Questions about a Grandma Bear

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Frankferter

Member
Jan 28, 2017
2
Portland, OR
From what I can tell, I have a Grandma Bear, pre 1980. This manual is what I used to decide this: https://www.manualslib.com/manual/1006796/Fisher-Stoves-Grandma-Bear-Iii.html?page=13#manual
It's not exactly this, but close.

We bought the house and the previous owner put it in, but I'm not sure that what he did to the inside is correct.

I have a few questions:

- The outside seal, where the doors fit in, have a gasket. I've assumed that was needed so I've replaced it. Is it true these stoves don't need it? (BTW, I've tried it without and the doors don't shut quite correctly and snug, but maybe there is another way to make this work?)
- There are two levels of bricks on the walls right now. The first level is as shown in the manual above. Then there is a second level on top of that. Then he put in a "roof" on top of that with fire-retardant boards. Is the second level and roof needed at all? The manual doesn't show either of those.
- The latch on the right side now won't cinch the door tight. It looks like the iron piece inside that the handle grabs onto has been bent over time. What is the best way to bend it back to it's original shape or is there another option?

Thank you!
 

coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,667
NE PA
The second course of brick was optional starting in 1977. It was added to raise the firebox temperature for a cleaner burn, probably the same reason a previous owner added more to the top of yours. Fiberboard baffles didn’t exist back then. You want the heat to rise to the top and radiate into the area as well as heat the cooktop. (Unless you are looking at a baffle that the exhaust has to travel around to get out).

The solid cast iron doors did not use any gasket material. The channel iron welded to stove front is the door seal. The center of iron channel makes contact with the raised portion on the back of door. The edges of channel iron makes contact with the back of door. This creates 3 points of contact all the way around the opening. Considered air-tight as built. (the first double door stoves in ‘76 used round steel rod seal with a round edge cast into doors)

When hinge plate holes become worn, or hinge pins wear from no lubrication, doors can become loose enough for gasket material to fit in the groove of channel iron. There is normally no clearance for gasket, meaning the doors will not close fully with something between door and door seal. The only gasket material that should be used is flat gasket if necessary. When replacing any that was added, it is important to wire wheel all old gasket cement off door seal so it doesn’t build up any thickness. That will stop latch from tightening on the wedge.

The angle of left door handle is not movable. When latched, the right door handle should match the same angle. If not, heating the latch rod with a torch is how to adjust latch rod. Bending while hot allows the rod to be bent tighter to a 90* angle as they tend to straighten out when overtightened or door gasket is added. They bend easily cold with a big wrench or pipe, but will go back when heated, so they must be heated to adjust. A propane torch is enough to get it hot enough. I bend with a large adjustable wrench very easily.

Since your latch is loose, this should have been corrected first, door gasket removed and door seal wire wheel clean as well as the back of doors. Adjust latch, and see if gasket is necessary. It normally isn’t. They were built this way to alleviate the need for replacement of gasket material. So many others use gasketing that new owners think it is missing and mistakenly add it.
 

coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,667
NE PA
The manual you linked to is after 1980 with arched top doors. That model will have a UL Label on the rear shield, does not have angle iron corners that become legs. A picture of your stove would identify it quickly.

If it has flat top doors it is pre 1979 Series I.
If it has arched top doors they are Cathedral, and used on both UL Listed and old style unlisted models 1980 and after. Both were available in 1979 which is why a picture may be the best way. I can give you other information about it as well with good pics.

All manuals are here;
 

Frankferter

Member
Jan 28, 2017
2
Portland, OR
Your posts were so crazy helpful. Thank you very much! I appreciate the time you took to answer. I'm in the middle of getting it all back up to where it should be and so far everything is going well. I'll report back when it is all complete.