What fisher do i have?

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Brucek1$

Member
Nov 21, 2017
113
Cook mn
Trying to figure out what stove i have, by measurements it appears to be a goldilocks and it also sits on a pedastil but there are no holes in the pedistil to bolt it to the floor. The doors have air controls on each side and i dont see the air control that the manuel describes it having.and the flue out of the stove i beleive is 8 inch. 20171122_064209.jpg 20171122_064238.jpg 20171122_064209.jpg 20171122_064238.jpg
 

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Also forgot to mention that inside the back heat shield is what looks to be a loop of copper tubing that runs down into my crawl space, was wondering if that is part of the stove if i could remove it as i dont plan to use it, there is also bo UL labels on the stove
 
Teddy Bear
The water coil was added, not factory.
It uses Grandma doors and has "nickel shields" to protect the outer door plating.
They look identical to a Goldilocks which uses the pedestal as an air intake up through the floor for manufactured housing.
Manual is in the sticky section at top with other manuals.
It should have a 7 inch outlet.
 
The way the pipe was on it when i moved into the house was withe the pipe on the outside of flue outlet, im assuming it should go inside the stove instead, would i be alright to go with a 7x8 reducer right out of the stove to the 8 inch pipe i already have
 
Sorry, no manual, I was thinking Honey Bear.
Yes, connector pipe should be inside flue collar. Flue damper is required, it doesn't show in pics.
How much connector pipe to chimney, and any bends?
What type chimney? Masonry or insulated metal? Is it 8 inch flue to the top?
This is an efficient stove that must have 7 inch factory built insulated chimney (or best chimney for it is insulated 6 inch) all the way. Manual will require it for UL approval to be installed as tested. There may be a sticker / UL tag on pedestal that has been painted over. Increasing to 8 allows flue gasses to cool, slowing draft. This requires much more heat to be left up chimney, plus heating the additional square inch area inside flue to the top wastes a lot more heat. It needs to maintain 250* f. to the top of chimney. You will go through much less fuel with the proper chimney. There should also be a baffle plate inside the stove, on an angle below the outlet.
It can be used with doors open with fire screen in place for a Fireplace. You then need the flue damper to control fire.
The right side door handle needs adjustment, someone has been leaning on it to latch it too hard.
Only clean the door trim with metal polish for precious metals such as silver, gold, brass, nickel...... Never anything abrasive.
 
Here is the brochure;

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It's 8 inch all the way through the roof, its about a 5 ft run from top of stove to the ceiling support box then there is i think 3 mabie four sections of the class a piping through the roof.no bends it's a straight shot, i guess what im wondering is, is it safe to run it with the 7x8 reducer out of the stove and then keep my existing 8 inch pipe, and is the flue damper really necessary i never run it with the doors open, and do you usually screw through the collar on the stove into the single wall pipe
 
Two types of chimneys; Pack, which is double wall with 1 inch heavy packed insulation, so 8 inside is 10 out. Or triple wall which is the inner flue pipe with thin insulation wrap, a second wall, then another inch of air space to outer wall. They measure 6 inside and 10 out. Both are rated the same for safety.

Normally a double wall pipe rests on stove top and in the flue collar. Installation kits were supplied by Dura-Vent. Under support box was a telescoping adjustable section, so it wasn't going anywhere inside the collar between stove and ceiling box. That's why there are no holes in original flue collar. The reason it is advised to secure each single wall section with 3 screws including the stove collar, is due to pipe configuration with elbows that can tilt if something comes apart. When single pipe is used there is more heat loss through the pipe before the support box. You need 300* or more where it enters chimney with an insulated flue the same size. (when smoke is present) I don't recommend increasing at all. The installation instructions do not allow it. (shown on brochure as well) Expanding from 6 to 8 almost drops the temp in HALF. I never measured flue temps increasing one inch. But you will need considerably higher temp below ceiling box where it expands. In your case the pipe should be 7 inch and increase at chimney. This allows less heat loss with the smaller pipe and faster flow. A stove with larger capacity could take advantage of the larger pipe slowing flow to allow more heat loss through pipe. Yours needs no loss with preferably double wall pipe. It doesn't sound like much, but the square inch area of 7 inch is 38.5 square inches compared to 50.25 square inches inside the round 8 inch. Heat loss from that stove is not enough to keep the larger area hot enough to prevent creosote. That not only becomes the safety factor, but the stove will not have enough BTU to radiate outward to heat the rated heating space. You can see why, with a 6 inch chimney that is 28.25 square inches, that is almost 1/2 the size of your 8, requiring 1/2 the amount of heat you're leaving up. Then you use the flue damper to slow velocity, decreasing heat loss.
You're running a large cubic engine full throttle (wide open large chimney) with the engine in a small car designed for good fuel mileage. It's not the car using too much fuel (stove), it's the chimney (engine). The smaller the stove, the more critical the heat loss. A Baby Bear connected to your chimney couldn't heat the area it's in. It needs to leave too much up to keep itself going. Yours is approaching that and is why the manufacturer states 7 inch is required. A larger chimney only has the capacity for more flow when giving it more heat. It doesn't create more draft with the same amount of heat left up a smaller chimney.

You may not need a flue damper during normal operation since you need so much heat left up the chimney. The damper is a variable resistance that controls too much draft created by chimney. It affects the stove by slowing the air coming in. It is a chimney control, that affects the stove. You should have one as an emergency brake if something gets stuck loading and you can't close doors. This becomes your only control to slow the fire. Close until smoke forms at top and starts to roll in. Open slowly until smoke rises into stove. It also helps when starting a fire with kindling. When you hear a roar going up the chimney, slowly close until roar stops. This prevents too much heat from going up the chimney when you need it to heat larger pieces of wood in the firebox. That is not the time to close air intake to slow the fire depriving it of oxygen when starting. As it comes up to temp, open damper and close air inlets down to about 1 turn. Then adjust for heat output.
 
Makes sense to me, i think i have the adjustable section your talking about, mine has like 1/4 turn fitting like class a has that turns into the ceiling box and it is about 2 ft long, so your saying my best bet would be to run 7 inch right out of the stove to the ceiling box and put the reducer there, can i cut that adjustable section so the reducer is closer to the ceiling
 
I don't know what manufacture of pipe you have. You're using it as an increaser, correct? Increase at support box if the twist lock allows it. You probably have to use that lock device to connect to support box and decrease below that, using the special twist lock. You should be able to shorten the adjustable piece.

The larger the diameter of single wall pipe, (and flue) the slower the rising gasses inside and the more heat loss through the pipe, also due to increased surface area of pipe. So the cooler the flue gas will be where it enters chimney. You're chimney will be too cool as it expands, so keep it as hot as possible with the smaller 7 inch pipe or preferably double wall connector pipe which is used for close clearance or extreme ceiling height where too much single wall pipe allows flue gas to cool too much. Venting a stove horizontally through a wall into an exterior chimney also requires double wall pipe to keep the flue gas hotter since the outdoor chimney requires more heat. This becomes critical in the later Fisher Stoves with baffles since the baffle decreases the lost heat. Older stoves without baffles didn't have the requirement in installation instructions like the newer manuals with baffles for that type installation. That gives you an idea how much heat you need in the chimney. In your case that would get you much higher flue gas temps at the ceiling box with less loss through the single wall pipe. Not saying it would be enough to make it work correctly with 8 inch, but it would be much better staying cleaner.
 
The class a pipe is called pro jet its made by warnock hersey, and yes im using the 7x8 as an increaser, i burned last year and some this year with it and have never had any draft issues like smoke coming in or anything and ive cleaned it once after first moving in and it was clear as a whistle then and this fall when i cleaned it, i would think by running 7 inch up to the ceiling i should gain more draft correct? id love to just buy all new class a pipe in 7 inch and do it to specs but after you add up the cost of all new pipe support boxes and roof flashing i could almost just buy a new stove that will work with the 8 inch pipe.
 

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Warnock Hersey tests products, they don't manufacture anything.
Oliver MacLeod is the manufacturer.

No, connector pipe does not increase draft. It reduces it. The smaller the connector pipe, the more resistance. (heat loss from more surface area is more critical in your case than added resistance) Some basics are needed to understand what a chimney does and what it is for. It is not only to let the smoke out;

Heated exhaust gasses rise in the flue due to the differential temperature between inside and outside of chimney flue. This creates a low pressure area in the flue, pipe and stove, which is lowest at the stove collar. Atmospheric air pressure PUSHES into the stove at the air intake allowing oxygen to the fire. The chimney makes positive draft and everything else reduces draft. This is why the chimney is considered the engine that drives the stove. The more efficient the stove, the less heat you have to create the proper low pressure required by each stove. Below 250* f. water vapor condenses on the flue walls allowing smoke particles to stick. This is creosote which can form rapidly at lower temperatures. The smaller the flue, the faster the rising smoke particles which decreases the time they dwell in the chimney, reducing creosote. You're allowing enough heat up the stack to prevent this build up, but you're also wasting more heat and fuel than necessary to do this. Reducing from 7 to 6 at the stove and connecting to a 6 inch chimney is by far the most efficient and any newer stove can connect to the system.

Since the capacity of the 6 inch is less than the 7 or 8, the stove will not have the maximum BTU output wide open, but you never should need that kind of heat. Output vs. waste at cruise is your goal. (about 1/2 damper on a straight up system with 6 inch was found to be the best on my test chimney when I tested all the stoves adding baffles - I used a Goldilocks, not Teddy with base raised off floor for intake pressure. Yours should be the same, my chimney is 3 - 36 inch sections over 8 foot ceiling support box) No smoke roll in issues will be encountered with your system since the resistance of no elbows, extra pipe, etc. are in the system. (flue damper becomes a variable resistance) Your baffle plate is a resistance inside the firebox which is designed for reducing smoke particles while allowing the proper heat out for the smaller chimney. My goal was designing a baffle for the single door stoves based on the factory baffle in yours and later full size models. I raised the plate for the area above plate that exhaust travels to equal the exact flue cross section square inch. No smoke roll in was encountered and the 8 inch larger stoves worked very well reduced to 6 with the baffle adjusted for the smaller diameter. They were designed as well as yours with the larger outlet for open door burning.
Your baffle also should have 3 X 2 inch notches on the corners which is another reason you're not experiencing creosote which is more technical than you need to know......

You are probably running with the air intakes farther open to burn harder and require more frequent loading to keep your larger chimney hot and clean.
Do you have enough coals in the morning to start the fire without a match? The duration of a fire goes by how long it burns without needing a match to relight. You should experience 8 hour burns. You will notice much more heat output with the correct size chimney.
 
I've never burned over night with mine, typically we just run at from about 330 pm to around 9 at night, provides us enough heat for when our electric heat cuts out cause we are on duel fuel with electric and wood stove as back up, but id say once i get the stobe up to temp and go to load it again i get about a 3 hr burn with the air controls probaly open about 1 turn mabie a little more, and im burning jack pine
 
I think I'm gonna try running it with the 7 inch pipe to the support box and with the 8 inch through the roof this year, should burn the same if not a little better, i would change it out now but would be tough now cause we already have snow on the roof haha another question, up in my attic where the support box is is there suppose to be a shield around the pipe? It still has atleast the 2 inch clearances, i only ask cause i am thinkinh about blowing in about a foot of insulation in the attic but dont know if there should be something there now( rafters are 6in with only 6in of insulation) or if i just need a shield for the blow in. Thanks
 
Yes, the insulation guard prevents contact with chimney parts. It is sheet metal in a large coil shape with what looks like a large storm collar to close the top;

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Thanks for all the info, its been really helpful. I wanna keep this stove as they are built very well and the story behind them is great. Hoping the new stove pipe setup will work. If i understand correctly only issues ill run into is creosote build up and shorter burn times? Is there some kinda rough temps i could watch for on my temp gauge to tell how well its working
 
Pipe surface temps (single wall) should be about one half the stove top temperature when up to operating temperature. (with that baffled stove)