Non-cat to cat insert wood consumption

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creek chub

Member
Sep 28, 2015
106
Va
I’m looking for any feedback from members who switched from a non-cat insert to a cat insert.

I’m curious an estimated amount of less burned wood per year with the new cat models.

Any feedback and comments would be appreciated
 
Zero in my opinion. Each piece of wood holds the same amount of btu. The difference between the two types of stoves is how that btu (from that piece of wood) is released into the room.
 
In a warmer climate like Virginia you will get more out of a cat stove since you will be burning low and slow a lot which is where a cat stove shines. When it's colder out a cat stove doesn't save you anything as it's no different than any other modern stoves when running high.
 
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What insert do you have now?
 
I don’t have one now. There are some used non-cats listed on FB but I’m leaning towards a new cat model.
In VA the only reason I see for a cat model is the the tax credit on an eligible install. Heat pump in combination with secondary combustion stove works really well and will save more wood than running a cat stove on low. If wood is free it it will cost more to run heat pump but if buying wood running heat pump down to 40 degrees is probably cheaper.
 
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In VA the only reason I see for a cat model is the the tax credit on an eligible install. Heat pump in combination with secondary combustion stove works really well and will save more wood than running a cat stove on low. If wood is free it it will cost more to run heat pump but if buying wood running heat pump down to 40 degrees is probably cheaper.
Our house heat is natural gas. Hopefully I get back to burning wood again next fall. I have access to cut as much firewood as I need. Right now I have about 2.5 years split and stacked up.
 
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Efficiency wise as diabel said, there is not an appreciable difference between modern tube and cat stoves/inserts.

However, most cat stoves can turn down a bit lower, so if one wants to burn in shoulder seasons one can do so without a pump and glide temperature oscillation (short hot fire followed by a longer slow cool down - temperature swings). One might therefore burn a bit longer if one is so inclined with a cat stove, leading to a yearly wood usage that is higher than if one would revert to e.g. a heat pump in the shoulder season.

So, rather than asking what's more wood-usage-efficient, ask yourself what your burning mode would be. "All heat from wood", or "most heat" (mostly in the colder weather) from wood. And how even do you want the temperature to be during a day.
If the former (all heat), a cat stove that can provide high heat when it's cold but also turn down more to provide a lower level of heat in addition to the higher level used at colder weather, is nice. If the latter, a tube stove might be better (the advantage of a cat stove is gone when one doesn't also run low).
 
Efficiency wise as diabel said, there is not an appreciable difference between modern tube and cat stoves/inserts.

However, most cat stoves can turn down a bit lower, so if one wants to burn in shoulder seasons one can do so without a pump and glide temperature oscillation (short hot fire followed by a longer slow cool down - temperature swings). One might therefore burn a bit longer if one is so inclined with a cat stove, leading to a yearly wood usage that is higher than if one would revert to e.g. a heat pump in the shoulder season.

So, rather than asking what's more wood-usage-efficient, ask yourself what your burning mode would be. "All heat from wood", or "most heat" (mostly in the colder weather) from wood. And how even do you want the temperature to be during a day.
If the former (all heat), a cat stove that can provide high heat when it's cold but also turn down more to provide a lower level of heat in addition to the higher level used at colder weather, is nice. If the latter, a tube stove might be better (the advantage of a cat stove is gone when one doesn't also run low).
Thanks for the information and detailed explanation

Wood will be our primary heat source. It sounds like the cat option has a bit more control for times when less heat is needed. Worst case with a cat option is running it at higher settings when temps require it which sounds like it equals out to a non-cat insert.
 
Just remember if your wife and family wants to see Fire :ZZZ get a regular stove with secondary's, Because a cat stove the glass will get black overnight burning on low or medium levels And it's a pain in the a-ss to clean off. My BIL who lives 4 house's down from me bought cat stove and his wife hates it, She spends more time at my house because she likes to view the fire. I'm running a Pacific Energy No dirty glass at all. I just build a smaller fire with lower BTU wood - Pine-Spruce- Cottonwood- boxelder when it's warmer outside. You can't do that with a cat. And yes we burn about the same amount of wood.
 
Thanks for the information and detailed explanation

Wood will be our primary heat source. It sounds like the cat option has a bit more control for times when less heat is needed. Worst case with a cat option is running it at higher settings when temps require it which sounds like it equals out to a non-cat insert.
Note that there can be quite a difference in burn times and low output between a pure catalytic stove and a hybrid.

Does the house have a heatpump? If so, mild weather heating may be better done by it. Draft gets much weaker as the outdoor temperature goes up above 50º, especially if the chimney height is one story.
 
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Not all cat stoves/inserts are the same either. A lot do not turn down low enough that even on low you will see any difference on wood usage. And as mentioned hybrids are included in that.

The ones that do however will run very low and last a long time on a load of wood for when you dont need a lot of heat.
 
I just build a smaller fire with lower BTU wood - Pine-Spruce- Cottonwood- boxelder when it's warmer outside. You can't do that with a cat. And yes we burn about the same amount of wood.
Are you saying you cant do small fires in a cat stove? I agree that wood usage will be similar but you might find a few folks on here that burn plenty of small hot fires in their cat stoves albeit mine is a hybrid.
 
Both will require electricity to run the blower. Keep that in mind. Apologies if it was already stated.
 
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The cat stove has fire visible when one is not burning low.
When burning low (20-30 hrs without any flame), my window does not turn all black; I can still see fire immediately if I turn it up. Yes, 1/2 the window is black then (left and right, starting in lower corners), but I've not had more than half the window black.

yes, one can burn a small hot fire in a cat stove (to see flame) and then let the room temp slowly cool down until the next small hot fire.
But this negates the advantage of a cat stove. If that is what you want, get a tube stove instead. No reason to have a cat stove.
 
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Note that there can be quite a difference in burn times and low output between a pure catalytic stove and a hybrid.

Does the house have a heatpump? If so, mild weather heating may be better done by it. Draft gets much weaker as the outdoor temperature goes up above 50º, especially if the chimney height is one story.
No heat pump, forced air gas
 
I went from a Jotul C550 (non-cat) to a Lopi Med Flush NexGen Hybrid (cat). Both inserts have similar sized fireboxes (around 2.3 cu.ft). I can confirm a lot of what has been said above, but the cat's ability to extend the burn time is a true advantage. With the Jotul, I might've gotten five, maybe six hours of burn time/heat. With the Lopi, I'm much closer to eight. I'll start a fire at 11pm, engage the cat, cut back on the air and wake up at 6:30am to a tremendous amount of coals and a house still warm enough so that the furnace hasn't had to fire up (or doesn't have a huge temp delta to make up for). I'll set up another full fire and engage the cat/cut the air for the morning. My kids come home from school to a warm house, and the furnace again hasn't really had to make up a huge temp delta, if fires up at all. They don't mess with the insert, so another fire has to wait until I get home in the early evening, which I do small and hot. Then I set up for the next cycle- a full fire overnight at 11pm, etc... In a 24 hr period, I've set up two full fires, one smaller one and my furnace has fired up for only a few hours in the mid/late afternoon. While I really loved the C550 (much prettier cast iron surround, quieter fans, less rattling, heat blasting the living room to 80F+), I definitely burned more wood and fossil fuels with it. Of course, YMMV.
 
It’s a fairly tall chimney. I haven’t measured it yet but say it is close to 30ish feet and is insulated

You need a damper and hope that one is enough
 
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It’s a fairly tall chimney. I haven’t measured it yet but say it is close to 30ish feet and is insulated
That will work ok with a straight-cat stove, perhaps even in milder weather. The Woodstock Fireview/Palladian/Keystone and all BK stoves are straight catalytics. Some Buck stoves are too.
 
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