn't come by that question from any other perspective than just trying to grab examples out of the air and try to apply them.
Thanks for any input

A dense, hardwood will produce more BTUs than a softwood. This means they offer more BTUs and longer burn times no matter which type of stove they are being burned in.

In short, cat stoves are a little more efficient. Cat stoves offer greater control over the temperature. This allows for longer burn times. If your stove is over-sized for your area, it would be more noticeable that the wood consumption has decreased when comparing cat vs non-cat since you would be able to burn at a lower temp and extend the burn times.

Is one technology better than the other? For the most part, no if both are burned correctly.

If you find you need to burn your stove at its upper limits to heat your whole house than you will not notice much difference if you took that same stove and made it a catalytic stove. Burn times might increase a bit but it would not be a game changer.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
I ran a cat stove for close to 25 yrs. and now have a secondary burn stove and these are my observations.. A cat stove can be run at much lower temps than a secondary burn stove and does that cleanly. Cat stoves run best in low to medium situations and my stove best at low,, Secondary burn stoves heat up faster tend to be peaky and run well in pretty much all temps.. I find a blower helps even out the spikes but then again this a convection stove and so was my cat stove.. I find both stoves to be very efficient and much to my surprise they long burns seem to be a bit longer with my secondary burn stove but I think the firebox is slightly larger.. I do not equate long burn times with efficiency I feel it's a matter of how much heat gets extracted from the wood and placed into the space to be heated vs. up the chimney.. In this regard both of these stoves perform admirably.. Cat stoves do burn the cleanest and with the high temps in a cat most everything is destroyed that passes through a hot cat however over time they do degrade especially if not cleaned periodically but that usually is a fast and easy thing to do..

Ray
 

ditchrider

Burning Hunk
Dec 6, 2011
190
North central, CO
Thank you for the inputs! I was a plant scientist for many years so I spent a lot of time disciphering statistics and data. I noticed stove ratings can be really different depending on who conducts the tests. I do understand that different wood species have varying heat potential and the harder and heavier a wood the better. But let's say if the majority of the wood I have available to burn is cottonwood. Since the heat potential is crappy to begin with, will you actually realize the efficiency of the cat stove because it does a better job of a clean burn at a lower temps? Or if I live near a mountain town where the majority of wood is pine and fir. The heat output of this is low also, but it produces a hot fire for a short period of time versus the low temp and longer burn of cottonwood. Will the reburner stove do just as well?

I have read a few reviews where the person just really insults one model of stove or another because it "just doesn't work". "But when I put my old stove back in.." or "When I returned it and switched to Brand B" all their problems were solved. Burning the same wood, stove located in the same place. Nothing different but the stove.
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
ditchrider said:
Thank you for the inputs! I was a plant scientist for many years so I spent a lot of time disciphering statistics and data. I noticed stove ratings can be really different depending on who conducts the tests. I do understand that different wood species have varying heat potential and the harder and heavier a wood the better. But let's say if the majority of the wood I have available to burn is cottonwood. Since the heat potential is crappy to begin with, will you actually realize the efficiency of the cat stove because it does a better job of a clean burn at a lower temps? Or if I live near a mountain town where the majority of wood is pine and fir. The heat output of this is low also, but it produces a hot fire for a short period of time versus the low temp and longer burn of cottonwood. Will the reburner stove do just as well?

For the most part, the only way you will notice a big difference between the Cat stove and Non-cat stove, when using the same wood, is if you are burning at a lower temperature with the Cat stove. If both stoves are the same size and burn at the same temp you will notice about the same burn times, for the most part, with a slight edge to the Cat stove.

There are a lot of members here that only use softwood, like pine, due to their location. BeGreen, a mod here, uses softwood and can get 10+ hour burns from his non-cat, 3 cu ft Pacific Energy T6. You would get about the same burn time burn time from a catalytic Vermont Castings Defiant if the stove was run at the same temps from start to finish.

There are exceptions to the rule, and some Cat stoves would provide a longer burn, but that goes back to my original point that 'all Cat stoves are not created equally.'


I have read a few reviews where the person just really insults one model of stove or another because it "just doesn't work". "But when I put my old stove back in.." or "When I returned it and switched to Brand B" all their problems were solved. Burning the same wood, stove located in the same place. Nothing different but the stove.

A lot of times it has to do with how dry the wood is. Every year around this time your see threads about people that used to have big old Pre-EPA stoves. The Pre-EPA stove allows you to more easily burn wet wood more easily. You'll see a lot of threads of "This stove is crap, it won't even get above XXX degrees.

The other thing is that a lot of stove buyers base their decision on claimed BTU output. With the Vigilant I run (30+ year old stove) it has a, claimed, 50,000 BTU output. But, the firebox is a little larger than 2.5 cu ft. The Heritage I own has a usable firebox that is just under 2 cu ft, but a claimed BTU output of 55,000 BTUs. People will look at the BTU output and assume it will put out the same or more heat. Not true. The Vigilant will put out more heat the the Heritage.
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,811
Michigan
Welcome to the forum ditchrider.

We are now into our 5th winter with the cat stove, which is our first. We could not be happier no matter what type of wood we've burned but because of the emerald ash borer, right now our main wood is ash. However, I'd burn any type of wood that were available. If I had only cottonwood, I'd still be happy. No, it will not hold a fire as long as ash or oak but one can still heat with it. The biggest key to burning any wood is the moisture content of the wood and giving most wood a year to dry after being split is the number one key to good burns and clean burns.

As to efficiencies, most of the new stoves are close. What the benefit is with these new stoves is that you get more heat from the wood you burn. In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too. So I really could care less what the efficiency is in this stove as I know it is a clean burning stove. We've cleaned our chimney exactly one time so far for about a cup full of soot and no creosote.
 

richg

Minister of Fire
Nov 20, 2005
888
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
richg said:
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.

Upgrading from a Quad 4300 to a Blazeking will not gain you much in the way of efficiency as the Quad 4300 is an epa stove.. What it will do for you is allow you to burn at a low level for a long period of time.. Don't expect to use 50% less wood with this move or you will be disappointed.. Why are you "upgrading" and what are you hoping it will do for you? Dennis is a smart woodburner and gives good advice however upgrading from an efficient stove to another efficient stove will not save you as much wood as you think.. My 2 cents..


From the Quadrafire site: 4300 MILLENNIUM 79.82% efficency steady state .. That's about as good as it gets with small variations of that number..

Ray
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
richg said:
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.


What Dennis is leaving out is that the previous stove he was running was a pre-EPA stove. Pre-EPA stoves are a LOT more inefficient than an EPA stove. You will NOT see your wood consumption cut in half going from a Non-cat stove to a Cat stove.
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
raybonz said:
richg said:
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.

Upgrading from a Quad 4300 to a Blazeking will not gain you much in the way of efficiency as the Quad 4300 is an epa stove.. What it will do for you is allow you to burn at a low level for a long period of time.. Don't expect to use 50% less wood with this move or you will be disappointed.. Why are you "upgrading" and what are you hoping it will do for you? Dennis is a smart woodburner and gives good advice however upgrading from an efficient stove to another efficient stove will not save you as much wood as you think.. My 2 cents..


From the Quadrafire site: 4300 MILLENNIUM 79.82% efficency steady state .. That's about as good as it gets with small variations of that number..

Ray


+1

The princess is a bit larger of a stove, 2.4 cu ft vs. 2.8 cu ft. You will probably notice a drop in wood, but it will be no where near 50%. The drop in wood consumption will come from being able to burn at lower temps more easily and efficiently during shoulder season.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
BrowningBAR said:
raybonz said:
richg said:
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.

Upgrading from a Quad 4300 to a Blazeking will not gain you much in the way of efficiency as the Quad 4300 is an epa stove.. What it will do for you is allow you to burn at a low level for a long period of time.. Don't expect to use 50% less wood with this move or you will be disappointed.. Why are you "upgrading" and what are you hoping it will do for you? Dennis is a smart woodburner and gives good advice however upgrading from an efficient stove to another efficient stove will not save you as much wood as you think.. My 2 cents..


From the Quadrafire site: 4300 MILLENNIUM 79.82% efficency steady state .. That's about as good as it gets with small variations of that number..

Ray

+2 This is exactly what I was thinking.. The Quad 4300 looks like a nice stove and should work great in a really, really, really old farmhouse if the selling price is right :)

Ray


+1

The princess is a bit larger of a stove, 2.4 cu ft vs. 2.8 cu ft. You will probably notice a drop in wood, but it will be no where near 50%. The drop in wood consumption will come from being able to burn at lower temps more easily and efficiently during shoulder season.
 

richg

Minister of Fire
Nov 20, 2005
888
BrowningBAR said:
richg said:
Backwoods Savage said:
In our case, we've cut our fuel needs in half with the cat stove and stay a whole lot warmer in the house too.

Dennis,

Coming from an experienced wood burner like you, this is a very telling statement. When the cash situation permits, I will be ordering a Blaze King Princess to replace my Quad 4300.


What Dennis is leaving out is that the previous stove he was running was a pre-EPA stove. Pre-EPA stoves are a LOT more inefficient than an EPA stove. You will NOT see your wood consumption cut in half going from a Non-cat stove to a Cat stove.

Having had a Fisher Grandma Bear, now things are in context.
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,811
Michigan
Definitely one will not experience a big gain if trading an epa stove for another. It is in the upgrading from the old smoke dragons to the new epa stoves that will get the gain. Most tend to report using about 1/3 less wood rather than our 1/2. Nonetheless, using only half the wood we used to is super sweet. Sorry if I mislead anyone as I perhaps should have stated what our old stove was and it was an Ashley.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
Backwoods Savage said:
Definitely one will not experience a big gain if trading an epa stove for another. It is in the upgrading from the old smoke dragons to the new epa stoves that will get the gain. Most tend to report using about 1/3 less wood rather than our 1/2. Nonetheless, using only half the wood we used to is super sweet. Sorry if I mislead anyone as I perhaps should have stated what our old stove was and it was an Ashley.

I fully understood just wanted the OP to understand.. I saw little advantage in "upgrading" a fairly new stove to another new stove.. My old CDW being an early cat stove was actually pretty darn efficient and that was before the EPA regs were established.. The new stove seems a tad more efficient but not something I can measure.. I generally burn around 3 cords a year burning 24/7, not too bad in my opinion..

Ray
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,811
Michigan
Agreed Ray.
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
raybonz said:
Backwoods Savage said:
Definitely one will not experience a big gain if trading an epa stove for another. It is in the upgrading from the old smoke dragons to the new epa stoves that will get the gain. Most tend to report using about 1/3 less wood rather than our 1/2. Nonetheless, using only half the wood we used to is super sweet. Sorry if I mislead anyone as I perhaps should have stated what our old stove was and it was an Ashley.

I fully understood just wanted the OP to understand


Same here. I was just highlighting the details of the situation for clarity.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
Backwoods Savage said:
Agreed Ray.

Don't worry we still love ya Dennis lol ...

;-)

Ray
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
raybonz said:
The new stove seems a tad more efficient but not something I can measure.. I generally burn around 3 cords a year burning 24/7, not too bad in my opinion..

Ray

I have to admit, if used T6 stoves were a little more common around here, I would definitely have an interest. The burn times on soft wood that has been reported here were really impressive.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
BrowningBAR said:
raybonz said:
The new stove seems a tad more efficient but not something I can measure.. I generally burn around 3 cords a year burning 24/7, not too bad in my opinion..

Ray

I have to admit, if used T6 stoves were a little more common around here, I would definitely have an interest. The burn times on soft wood that has been reported here were really impressive.

Certified106 has been getting long burntimes in his T-6 burning softwoods.. Very impressive!

Ray
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
raybonz said:
BrowningBAR said:
raybonz said:
The new stove seems a tad more efficient but not something I can measure.. I generally burn around 3 cords a year burning 24/7, not too bad in my opinion..

Ray

I have to admit, if used T6 stoves were a little more common around here, I would definitely have an interest. The burn times on soft wood that has been reported here were really impressive.

Certified106 has been getting long burntimes in his T-6 burning softwoods.. Very impressive!

Ray


And I think BeGreen mentioned that 10-12 hours is common as well. A T6 would fit in both locations that I am looking to upgrade. I'm not going to drop six grand in stoves, though.
 

raybonz

Minister of Fire
Feb 5, 2008
6,208
Carver, MA.
BrowningBAR said:
raybonz said:
BrowningBAR said:
raybonz said:
The new stove seems a tad more efficient but not something I can measure.. I generally burn around 3 cords a year burning 24/7, not too bad in my opinion..

Ray

I have to admit, if used T6 stoves were a little more common around here, I would definitely have an interest. The burn times on soft wood that has been reported here were really impressive.

Certified106 has been getting long burntimes in his T-6 burning softwoods.. Very impressive!

Ray


And I think BeGreen mentioned that 10-12 hours is common as well. A T6 would fit in both locations that I am looking to upgrade. I'm not going to drop six grand in stoves, though.

I hear that I paid $1850.00 for the stove and $250. for the blower not sure what the T-6 goes for..

Ray
 

Todd

Minister of Fire
Nov 19, 2005
9,407
NW Wisconsin
I'll just throw in to the mix that when I went from an EPA Hearthstone Homestead to a EPA Woodstock Fireview I went from burning 4 full cords on average, 2 years with the Homestead to 3 full cords per year on average in 5 years with the Fireview. I'm convinced cat stoves are more efficient and do save fuel in the long run.
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
Todd said:
I'll just throw in to the mix that when I went from an EPA Hearthstone Homestead to a EPA Woodstock Fireview I went from burning 4 full cords on average, 2 years with the Homestead to 3 full cords per year on average in 5 years with the Fireview. I'm convinced cat stoves are more efficient and do save fuel in the long run.

I'm convinced it has more to do with the Hearthstone.

Part of me want to by another Non-cat stove just to compare it to the Heritage. It's a small part of me that will lose to the larger part that wants to go cat for the other two stoves.
 

Todd

Minister of Fire
Nov 19, 2005
9,407
NW Wisconsin
BrowningBAR said:
Todd said:
I'll just throw in to the mix that when I went from an EPA Hearthstone Homestead to a EPA Woodstock Fireview I went from burning 4 full cords on average, 2 years with the Homestead to 3 full cords per year on average in 5 years with the Fireview. I'm convinced cat stoves are more efficient and do save fuel in the long run.

I'm convinced it has more to do with the Hearthstone.

Part of me want to by another Non-cat stove just to compare it to the Heritage. It's a small part of me that will lose to the larger part that wants to go cat for the other two stoves.

Well before the Hearthstone I had a little Regency and I went through just as much wood as the Hearthstone. I also burned 3 other steel non cats in a different home and they also burned more wood, but I was a rookie back then. Lower flue temps also help convince me.
 

BrowningBAR

Minister of Fire
Jul 22, 2008
7,607
San Tan Valley, AZ
Todd said:
BrowningBAR said:
Todd said:
I'll just throw in to the mix that when I went from an EPA Hearthstone Homestead to a EPA Woodstock Fireview I went from burning 4 full cords on average, 2 years with the Homestead to 3 full cords per year on average in 5 years with the Fireview. I'm convinced cat stoves are more efficient and do save fuel in the long run.

I'm convinced it has more to do with the Hearthstone.

Part of me want to by another Non-cat stove just to compare it to the Heritage. It's a small part of me that will lose to the larger part that wants to go cat for the other two stoves.

Well before the Hearthstone I had a little Regency and I went through just as much wood as the Hearthstone. I also burned 3 other steel non cats in a different home and they also burned more wood, but I was a rookie back then. Lower flue temps also help convince me.

Interesting. Thanks.
 
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