Jacksnipe

[Mattman]

I have a fisher insert I just purchased and wondering if I can get dimesions on your internal baffle. I would like to add this to my unit. Also can I get any information you have on you two fans I would like to add these as well.

Also do the two side air intakes and the front intake all work together?

 

[jacksnipe]

I have a fisher insert I just purchased and wondering if I can get dimesions on your internal baffle. I would like to add this to my unit. Also can I get any information you have on you two fans I would like to add these as well.

Also do the two side air intakes and the front intake all work together?

I only use the side air intake draft knobs when starting from a dead cold unit. When the insert top reaches around 450 degrees, I close the side draft knobs & only use the top air slides to operate the insert. When the insert top reaches 600 degrees, I shut down the top air slides & monitor the unit as needed.
The angle iron baffle frame I made is constructed of 1 1/2" x 1 1/2" x 1/4" 1020 hot rolled steel angle iron bolted together to accept two rows of 4 1/2 x 9 fire brick. The only thing I can tell you at the moment about the size is, the baffle is the full width the of firebox interior, when pushed to the rear is comes to within 2 1/2" of the door opening.
I have PDFs drawings of it somewhere where I have shared it with others.
When it comes to the blowers, I have what is probably the only existing PDFs copies of the original blower boxes for the left & right size. You will need a precision sheet metal shop to fabricated these up from the prints. The blowers is another topic. I could talk about this for hours from all the trial & error with design. It works pretty good & I would not run the insert without the baffle in place.

 

[Mattman]

I only use the side air intake draft knobs when starting from a dead cold unit. When the insert top reaches around 450 degrees, I close the side draft knobs & only use the top air slides to operate the insert. When the insert top reaches 600 degrees, I shut down the top air slides & monitor the unit as needed.
The angle iron baffle frame I made is constructed of 1 1/2" x 1 1/2" x 1/4" 1020 hot rolled steel angle iron bolted together to accept two rows of 4 1/2 x 9 fire brick. The only thing I can tell you at the moment about the size is, the baffle is the full width the of firebox interior, when pushed to the rear is comes to within 2 1/2" of the door opening.
I have PDFs drawings of it somewhere where I have shared it with others.
When it comes to the blowers, I have what is probably the only existing PDFs copies of the original blower boxes for the left & right size. You will need a precision sheet metal shop to fabricated these up from the prints. The blowers is another topic. I could talk about this for hours from all the trial & error with design. It works pretty good & I would not run the insert without the baffle in place.

Is it possible to get a copy of the drawings? Also do the side cold air intakes and the bottom intake in the front all blow out the top?

 

[Mattman]

So in other words if you blow air in the front will it also pull air in both sides and out the top altogether? Or if you blow air in both sides will it also pull air under the front and out the top together?

 

[coaly]

With no blower, the heated air rises out the top drawing from the front opening across bottom. Slots are added for side blowers left, right or both.
The side air inlets blow out the top, the same as the bottom does when they don't have side slots. Not all Inserts have side slots. Most use the bottom intake only.
The idea is taking the coolest air off the floor.
Here is thread showing the different styles of blowers that were available and some homemade ones;
https://www.hearth.com/talk/threads/made-a-blower-for-my-fisher-insert.117672/

 

[jacksnipe]

Is it possible to get a copy of the drawings? Also do the side cold air intakes and the bottom intake in the front all blow out the top?

Ok, I found the cad drawing of the baffle frame assembly that I designed for the fireplace insert. PM me your email address & I will forward it to you..

Ken

 

[Mattman]

Ok, I found the cad drawing of the baffle frame assembly that I designed for the fireplace insert. PM me your email address & I will forward it to you..

Ken

Are the Fisher stoves suppose to have gaskets on the doors?

 

[coaly]

Are the Fisher stoves suppose to have gaskets on the doors?

Only with glass. The door seal on solid doors is the channel iron that makes a 3 point contact making them air tight as built.
Series III glass doors and Honey Bear uses gasket in sealing channel, Series IV with glass uses gasket on door.

 

[Mattman]

Only with glass. The door seal on solid doors is the channel iron that makes a 3 point contact making them air tight as built.
Series III glass doors and Honey Bear uses gasket in sealing channel, Series IV with glass uses gasket on door.

Someone must have put a gasket on it before I purchased. The stove seems to struggle to get enough air. I'm burning the wood complete but I struggle to be up to 450 degrees?

 

[coaly]

450* stove top temperature?
Full size Insert ? Glass or solid doors?

Sounds like a draft issue; Is this connected directly to a liner?
If not, an air leak around face plate allows air up chimney by going AROUND firebox, not through it. ALL intake air going up chimney must go through Insert, through air intake and out exhaust vent to get to chimney flue.

Chimney; What type (masonry or pre-fab stainless)
1) Height
2) Flue diameter all the way up ? Clay or insulated liner?
3) Connector pipe length, and damper ?

No other openings into chimney or leaking clean out doors?

 

[Mattman]

Its a poured solid flue out of refactory cement. It was over $3000 to complete when it was done about 10 years ago. 9" round down to the flue above the damper. The damper door was taken out and the insert was put in and the face of the insert sealed off.

 

[Mattman]

Its a poured solid flue out of refactory cement. It was over $3000 to complete when it was done about 10 years ago. 9" round down to the flue above the damper. The damper door was taken out and the insert was put in and the face of the insert sealed off.

So the top of the Insert is not connected. It has to go 18-24" before it gets past the damper door.

 

[coaly]

Do you know your Insert model ? There are full size, Honey Bear, Cub Bear, and Polar Bear models with different heat outputs. All of them get hotter than 450* surface temp. The chimney size does make a difference for different models, so that is needed first.

Regardless, that is no longer an acceptable installation. (for many years, code has required direct connection to flue)

Inserts were made to slide into the hearth like yours is installed, and time has proven they create much more creosote using the larger flue designed for an open fireplace. Flue gasses expand and cool too much decreasing draft, allowing water vapor to condense, causing smoke particles to stick. Flue gasses must stay above 250* to the top during burn when smoke is present, and this temperature is also required to get air into the firebox. You don't loose enough heat out of a smaller exhaust opening and now have controlled air intake for controlled combustion compare to an open fireplace. It's all about having the right chimney for the stove. The chimney has to create the proper air pressure differential at the air intake to allow atmospheric air pressure to push into the stove. Without the proper hot expanded flue gasses rising out, you won't get the proper air flow in. Even velocity has a lot to do with the proper burn creating turbulence in the firebox (one reason for baffle plate) for a better mix of oxygen with flammable gasses exiting wood.

Does the Insert have a chain or lever controlled damper??

Has this been used for 10 years without removing Insert?

Your installation requires removal each time flue is cleaned to remove soot and creosote that falls behind Insert. That is another benefit from direct connection to liner. Debris falls into Insert fro removal. Plus the seal around face plate no longer is an issue leaking air into flue around Insert. These are the reasons other than the code change requiring direct connection.

Double door stoves and the full size Insert was designed with 8 inch outlet due to using larger existing fireplace flues. (letting more heat up to keep larger area hot) For open door operation with screen in place (without glass) in case of less than optimal chimney, they were designed to prevent smoke roll in with larger outlet.
With insulated flues decreased to 6 inch inside, it has been proven even the full size Insert drafts well, are much more efficient, and do not smoke when opened, even adding a baffle plate. It is technically against code to reduce the flue size smaller than any stove outlet. This is to prevent choking a stove that requires the flue to be no smaller than the stove outlet normally sized to the firebox size. The double door stove firebox is no larger than a Papa Bear firebox with 6 inch outlet, they were only made oversize for open door burning and fireplace chimneys. Unfortunately the code doesn't take that into account.

Your heat is being used to heat masonry and a space 63.58 square inches across all the way up. (Need chimney height for complete calculation, it's more complicated than diameter only)
A 6 inch liner only requires enough heat to keep 28.26 square inches above 250* to the top. You can see what a wrap of insulation around liner does to be able to reduce heat lost up chimney, allowing appliance to heat up, instead of chimney. The smaller the stove, and the more efficient the stove, the more critical this becomes since you no longer have heat to loose up the chimney. You can't baffle your Insert decreasing heat loss with your current chimney flue.

 

[Mattman]

This was resentfully put in. I plan to modify the damper door and connect the 7 inch round from the top of the stove to the damper door. At this point it will be in the poured refractory chimney all the way to the roof. This is the older ranch style house with the basement I would estimate 18 to 20 feet of chimney. The chimney is 9 inch round solid poor. The diameter of the pipe coming off the stove is not 8 inch it's more like 7 1/2. Once I'm past the damper door it's sealed to the chimney the rest of the way up I don't want to do anymore to modify or put any more money into the chimney I put $3000 into the poured one I have. This may not be ideal but it'll give me sealed from the fireplace above the damper door and should greatly improve the draft in the combustion.
Thoughts??

 

[coaly]

Are you using the damper that came with the Insert? It will be chain or lever type on the right side of insert extending through the face plate.
If there is no damper built into the top of it, that is another reason your heat output is low.

Close to 7 1/2 ID is normal for 8 inch OD pipe.

When you say the face plate has been sealed to the hearth front, it needs to be air tight so no air can leak around the Insert. I'm not sure if you have that. That is the #1 reason for not getting air into the firebox.

The reason I asked if this has been used for 10 years without removing insert, is the possibility of debris from cleaning filling the area behind it and closing off outlet.
Your old fireplace damper should not need to be used and a block off plate should close the space around connector pipe extending up into flue.
Then any air leak around Insert will be avoided. It will not draw as well as an insulated liner, but it will alleviate any air leaks into flue.

Are there any other openings into flue or clean out doors? Any leak into flue will prevent stove from coming up to temperature.

I hope you meant you resent the chimney, not installing the Fisher Insert. It will work better than a newer Insert that won't work with your larger 9 inch flue at all. A newer Insert will require a new 6 inch liner all the way.

This is what the top of your insert should look like.

 

[Mattman]

I have been leaving the damper wide open. Its the flat bar type that comes through the face plate. It has notches in it. How far should I close it down once the fire is hot? The faceplate was sealed with fire rated fiberglass insulation. Your photos are just what I have. There are no other openings. One other issue is that I may need better wood. I dealing with dry slab wood and alot of somewhat green wood. I have attached a you tube link that shouws what was done to my chimney. The chimney was done about 10 years ago but all we ever had was just the standard fireplace and would burn once in a while in the winter. The chimney and fireplace was spotless clean when we put in the Fisher this year.

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[coaly]

See what temperature you get with a load of seasoned wood first.

If stove top goes to 600 or more with intakes open a turn to a turn and a half, close damper half way. That's what I expect it to do. With a stove, you can get to the pipe where it enters chimney to check temperature. You then allow for cooling to the top and run where you believe it will stay above 250* to the top. An insulated 6 inch flue may require 300* surface temperature (internal flue gas temperature is normally 30 to 50% higher) where your larger uninsulated flue may require twice that. Checking for creosote formation near the top regularly will show if you're running hot enough.
The damper is a variable resistance that slows velocity of flue gasses affecting air flow into stove. As long as your problem is fuel, and not an air leak around Insert, it should roar with small splits or kindling with damper open and draft caps open 2 or more turns. Closing the damper to where the roar stops gives you an idea where you will be running damper. One turn each is normal operation or a little more or less for heat desired. Damper setting will vary with weather conditions and fuel. You're burning correctly when you have a pile of coals in the back in the morning.

For open door operation with screen, slowly close damper until you see smoke start to roll in at top. Open slightly to prevent smoke inside. This becomes your only control during open door burning with screen in place. It is not considered a radiant heater in Fireplace Mode.