Cat stove questions

What do you mean when you say the stove goes out? 90% of the time I have no flame in the box; as long as the cat stay active we're doing good.

Right. It's quite different from conventional stoves. We can't rely on the appearance of the fire, but on the temp. reading . Hopefully your manual contains some more specific temperature guidelines for cat. operation.

Not normal. Walk us through your startup routine and at what time you close the bypass and what temps you see on the cat and how much air you leave open.

The incomplete burn is either from lack of air or wood was too wet. I would try giving it a tiny bit more primary air and see what you end up with.

Mstech3 said:

in morning the ends of the log usually the front one are still in fire box they are like wood lunp charcoal all black but still in tact around 3"x5" to as small as 2"x3".

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Sounds like wet wood. Dry wood will want to burn down to ash. More air will help.

Mstech3 said:

So I start the fire with about 5 to 8 prices of oak kindling about 8% moisture bypass open and all air inlets open all the way after they get going good (cat temp around 250 300) put on some wood logs (around 15%moisture) usually 2 logs let them get burning then turn off the front (shotgun air) once the cat hits 500 I wait about 20 min then close cat and start to close off the primary air controls usually leave about .25 inch open on both. About 1.5 hours into this the cat is reading 1300 to 1500 so I close one primary air off (one still open about .25") no flames left in fire box in about another 1.5 to 2 hours open bypass open door put another log or two on close door and close bypass usually open shotgun air to get log burning or leave door open for a bit. Cat temp around 1200 1400. Leave one primary air open around .25" and let burn after burning all night and opening stove in morning the ends of the log usually the front one are still in fire box they are like wood lunp charcoal all black but still in tact around 3"x5" to as small as 2"x3". I live in Ohio and like I said I just put the stove in have not had it burning all day yet not been cold enough usually start it around 6pm so have not had a significant fire yet (all day long) wondering if that is my problem?

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That sounds OK but how are you checking the moisture content of your fuel? To get an accurate reading, you should have several representative splits, small and large, at room temp. Then split these and check with the moisture meter, jabbing the pins firmly into the freshly-exposed face. Your cat temps sound good; I don't like to see them much higher than that. Stay under 1800, in any case. After you load the fuel, wait for it to get burning a bit to expel the initial moisture, before closing the bypass again. You don't want to shock the combustor with wet steam when the cat is hot. Also, if the cat is still hot I usually open the bypass for several minutes to let it cool, before opening the door to load. But it sounds like your cat is lit after you reload, so that's good. I've described how I run the stove (the larger Buck 91) in several threads. Usually I have 700-900 on the cat probe before closing the bypass, to assure a good light-off. The probe might go to 1400 or so, then slowly drift down as the load coals and less smoke is available for the cat to eat. Following is a link to a recent thread where I outlined my procedure.
As far as the wood going out, other than moisture being a bit higher than ideal, it could be a draft issue. Draft will be less in warm weather. How tall is your chimney, and do you have a full stainless liner installed to the top?
https://www.hearth.com/talk/threads/question-for-those-with-cat-stoves.153187/

Mstech3 said:

any feed back on the quality of the buck stoves?

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Not familiar with the 80ZC, but I like the 91. Built solid, I like the air controls, door latch assembly, usable ash dump, etc. Yes, I would call it a quality stove.

Mstech3 said:

I was under the impression that the more air I let in the fire the more fire I would get and the hotter the cat would get. So I must have this all backwards the way I understand you to say it is the less air I put into the fire the more smoke

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No, you have it pretty much right. There are a lot of variables determining how much smoke will be available for the cat. After you load, the more wood you get involved, the more smoke there will be for the cat. But if you are running a little bit of flame in the stove, the flame will be burning some of the smoke and there won't be quite as much for the cat to eat. Softer, lighter woods like soft Maple will burn and gas faster and the cat will get hotter. The outside temp will affect the amount of draft, so with colder temps you might need to cut the air a little more to achieve a similar burn rate to when it's warmer out. I really think you are doing OK. With any new stove, there's a learning curve as you experiment and discover how to get the stove to do what you want. Make sure you have dry wood, and go from there.

I have a Buck 94NC and it is the Buck 91 with burn tubes instead of a cat. We really like the stove a lot as well. Solidly built, cranks out the heat, & has a usable ash dump as mentioned. I just have one air control so I have to play with mine a tad more to sustain the heat and get a thorough burn. As my fire burns down, I have open the air back up some.. That being said, it is a pretty solid stove. I sometimes get pieces that do not burn up as you mentioned in one of your posts, but that I have found to be an issue of not having enough air, as was also mentioned.
Let us know if you have any other questions. By the way, welcome to the forums!.

I'm not familiar with the 80 either, but our 91 heats like a mammajamma. We've had it as the primary heat source for our1800 sqft house for 8 years. There was a learning curve to get the most out of it. Early on, I had the same problem as you, having wood and/or charcoal left the next morning, so I went back and reread the manual. I'd been closing the primary air off too much. I read a little of the 80 online manual, concerning burn rates, it's the same as for the 91. One difference between the 80 and 91, the 80 has 2 primary air controls, one for each side. The 91 has one control for both sides. Below is a cut and paste for burn rates. Note that in all the settings the primary air controls are maintained as a pair. I close the shotgun air on mine ASAP, then per the manual, reduce the primary air control to get the burn rate I'm looking for. I also do as the manual says and close the bypass immediately after loading. I don't know the moisture content of the 2 year old split red and white oak and hickory we burn, it's kept under a shed. I load it for an overnight burn about 8ish, and by 9 or so it's set for the night. The next morning the temp is still above 500, with more than enough coals to fire off the fresh wood load. The company that installed it check it out every fall. Great stove. Hope this helps. Mark


BURN RATES


A. Low Burn Rate: Set primary air controls (both) almost closed - leave open about 1/8". Set rheostat for fan

control between low to medium speed. This burn rate is most desired and most efficient, but can only be

achieved after a fire has been established and burning on its own controlled air. Close the bypass damper (push

in).

B. Medium-Low Burn Rate: Partially close primary air controls (push halfway in). Close bypass damper (push

in). Set the rheostat for fan control halfway between low and high.

C. Medium-High Burn Rate: Set primary air controls almost fully open. Close bypass damper. Set rheostat for

fan control between medium position and high position.

D. High Burn Rate: Set primary air controls wide open. Have damper closed. Set rheostat for fan control all

way on high. USE CAUTION! Close shotgun air control after 5 minutes.

E. Wood Loading: During refueling, open (pull out) bypass damper to allow smoke in the firebox to escape -


wait a few seconds, slowly add wood. Immediately close door and bypass damper. Open primary air control

wide open for 2 minutes to charge wood. After most of wood has burned and if you are not planning on

reloading immediately, it may be necessary to open damper bypass, then door, and rake wood and coals into a

pile near front center of firebox. (Be certain wood chunks are pulled out of rear corners.) Close door and

damper bypass. This step will assure continued combustion and thorough burning of wood.

You will have to experiment with fire rate until you find the particular setting for heating your home. Chimney drafts,

tightness of house, doors, windows, insulation in house and atmospheric conditions all influence which setting you

must have, so it may take several firings to learn setting necessary for your installation. Heating capacity is based on

BTU output and conditions listed above. These conditions will affect heating capability of your heater

Woody Stover said:

That sounds OK but how are you checking the moisture content of your fuel? To get an accurate reading, you should have several representative splits, small and large, at room temp. Then split these and check with the moisture meter, jabbing the pins firmly into the freshly-exposed face. Your cat temps sound good; I don't like to see them much higher than that. Stay under 1800, in any case. After you load the fuel, wait for it to get burning a bit to expel the initial moisture, before closing the bypass again. You don't want to shock the combustor with wet steam when the cat is hot. Also, if the cat is still hot I usually open the bypass for several minutes to let it cool, before opening the door to load. But it sounds like your cat is lit after you reload, so that's good. I've described how I run the stove (the larger Buck 91) in several threads. Usually I have 700-900 on the cat probe before closing the bypass, to assure a good light-off. The probe might go to 1400 or so, then slowly drift down as the load coals and less smoke is available for the cat to eat. Following is a link to a recent thread where I outlined my procedure.
As far as the wood going out, other than moisture being a bit higher than ideal, it could be a draft issue. Draft will be less in warm weather. How tall is your chimney, and do you have a full stainless liner installed to the top?
https://www.hearth.com/talk/threads/question-for-those-with-cat-stoves.153187/

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Woody , that was I who posted that question and I am sorry I am just now getting around to thanking you for your detailed reply. Been under the weather for a bit. I will read your reply this evening and if I have any comments/ question, I will post more. Based on your other posts and replies I think you must have covered it pretty well, seeing how long and detailed it must be.

Can't thank you enough..

Mstech3 said:

I am burning silver maple and it seems to get the cat VERY HOT when I first load the wood in it was cut last year I was wondering if there is a good link to see what woods burn the best in cat stoves?

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As bholler said, all woods burn well in a cat stove, but they burn differently. The softer woods will catch fire and gas faster after you reload. You can usually shut the air down sooner on a reload of soft Maple, etc. When reloading with denser woods like Oak or Hickory, it will take longer to burn in the load and get it gassing enough to fire off the cat quickly when you close the bypass. You can't rush it. But once the cat is lit and the air is cut, the cat will stay active longer on the dense woods.