Fisher Grandma Stove Pipe Connection Help Needed

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RANDYK

New Member
Aug 3, 2015
5
Oregon
Have a 1975 Fisher Grandma with 6" OD connection. During remodel have replaced the chimney and ceiling box. The ceiling box is a new installed Selkirk 206424 . For stove pipe am using new single wall ICC 6" Ultra Black sections with a slip length . The only way the pipe fits on the stove and the ceiling box connection is with the stove pipe male ends pointing up. I am burning the stove this way currently. I understand this is not correct. I am trying to identify the correct adapters for the stove and ceiling box to make a correct installation with male ends pointing down all the way from the box connection to the stove connection.

I should mention , the old pipe and box (1975 install) was also installed incorrectly with males pointing up , burned 5 cords / year for 25 years , kept the pipe clean , and never had an issue with this bad configuration . Do I really need to pursue a correct pipe installation ?
 
Double door stoves didn't exist until 1976 and have an 8 inch outlet. So there is no such thing as a 1975 Grandma.

Over-crimping of male end with hand crimpers is normally done at stove connection to install inside the flue collar. As you go around it crimping down smaller, pry outward with the crimp tool so it doesn't create a funnel shape at the crimped end.
Side or rear vented stoves can be connected with a drip tee OVER the flue collar and capped on the bottom to evaporate condensate. This allows the correct configuration at joints. Each joint must have 3 screws as well.

The first steel plate stoves used 6 inch OUTSIDE pipe that was a tight fit for connector pipe to fit into. Later stoves had a thicker wall 6 inch INSIDE pipe made for installation of connector pipe. It should be installed with all male ends down to prevent any condensed water vapor from leaking out. Operated correctly with insulated chimney this is rarely a problem.
Here is a current thread about the same issue and how much water vapor is actually produced.
https://www.hearth.com/talk/threads/reversed-flue-collar-creosote-leak.150046/#post-2013818
 
Double door stoves didn't exist until 1976 and have an 8 inch outlet. So there is no such thing as a 1975 Grandma.

Over-crimping of male end with hand crimpers is normally done at stove connection to install inside the flue collar. As you go around it crimping down smaller, pry outward with the crimp tool so it doesn't create a funnel shape at the crimped end.
Side or rear vented stoves can be connected with a drip tee OVER the flue collar and capped on the bottom to evaporate condensate. This allows the correct configuration at joints. Each joint must have 3 screws as well.

The first steel plate stoves used 6 inch OUTSIDE pipe that was a tight fit for connector pipe to fit into. Later stoves had a thicker wall 6 inch INSIDE pipe made for installation of connector pipe. It should be installed with all male ends down to prevent any condensed water vapor from leaking out. Operated correctly with insulated chimney this is rarely a problem.
Here is a current thread about the same issue and how much water vapor is actually produced.
https://www.hearth.com/talk/threads/reversed-flue-collar-creosote-leak.150046/#post-2013818

Thanks for the reply, Yes , bad typing , it is a 1976 double door , and , does have a 6" OD top outlet . The family that created these stoves lived a mile away from our home. I need to know how to correctly connect at the ceiling box , the male end fits nicely in the wrong orientation .


[Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed [Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed[Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed


[Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed
 
Must have been a customer who needed it for a 6 inch chimney or Bob tuned it up to work better than the normal 8 inch outlet used on the double door stoves. The square inch firebox area is smaller than the single door Papa Bear with 6 inch and many people reduce to 6 with no problem. Spotted Owl on the Forum is one of your old neighbors that moved away (Washington coast I believe) and has dibs on the first double door made with steel plate doors !
You can install male end down by crimping the end that fits into stove smaller and use the correct adapter at the ceiling box. I believe they snap in and don't remove easily. Or use it as is. The first original manual written by the PA fabricator gives these suggestions;

Pipe Direction
The crimped or smaller diameter end is called the male end and is inserted into the larger diameter size of pipe section.
Male end up installation;
Pro; This is the way most pipe installations are made and are easy to install.
Con; There may be leakage of creosote or condensation around the connections.

Male end down installation;
Pro; This directs creosote or condensation back into the stove and is consumed.
Con; The installation may require a special adapter converting inside diameter to outside diameter at the stove or at the connection between the chimney connector and the chimney.

Not much has changed over the years! When people close a damper too much or have a large uninsulated chimney that cools too much, water vapor condenses. You probably never experienced it. The gooey tar like liquid is not something you want leaking onto a hot stove top either.
Dura-Vent makes a double slip connector that works good at the stove. For the price of adapters, I bought a pair of hand crimpers to make the pipe fit and have them for whenever pipe is cut.
 
Must have been a customer who needed it for a 6 inch chimney or Bob tuned it up to work better than the normal 8 inch outlet used on the double door stoves. The square inch firebox area is smaller than the single door Papa Bear with 6 inch and many people reduce to 6 with no problem. Spotted Owl on the Forum is one of your old neighbors that moved away (Washington coast I believe) and has dibs on the first double door made with steel plate doors !
You can install male end down by crimping the end that fits into stove smaller and use the correct adapter at the ceiling box. I believe they snap in and don't remove easily. Or use it as is. The first original manual written by the PA fabricator gives these suggestions;

Pipe Direction
The crimped or smaller diameter end is called the male end and is inserted into the larger diameter size of pipe section.
Male end up installation;
Pro; This is the way most pipe installations are made and are easy to install.
Con; There may be leakage of creosote or condensation around the connections.

Male end down installation;
Pro; This directs creosote or condensation back into the stove and is consumed.
Con; The installation may require a special adapter converting inside diameter to outside diameter at the stove or at the connection between the chimney connector and the chimney.

Not much has changed over the years! When people close a damper too much or have a large uninsulated chimney that cools too much, water vapor condenses. You probably never experienced it. The gooey tar like liquid is not something you want leaking onto a hot stove top either.
Dura-Vent makes a double slip connector that works good at the stove. For the price of adapters, I bought a pair of hand crimpers to make the pipe fit and have them for whenever pipe is cut.


Thank you for the comments , right now , we are enjoying a reconnected stove after an extensive home remodel. Given our history with the chimney system and what the fabricator notes indicate , this is not a huge safety issue unless you let your pipe get out of hand . I burn dry Oak and regularly brush out the pipe 4 time each season. If anything, a little soot leaked out of the upside down joints when I brushed the pipe in the past on the old pipe.

thanks again.
 
It's also more of a concern when you have adjustable els that leak between movable sections and horizontal joints. Your only concern is the stove top and that is the hottest part where it evaporates inside. When someone has an 8 inch flue above the 6 inch pipe, it cools where it expands, condenses and drops back down.
Yours is the first fireplace Series stove I've seen with 6 inch. Not surprising since it probably came from Springfield. Any numbers or initials welded on the bottom? FSSO was the original from Springfield before the larger facility in Eugene.

One of the welders from GA built a Grandma width and Papa Bear depth he called the "Great Grandma" and used 6 inch for the outlet. Too bad they weren't all made with 6, but back then most were installed into existing fireplaces with even larger flues so they used the larger 8 inch outlet to prevent smoke roll in with less than optimal chimneys. He knew what chimney this one was being vented into and built it to trade the owner for the first stove built in Georgia.

[Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed [Hearth.com] Fisher Grandma Stove Pipe Connection Help Needed
 
It's also more of a concern when you have adjustable els that leak between movable sections and horizontal joints. Your only concern is the stove top and that is the hottest part where it evaporates inside. When someone has an 8 inch flue above the 6 inch pipe, it cools where it expands, condenses and drops back down.
Yours is the first fireplace Series stove I've seen with 6 inch. Not surprising since it probably came from Springfield. Any numbers or initials welded on the bottom? FSSO was the original from Springfield before the larger facility in Eugene.

One of the welders from GA built a Grandma width and Papa Bear depth he called the "Great Grandma" and used 6 inch for the outlet. Too bad they weren't all made with 6, but back then most were installed into existing fireplaces with even larger flues so they used the larger 8 inch outlet to prevent smoke roll in with less than optimal chimneys. He knew what chimney this one was being vented into and built it to trade the owner for the first stove built in Georgia.

View attachment 168382 View attachment 168383
There are no markings I could find on the stove when I refurbished it this last summer. . I have the original paperwork , which has a story starting in rural Cornelius , Oregon , where we live. Bob learned his welding skills on the farm there. I would bet our homes previous owner got this stove from them directly or at a local shop. The bear claw feet were carved by a fellow I met here online from Shropshire England and cast in the historical Ironbridge foundry . They were less expensive than the ones I saw on E bay . And neat story to go along with them. I did not like the chrome balls for my installation.
 
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