Grandpabear Woodstove

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jaimiewonder

Member
Oct 15, 2016
15
maine
Hello i need some suggestions on a baffle or how to make my new stove more efficient.I also was hoping i could get more info about my new stove.I has the silver balls on the feet...you just cant tell in the picture.

Im gonna go with not UL approved and not extra heat shields.
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Move to the Fisher forum. There are some examples of baffle installation here and threads on ID.
 
Hello i need some suggestions on a baffle or how to make my new stove more efficient.I also was hoping i could get more info about my new stove.I has the silver balls on the feet...you just cant tell in the picture.

Im gonna go with not UL approved and not extra heat shields.
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What do you mean by not ul approved and not extra heat shields? Do you mean you are sticking with the 36" clearance required?
 
What do you mean by not ul approved and not extra heat shields? Do you mean you are sticking with the 36" clearance required?
I was asking if maybe it was one of the not lable ul safety ones but still was...just not listed.Yes the UL ones you could get closer to the wall i believe...
 
I was asking if maybe it was one of the not lable ul safety ones but still was...just not listed.Yes the UL ones you could get closer to the wall i believe...
If it doesn't have a tag it isn't listed legally. And technically even with a tag if you put a baffle in it the listing would be void. But yes a baffle will increase the efficiency some. But still very low efficiency compared to more modern stuff.
 
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If it doesn't have a tag it isn't listed legally. And technically even with a tag if you put a baffle in it the listing would be void. But yes a baffle will increase the efficiency some. But still very low efficiency compared to more modern stuff.
Listed legaly and as safe as a listed on are 2 different thing.....
 
Listed legaly and as safe as a listed on are 2 different thing.....
Not when insurance is involved. And a baffle will without question change the heat characteristics of the stove making the listing irrelevant
 
Im aware of that part....Just need to know the safety of the stove....Yes i know its not the stove that makes it safe but the user...
 
Im aware of that part....Just need to know the safety of the stove....Yes i know its not the stove that makes it safe but the user...
Actually it is the install as much if not more than the user or stove.
 
Im aware of that part....Just need to know the safety of the stove....Yes i know its not the stove that makes it safe but the user...
And honestly there is no real difference between a listed and unlisted grandpa. Just the tag and testing
 
install and use go hand and hand.I have a papa bear...its being replaced with the grandpa bear.I have only 2 sheets of tile board behind it and under it.I cant do a 8 inch pipe so for now i have to use the 6 inch double walled going through a horizontal with a thimble.I heard some 80s where left overs...and just as safe...just didnt have the legal part going on.
 
I think this is what i read


Many fabricators continued to produce the old style stove with angle iron corners that was not UL Listed $100 cheaper than the Listed model for installation on non combustible hearth.
 
I think this is what i read


Many fabricators continued to produce the old style stove with angle iron corners that was not UL Listed $100 cheaper than the Listed model for installation on non combustible hearth.
No difference safety wise
 
install and use go hand and hand.I have a papa bear...its being replaced with the grandpa bear.I have only 2 sheets of tile board behind it and under it.I cant do a 8 inch pipe so for now i have to use the 6 inch double walled going through a horizontal with a thimble.I heard some 80s where left overs...and just as safe...just didnt have the legal part going on.
Use and install are 2 completely different things. If installed correctly you can fun the stove full blast as long as you want and not have the house in danger untill the stove is damaged. If it is installed in an unsafe manner it doesn't matter how you run it there is always a risk to the home.
 
One Grandpa bear for sure has extra heat sheilding....i swear im not crazy.
Yes and that reduced clearances further. But there are unsheilded ones that are listed. If yours is shielded that would be easy to see so no question what it is for safety reasons
 
Coaly will be along at some point to tell us who is right. I know I have worked on Grandpas that had a tag and no sheilds though
 
Honestly i dont know...i dont think so...was it just thicker body?...or a second layer with a gap between.Im also wondering about the Concord NH and being stove doors 006 ...wasnt sure how mant where marked this obviously.
 
The difference is the older style with angle iron corners (I) was tested by 4 different labs across the US before standardized testing by UL was adopted as the national standard. So they are safe.... Just not listed. The models tested to UL Standard is the Roman Numeral III. They have bent corners in front, and integral heat shields. As you read, many fabricators continued to make the unlisted version for where UL listing was not required on and near non-combustible materials such as on fireplace hearth or cement basements. They were $100 cheaper. This is when you find an arched type door installed after 1979 on an old style box. This shows the stove was made after ‘79 when the newer doors, on an old style box.

Installing this stove to the reduced clearance as given in NFPA 211 for unlisted stoves is safe. If your jurisdiction has adopted the International Codes, they technically require all appliances to be listed. This requirement is for a new installation, so many still buy and install, claiming they were existing before the new International Codes were adopted. Older installs are grandfathered and difficult to tell when they were installed. So enforcement is by many insurance companies requiring UL tags as well.

As far as a baffle, use 5/16 thick steel. Make a cardboard template to sit on rear shelf, aim on an angle upward at front towards lower bend. The openomg space smoke travels through can be no smaller than chimney flue internal square area. Insulated liners can use the minimum smoke space, larger chimneys requiring more heat need a larger smoke space. This is easily adjusted by lowering baffle at front slightly opening the space. I set firebrick on edge and set baffle plate on brick corners. Moving bricks fire and aft raises and lowers baffle. Sometimes you have to nip corners on an angle to lower more. Once adjusted where you have the desired chimney temp, I bolt or weld angle iron on the baffle edges to prevent bricks from tilting inward. Not a difficult install. The lower front top will then get hotter than the rear upper, preventing excessive heat loss up chimney as well as temp spikes making it much more controllable.
 
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The difference is the older style with angle iron corners (I) was tested by 4 different labs across the US before standardized testing by UL was adopted as the national standard. So they are safe.... Just not listed. The models tested to UL Standard is the Roman Numeral III. They have bent corners in front, and integral heat shields. As you read, many fabricators continued to make the unlisted version for where UL listing was not required on and near non-combustible materials such as on fireplace hearth or cement basements. They were $100 cheaper. This is when you find an arched type door installed after 1979 on an old style box. This shows the stove was made after ‘79 when the newer doors, on an old style box.

Installing this stove to the reduced clearance as given in NFPA 211 for unlisted stoves is safe. If your jurisdiction has adopted the International Codes, they technically require all appliances to be listed. This requirement is for a new installation, so many still buy and install, claiming they were existing before the new International Codes were adopted. Older installs are grandfathered and difficult to tell when they were installed. So enforcement is by many insurance companies requiring UL tags as well.

As far as a baffle, use 5/16 thick steel. Make a cardboard template to sit on rear shelf, aim on an angle upward at front towards lower bend. The openomg space smoke travels through can be no smaller than chimney flue internal square area. Insulated liners can use the minimum smoke space, larger chimneys requiring more heat need a larger smoke space. This is easily adjusted by lowering baffle at front slightly opening the space. I set firebrick on edge and set baffle plate on brick corners. Moving bricks fire and aft raises and lowers baffle. Sometimes you have to nip corners on an angle to lower more. Once adjusted where you have the desired chimney temp, I bolt or weld angle iron on the baffle edges to prevent bricks from tilting inward. Not a difficult install. The lower front top will then get hotter than the rear upper, preventing excessive heat loss up chimney as well as temp spikes making it much more controllable.
And there you have it.

Were there ever unsheilded Grandpas with tags? Or was someone here putting tags on stoves where they didn't belong? Which is certainly possible.
 
You’re both right. There were a few early stoves in 78 and 79 tested to UL criteria shown on manuals with no tags, some were tagged. Back then listing was not a big deal. If you have one with a tag, great, it’s listed. Without a tag is considered unlisted today. Fisher started advertising them as listed as it caught on, and some other companies had theirs tested. Smaller companies couldn’t afford it, so many were not. Not many insurance companies were asking for it, and when tags were running low, some went out without tags. If a customer needed one at a later date, one was given to them. It was a time when stoves couldn’t be made fast enough or always keep up with tags.

UL testing includes such things as surface temp of controls, sharp edges, corner radius ..... lots of things other than the benchmark temperature testing with moveable walls for the clearance that will be required.
 
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