Hello everyone I am new to this forum. I bought a fisher Grandma bear III that is in immaculate condition. When I made the trip to get the stove the seller told me it was 30 inches wide so I was super excited to get what I thought was a grandpa bear only to get there and find it's a grandma bear. I came home with it because it is such nice shape my only concern is if it will produce enough heat for my home. It is 2500 square feet open floor plan. I am going to put a baffle in tomorrow and I have a in the flue damper as well. If anyone has any experience with this stove let me know if it will crank out the heat or if I am wasting my time and get a grandpa bear.
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Fort Wisers
Burning Hunk
That's a big home to heat but I think you'll be surprised how much heat even a grandma can crank out.
How well insulated is the home?
My brother has the grandma and is heating a good majority of a very large home with it (>4000sqft), he has a flue damper but no baffle. While rightfully a home his size calls actually for a couple of grandpas, the grandma is doing a decent job and he is happy with it.
His stove is in the basement and he can heat the basement and main floor with it quite easily.
He's in a climate that regularly sees colder then -30DegC temps for long stretches with the occasional day into the -40DegC mark. The house is well insulated.
That all being said, it's better to have a stove large enough (or even slightly larger) to meet your heating needs instead of one that's slightly under and always being pushed.
Perhaps, since you've already acquired it, start with the grandma and move to a grandpa if it doesn't work out? I'm not sure what your market is like but here a Fisher can be sold off pretty quick.
How well insulated is the home?
My brother has the grandma and is heating a good majority of a very large home with it (>4000sqft), he has a flue damper but no baffle. While rightfully a home his size calls actually for a couple of grandpas, the grandma is doing a decent job and he is happy with it.
His stove is in the basement and he can heat the basement and main floor with it quite easily.
He's in a climate that regularly sees colder then -30DegC temps for long stretches with the occasional day into the -40DegC mark. The house is well insulated.
That all being said, it's better to have a stove large enough (or even slightly larger) to meet your heating needs instead of one that's slightly under and always being pushed.
Perhaps, since you've already acquired it, start with the grandma and move to a grandpa if it doesn't work out? I'm not sure what your market is like but here a Fisher can be sold off pretty quick.
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Well I think the deciding factor is what type of house do you have? A 2500 square foot ranch is one thing. A 3 story plus basement is another thing. Is it a newer energy efficient house? A 60 year old draft palace? Then is it cathedral ceilings .........10 foot ceilings ........ 7’6”ceilings?
Then there is location ............. Alaska, California, Maine, South Carolina?
Then dry or semi dry firewood
Burning soft wood or hard wood
What kind of hardwood or softwood
Good draft or bad draft chimney
Etc., etc., etc., ...........
As you can see the factors are endless so unless someone has the exact same house as yours with the exact same Stove in the exact same climate with the exact same wood then you will not know unless you try it
!
I have both Fishers and Glacier Bay Stoves at different vacation homes. The huge Glacier Bay in Northern Maine has to fight to maintain 70 when it’s 10 below.
Frank
Then there is location ............. Alaska, California, Maine, South Carolina?
Then dry or semi dry firewood
Burning soft wood or hard wood
What kind of hardwood or softwood
Good draft or bad draft chimney
Etc., etc., etc., ...........
As you can see the factors are endless so unless someone has the exact same house as yours with the exact same Stove in the exact same climate with the exact same wood then you will not know unless you try it
!I have both Fishers and Glacier Bay Stoves at different vacation homes. The huge Glacier Bay in Northern Maine has to fight to maintain 70 when it’s 10 below.
Frank
Thanks for the reply guys. The house is well insulated, its a two story home with the top floor being a balcony with the bedrooms up there. The stove is located on the ground floor and in the middle of the house. With the balcony we have no problem with the heat rising and keeping the upstairs warm. We have two big ceiling fans on each end of the house and that really helps circulate the heat. And we are in Wyoming by Jackson hole. So we can get spells of -20 for two solid weeks. And yes we burn Dry fir firewood I don't mind aspen either once it is dry.
We have a Blaze King in the house now and what a POS! All it wants to do is smoke, with there being no air inlet on the door the only way we can even see flames is to have the door cracked, they claim it is because we have a tiled flue and it can't keep it warm enough and my reply was well I'll put a fisher in and a guarantee it will draw with a tiled flue because they will burn a fire!
We have a Blaze King in the house now and what a POS! All it wants to do is smoke, with there being no air inlet on the door the only way we can even see flames is to have the door cracked, they claim it is because we have a tiled flue and it can't keep it warm enough and my reply was well I'll put a fisher in and a guarantee it will draw with a tiled flue because they will burn a fire!
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Determine the stove type you want, then size.
Is this a glass Grandma to view the fire or isn't fire viewing important? Top or rear vent? The new style box without angle iron corners has a factory baffle and is rated higher at 1750 sf. than the old style without factory baffle at 1500 sf. Increasing the baffle size to your chimney specs will increase to more like Grandpa output for 2000 sf.
8 inch square chimney flue?
Next is ceiling height. Grandma III or IV is fine up to 1750 square feet calculated with 8 foot ceiling or 14,000 cubic feet.
Grandpa III or IV will heat 2250 sf. or 18,000 cubic feet.
XL will heat 3000 sf. or 24,000 cubic feet. That is the only model of the 3 without glass.
Is the Blaze King the King model with 8 inch outlet?
Is this a glass Grandma to view the fire or isn't fire viewing important? Top or rear vent? The new style box without angle iron corners has a factory baffle and is rated higher at 1750 sf. than the old style without factory baffle at 1500 sf. Increasing the baffle size to your chimney specs will increase to more like Grandpa output for 2000 sf.
8 inch square chimney flue?
Next is ceiling height. Grandma III or IV is fine up to 1750 square feet calculated with 8 foot ceiling or 14,000 cubic feet.
Grandpa III or IV will heat 2250 sf. or 18,000 cubic feet.
XL will heat 3000 sf. or 24,000 cubic feet. That is the only model of the 3 without glass.
Is the Blaze King the King model with 8 inch outlet?
The Grandma has cast solid doors. I don't care about watching the fire I just want my house to be warm. It is an 8 inch top vent. We have 14 feet of vaulted ceiling over the stove that is a balcony for the up stairs. We have ceiling fans that push the heat back down and spread it out nice. The flu is a 12x12 tiled with a total of 22 feet. How do I make the baffle match the chimney? The blaze king is an 8 inch flu as well thanks for all the help I have a line on a xl that would be sweet in my saddle shop
You can't use either stove with a 12 X 12 diameter chimney flue. That is the reason why you feel the Blaze King is not good.
You need an insulated chimney liner the correct size in the chimney first.
Any stove will work with a good drafting chimney, but no stove will work with a poor one. I'll explain;
Rising exhaust gasses are lighter than air and rise up the chimney. This makes a low pressure area in the flue as well as in the connector pipe and stove. This is called draft. This low pressure area is what allows the higher pressure air from atmospheric pressure to PUSH air into the stove feeding the fire oxygen. So the chimney is the engine that makes the stove go. The greater the temperature differential between inside and outside of flue, the stronger the draft, so the stronger the fire. Hence an insulated liner to stay hotter inside. The more efficient the stove, the less heat you have to leave up the stack. The outlet of a stove should be the same size all the way up. It absolutely needs to stay above 250* f. (when smoke is present during burn) to the top of chimney to prevent water vapor from combustion from condensing on flue walls. Below 250* the flue walls are wet with condensation and smoke particles stick. This is creosote. Your big problem is when hot gasses expand into a larger area they cool. This slows the draft which is why your stove now doesn't get air into the stove.
If you're not concerned about fire viewing, a single door stove such as a Papa has a 6 inch outlet and is more efficient than an 8 inch stove made for fire viewing. The less you need to lose up the stack to stay above 250* and make the stove work, the more efficient the stove, which is more heat for the INSIDE of the house. The baffle is then adjusted so the square inch area the smoke travels over the baffle matches the square inch area of the chimney flue.
To give you an idea where you are now, an 8 inch stove outlet is 50 1/4 square inches. You are increasing the area to 144 square inches. That won't work with ANY stove. A 6 inch stove is 28.26 square inches which requires almost HALF the heat an 8 inch requires so you can see how much more heat you would need to leave up a 144 square inch flue to keep it above 250* to the top. Only an open fireplace leaving almost all the heat up is the only thing that can do that. The thing to remember about chimney size is that a larger chimney doesn't have more draft, it has more capacity. However it takes more heat to create that draft. Expanding from 6 inch to 8 drops almost half the flue gas temperature (example 400* that would be OK drops to 200* which is not) so 8 round to 12 inches square drops far too much to work. That is expanding almost 3 times the size!
An XL is fine with an 8 inch insulated chimney liner, or a Papa Bear would be fine with a 6 inch insulated liner. It's all about the chimney.
They are purpose built stoves for fire viewing or a larger cooktop and longer logs in the Papa.
With the correct chimney you'll probably be satisfied with your Blaze King if it is the larger model.
You need an insulated chimney liner the correct size in the chimney first.
Any stove will work with a good drafting chimney, but no stove will work with a poor one. I'll explain;
Rising exhaust gasses are lighter than air and rise up the chimney. This makes a low pressure area in the flue as well as in the connector pipe and stove. This is called draft. This low pressure area is what allows the higher pressure air from atmospheric pressure to PUSH air into the stove feeding the fire oxygen. So the chimney is the engine that makes the stove go. The greater the temperature differential between inside and outside of flue, the stronger the draft, so the stronger the fire. Hence an insulated liner to stay hotter inside. The more efficient the stove, the less heat you have to leave up the stack. The outlet of a stove should be the same size all the way up. It absolutely needs to stay above 250* f. (when smoke is present during burn) to the top of chimney to prevent water vapor from combustion from condensing on flue walls. Below 250* the flue walls are wet with condensation and smoke particles stick. This is creosote. Your big problem is when hot gasses expand into a larger area they cool. This slows the draft which is why your stove now doesn't get air into the stove.
If you're not concerned about fire viewing, a single door stove such as a Papa has a 6 inch outlet and is more efficient than an 8 inch stove made for fire viewing. The less you need to lose up the stack to stay above 250* and make the stove work, the more efficient the stove, which is more heat for the INSIDE of the house. The baffle is then adjusted so the square inch area the smoke travels over the baffle matches the square inch area of the chimney flue.
To give you an idea where you are now, an 8 inch stove outlet is 50 1/4 square inches. You are increasing the area to 144 square inches. That won't work with ANY stove. A 6 inch stove is 28.26 square inches which requires almost HALF the heat an 8 inch requires so you can see how much more heat you would need to leave up a 144 square inch flue to keep it above 250* to the top. Only an open fireplace leaving almost all the heat up is the only thing that can do that. The thing to remember about chimney size is that a larger chimney doesn't have more draft, it has more capacity. However it takes more heat to create that draft. Expanding from 6 inch to 8 drops almost half the flue gas temperature (example 400* that would be OK drops to 200* which is not) so 8 round to 12 inches square drops far too much to work. That is expanding almost 3 times the size!
An XL is fine with an 8 inch insulated chimney liner, or a Papa Bear would be fine with a 6 inch insulated liner. It's all about the chimney.
They are purpose built stoves for fire viewing or a larger cooktop and longer logs in the Papa.
With the correct chimney you'll probably be satisfied with your Blaze King if it is the larger model.
So your message about the flu being the issue made me take an actual measurement of it. It is an 8x8 flu I assumed it was 12x12 because they said that's what is standard... I contacted the previous owner of the home and he said the blaze king would run them right out of the house so obviously the flu would draw then. The stove now acts like it can't get any inlet air once the door is shut it will smother the fire. The fisher plant here in town back in the day is just down the road from me it seemed like everyone on the valley had a fisher wood stove with a clay flu and it worked good for them. I have a friend here in town he has a 12x12 flu and he has a grandpa bear and it draws like a freight train. All the old timers claim the bigger the flu the bigger the draw but how you put it makes sense it's not going to draw bigger it's just larger capacity. Anyways I think with our being and 8x8 we should be good and the flu runs smack dab in the center of my home so it should always be warm. So Coaly do you think the grandma bear will heat that much home or will I be wasting my time and just find a larger one? I like the double door look better than the single bear series and they fit better in my house.
Well that's a lot better. 12 X 12 is for a fireplace.
Knowing the fundamentals now you can see how much more heat is necessary to leave up a flue to keep flue gas temp above 250* to the top. A taller chimney will create more draft as well, but requires more heat to do so since it cools at it rises. His 12 X 12 cools and needs more frequent cleaning or he is leaving so much heat up, the stove can't heat as large of an area as it should. Draft is the strongest at flue collar on stove and strength goes by the average flue gas temperature and differential temperature outside the flue. So when allowed to expand and cool it is very detrimental to overall draft. The smaller the stove, the more critical heat loss becomes. He would go through a lot less wood with a liner the correct size. Many times people have smaller stoves connected to large chimneys that can't heat the indoor area they are trying to heat, and when they understand the basics, reducing the size of heated area in the chimney they don't need, the stove heats up properly and drives them out.
I would look for a larger stove. Your height and square footage is too much for your Grandma. BTU output goes by the surface temperature of each square inch of surface area. So running a hotter stove makes up for the lack of surface area. But that is shorter duration fires. For coals in the morning you'll want a larger firebox. Grandpa not only has more surface area, it holds more wood for a longer burn.
Make sure you have no air leaks into your chimney flue now. Any leak like a poor fitting clean out door allows cool air to leak into the low pressure area of flue cooling the flue and slowing draft. Spark screens at the top clog since cold outdoor air can condense water vapor allowing particles to stick on screen. Make sure any connector pipe elbows are clean, it's acting like a restriction somewhere. Is the BK a CAT stove?
Also make sure the pipe where it goes into chimney, called the breech, isn't pushed too far into the chimney blocking off the flue gasses. The thimble and pipe should be flush with the inside of flue wall. I assume the flue liner is clean.
I see you're up there in elevation 6 to 7000 feet too. The higher you go, the less atmospheric air pressure you have pushing into the intakes, so like a normally aspirated engine, power drops with altitude the same as less air getting into stove.
Was your local fabricator in Jackson Wyoming?
Knowing the fundamentals now you can see how much more heat is necessary to leave up a flue to keep flue gas temp above 250* to the top. A taller chimney will create more draft as well, but requires more heat to do so since it cools at it rises. His 12 X 12 cools and needs more frequent cleaning or he is leaving so much heat up, the stove can't heat as large of an area as it should. Draft is the strongest at flue collar on stove and strength goes by the average flue gas temperature and differential temperature outside the flue. So when allowed to expand and cool it is very detrimental to overall draft. The smaller the stove, the more critical heat loss becomes. He would go through a lot less wood with a liner the correct size. Many times people have smaller stoves connected to large chimneys that can't heat the indoor area they are trying to heat, and when they understand the basics, reducing the size of heated area in the chimney they don't need, the stove heats up properly and drives them out.
I would look for a larger stove. Your height and square footage is too much for your Grandma. BTU output goes by the surface temperature of each square inch of surface area. So running a hotter stove makes up for the lack of surface area. But that is shorter duration fires. For coals in the morning you'll want a larger firebox. Grandpa not only has more surface area, it holds more wood for a longer burn.
Make sure you have no air leaks into your chimney flue now. Any leak like a poor fitting clean out door allows cool air to leak into the low pressure area of flue cooling the flue and slowing draft. Spark screens at the top clog since cold outdoor air can condense water vapor allowing particles to stick on screen. Make sure any connector pipe elbows are clean, it's acting like a restriction somewhere. Is the BK a CAT stove?
Also make sure the pipe where it goes into chimney, called the breech, isn't pushed too far into the chimney blocking off the flue gasses. The thimble and pipe should be flush with the inside of flue wall. I assume the flue liner is clean.
I see you're up there in elevation 6 to 7000 feet too. The higher you go, the less atmospheric air pressure you have pushing into the intakes, so like a normally aspirated engine, power drops with altitude the same as less air getting into stove.
Was your local fabricator in Jackson Wyoming?
Yes the BK is a cat stove and I suspect that's where the issues are and BK told me I can not buy parts for the particular model and to buy a new one I said perfect fisher here I come. The manufacturer was in Afton Wy. They were the largest at one time producing 13 a day. You should see the new old stock they have of parts and stoves. Too bad it's all tied up in the courts. The patriarch of the family passed away and now all the siblings are suing each other for everything. I will go through my whole chimney like you said to see if I find anything out of place. I will put a grandpa bear or the xl in. I sure do appreciate all of your help. Do you have plans for a baffle for a Grandma bear?
Have you had the flue checked? A clay lined chimney that has been heated with for thst long could be in pretty bad shape. You should also check to see if it has the required 2" of clearance to combustibles the whole way before you put a stove in that is going to put allot more heat up that old chimney.
Honestly i would look into getting that bk working. It is much more efficent. You will use much less wood.
Honestly i would look into getting that bk working. It is much more efficent. You will use much less wood.
You can get generic catalytic converters here; (broken link removed)
Fisher research and development designed baffles for the 1980 double door stoves to reduce smoke particulate. No single door stoves from the Bear Series had them installed factory, but I tried each model on the same test chimney and the results are here;
https://www.hearth.com/talk/threads...d-fisher-more-heat-less-smoke-under-25.74710/
Only follow the design, the actual measurement can vary since all fabricators did things their own way to the extent of even making stove bodys wider and some have an optional second course of brick....... barometric stoves were made with an air intake box on the back, just too many variations to give measurements. Plus the baffle needs to only close off no more than the chimney diameter in square inches. So someone using a 7 or 6 inch chimney would make a larger plate so the opening above it matches their flue. a chimney larger than the outlet shouldn't be baffled much at all since it requires more heat than necessary to be left up the chimney. You can't make a stove more efficient without an efficient chimney to start with. The baffle is adjusted for the chimney, not the stove just like adjusting a flue damper controls the chimney, not a specific setting for a stove model. Simply raise the front of baffle to close the space above it to the opening desired. That baffle thread was written for the single door stoves but can be adapted to double doors.
Fisher research and development designed baffles for the 1980 double door stoves to reduce smoke particulate. No single door stoves from the Bear Series had them installed factory, but I tried each model on the same test chimney and the results are here;
https://www.hearth.com/talk/threads...d-fisher-more-heat-less-smoke-under-25.74710/
Only follow the design, the actual measurement can vary since all fabricators did things their own way to the extent of even making stove bodys wider and some have an optional second course of brick....... barometric stoves were made with an air intake box on the back, just too many variations to give measurements. Plus the baffle needs to only close off no more than the chimney diameter in square inches. So someone using a 7 or 6 inch chimney would make a larger plate so the opening above it matches their flue. a chimney larger than the outlet shouldn't be baffled much at all since it requires more heat than necessary to be left up the chimney. You can't make a stove more efficient without an efficient chimney to start with. The baffle is adjusted for the chimney, not the stove just like adjusting a flue damper controls the chimney, not a specific setting for a stove model. Simply raise the front of baffle to close the space above it to the opening desired. That baffle thread was written for the single door stoves but can be adapted to double doors.
Sounds great I sure appreciate it. I am going to get to it today. I will let you know what I find.
I checked my flu and there were no leaks. There was however some build up not enough I thought would drag on the draw I cleaned it completely and she draws like a freight train the BK stove works much better and does not smoke how ever in order to get it hot and roaring the door has to be open then once it is shut it cuts the air intake off I cleaned it all out and took the fire brick and all the thermostat parts off the back and cleaned them to make sure there wasn't build up in it that was cutting my air intake down and there wasn't. I burned it one night and it kept the house warm and held a fire for about 6-8 hours on a load of pine. So last night I hooked up the Grandma bear fisher and all I have to say is WOW now thats a heater! It gives off twice the heat and as just as efficient. It was-20 last night I went through the same amount of wood with the fisher as the blaze king but the fisher gave off twice the heat and uses the same amount of wood it kept my home 75+ all night which is warmer than I like but it was nice. I sure do appreciate all the help and input from everyone. Now my next project is to put 2 xls in my indoor arena!
A round insulated flue would probably make a difference with the BK. (both actually) They were starving for air.
You are in "Starvation Valley" you know.
Reduce the XL from 10 inch at the stove to 8 with an insulated 8 inch "pack'" type chimney.
You are in "Starvation Valley" you know.
Reduce the XL from 10 inch at the stove to 8 with an insulated 8 inch "pack'" type chimney.
Yes Sir I know that well. My ancestors settled the valley here in the late 1800's and gave it the nickname. Do you know where a good place that will nickel plate my xl doors? Mine are just black.
How old is the cat? Is it getting active? There is absolutly no way an old fisher should outperform a bk cat stove if it is working properly. Fishers are good stoves for what they are but they are very primative
It depends on what you consider "out performs" in heat level the fisher will crank out way more heat it may burn a little more wood but that's the last of my concern. The cat is brand new and everything is working as it should. The stove is only rated at 51,000 BTU on high, and it's the king model, that's not much. With the door on the stove cracked it really gets going good but with it shut and the by pass closed heck it will bearly stay warm enough to hold a flame. These new stoves are like our new diesel pick ups and tractors they have some much emissions bs on them they are so choked down they can't even run. In my opinion the only new stove worth buying is a harman legacy coal stove. Once a guy burns coal you never go back to wood I wish my dealer could get me one in by the end of winter because that's what I would have.
It isnt supposed to have flame. The box smoulders and the cat burns off the smoke. But yes you are right it does not have anywhere near the peak heat output of a fisher. But the bk will put out even heat for hours on end. Old stoves like fishers will not. Even non cat tube stoves give off much more even heat much longer. As far as never going to wood after coal that is rediculous. I switched from coal and would never think of going back to coal. And we have many customers that have done the same. I personally cant stand the dirt and smell of coal. Btw we also have many that have switched to coal it is personal preference.
I will tell you the majority of people who have problems with modern stoves either are not running them properly or are not feeding them good fuel.
Oh and yes the king is only rated for 51000 btus but that is for 12 hrs of constant 51000 btus. If you open up the thermostat more it will put out more heat than that.
jatoxico
Minister of Fire
Anyone who's spent any time here has heard this or similar many times and then seen the change after getting things straightened out so you ain't the first, in fact most of us had at least some trouble running EPA stoves at first.
If you can't get the Blaze King to keep a lively fire it's draft and maybe more likely, the wood. In that case the BK can't put out the BTU's it's rated for.
The Fisher will be much more forgiving when burning wet wood but it too would be happier with better fuel. The fact that your draft changed after a chimney a cleaning is more evidence the wood is at least part of the problem.
Coaly who has given been posting on your thread has given instructions to make baffles for Fisher stoves on the cheap that help you getter better efficiency from it but I wouldn't give up on the BK. Given good wood it can do things the Fisher will never be able to do.
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