I recently purchased a house in Virginia that has a 1980 model year Fisher Grandpa Bear III Stove (UL listed) in the basement. The home inspector I used said that it was "missing the fiberglass seal to prevent the exit of Carbon Monoxide" that would have to be replaced before it could be used. In reading through the forums here I see nothing about these Fisher stoves having any kind of seal on the doors. I've read a number of stories here as well of folks buying and restoring these older Fisher stoves and this was never mentioned as something that was done. I have not used it yet and probably won't need to until next winter but I'd like to have it be ready to use by then. The previous owners said that they only use it a couple of times because it was "quite smokey." I don't know if that is a result of this "missing seal" or if that is just the norm for these older stoves. It otherwise seems to be in good shape. Is there a seal for these stoves and if so where do I get one?
FISHER Door Gasket Question
- Thread starter SmokeMonkey
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No gasket material is used on any Fisher Stove with solid cast iron doors. There is no clearance space between the door and stove face for gasket material.
Only Glass door models use gasket.
The door seal is the 1 inch channel iron welded on stove front. The doors make contact in 3 places all the way around the doors making it "air tight" as built. You won't find any door seal pictures or information in owners manual.
Most stoves required gasket material and one benefit of buying a Fisher is the lack of the need to maintain the door gasket material. So many people mistakenly added door gasket material to them causing the doors to not close properly.
You could always apply the thinnest gasket material you can find at any hardware store that is the flat type for glass installation. The doors should still close with that type. It comes off a roll like rope sold by the foot. You apply it with Rutland Stove and Gasket Cement. Door gasket material for other stoves is normally round and too thick to allow your doors to close properly.
In your case you could apply the gasket material with a little Elmers glue and close doors to allow to dry in place. Unfortunately it's easier to do this than to try to teach an inspector something. Remove it before use.
If this 'inspector" knew anything about the physical operation of a heating appliance connected to a chimney, he or she would know the rising gasses in the chimney are lighter than outside air which causes a LOW pressure area in chimney, connector pipe and stove. (This is measured as draft) This LOW pressure area is what allows the HIGHER atmospheric air pressure to PUSH INTO the stove intake feeding the fire oxygen. The chimney is the engine that makes the stove work! So any air leaks at pipe joints or chimney allows cooler outside air INTO flue cooling the flue reducing draft.
A leak in the stove or door seal allows higher pressure indoor air INTO stove making it burn faster. Smoke doesn't leak OUT, air leaks IN. Crack the doors when in operation and watch the fire rise from air trying to get into chimney to equalize the pressure.
(You can always ask him what kind of seal he requires on a fireplace to prevent CO from leaking in
. Your stove also came with a screen for open door operation which indoor air pressure rushes into stove and up chimney preventing smoke and combustion gasses from entering building. It is NOT considered a radiant heater in Fireplace Mode).
My favorite saying is "Those who can't do, teach. And those who can't teach , inspect".
Only Glass door models use gasket.
The door seal is the 1 inch channel iron welded on stove front. The doors make contact in 3 places all the way around the doors making it "air tight" as built. You won't find any door seal pictures or information in owners manual.
Most stoves required gasket material and one benefit of buying a Fisher is the lack of the need to maintain the door gasket material. So many people mistakenly added door gasket material to them causing the doors to not close properly.
You could always apply the thinnest gasket material you can find at any hardware store that is the flat type for glass installation. The doors should still close with that type. It comes off a roll like rope sold by the foot. You apply it with Rutland Stove and Gasket Cement. Door gasket material for other stoves is normally round and too thick to allow your doors to close properly.
In your case you could apply the gasket material with a little Elmers glue and close doors to allow to dry in place. Unfortunately it's easier to do this than to try to teach an inspector something. Remove it before use.
If this 'inspector" knew anything about the physical operation of a heating appliance connected to a chimney, he or she would know the rising gasses in the chimney are lighter than outside air which causes a LOW pressure area in chimney, connector pipe and stove. (This is measured as draft) This LOW pressure area is what allows the HIGHER atmospheric air pressure to PUSH INTO the stove intake feeding the fire oxygen. The chimney is the engine that makes the stove work! So any air leaks at pipe joints or chimney allows cooler outside air INTO flue cooling the flue reducing draft.
A leak in the stove or door seal allows higher pressure indoor air INTO stove making it burn faster. Smoke doesn't leak OUT, air leaks IN. Crack the doors when in operation and watch the fire rise from air trying to get into chimney to equalize the pressure.
(You can always ask him what kind of seal he requires on a fireplace to prevent CO from leaking in
. Your stove also came with a screen for open door operation which indoor air pressure rushes into stove and up chimney preventing smoke and combustion gasses from entering building. It is NOT considered a radiant heater in Fireplace Mode).My favorite saying is "Those who can't do, teach. And those who can't teach , inspect".
Thank you Coaly. I'm pretty much a novice with wood burning stoves having only ever lived in more temperate climates in Southern CA and Central FL so I appreciate all of this good information. The chimney was cleaned and a new flue tile liner was installed by the previous owners so hopefully that helps with the smoke issues they say they were experiencing. I guess I'll give it a test run and see how it goes. Also, the owners manual says to always leave 1" of ash on the firebox bottom. What is the reason for that?No gasket material is used on any Fisher Stove with solid cast iron doors. There is no clearance space between the door and stove face for gasket material.
Only Glass door models use gasket.
The door seal is the 1 inch channel iron welded on stove front. The doors make contact in 3 places all the way around the doors making it "air tight" as built. You won't find any door seal pictures or information in owners manual.
Most stoves required gasket material and one benefit of buying a Fisher is the lack of the need to maintain the door gasket material. So many people mistakenly added door gasket material to them causing the doors to not close properly.
You could always apply the thinnest gasket material you can find at any hardware store that is the flat type for glass installation. The doors should still close with that type. It comes off a roll like rope sold by the foot. You apply it with Rutland Stove and Gasket Cement. Door gasket material for other stoves is normally round and too thick to allow your doors to close properly.
In your case you could apply the gasket material with a little Elmers glue and close doors to allow to dry in place. Unfortunately it's easier to do this than to try to teach an inspector something. Remove it before use.
If this 'inspector" knew anything about the physical operation of a heating appliance connected to a chimney, he or she would know the rising gasses in the chimney are lighter than outside air which causes a LOW pressure area in chimney, connector pipe and stove. (This is measured as draft) This LOW pressure area is what allows the HIGHER atmospheric air pressure to PUSH INTO the stove intake feeding the fire oxygen. The chimney is the engine that makes the stove work! So any air leaks at pipe joints or chimney allows cooler outside air INTO flue cooling the flue reducing draft.
A leak in the stove or door seal allows higher pressure indoor air INTO stove making it burn faster. Smoke doesn't leak OUT, air leaks IN. Crack the doors when in operation and watch the fire rise from air trying to get into chimney to equalize the pressure.
(You can always ask him what kind of seal he requires on a fireplace to prevent CO from leaking in
My favorite saying is "Those who can't do, teach. And those who can't teach , inspect".
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As far as excessive smoke;
Your Grandma III had a baffle installed in firebox called a "Smoke Shelf Baffle" designed to reduce smoke which is unburned particles.
Raising firebox temperature by operating with more intake air and proper fuel (seasoning) will eliminate most smoke problems.
The reason for burning on an inch of ash is to reduce the air from getting to the fuel and the coals will last much longer extending the burn time.
Burn time is considered from when lit, to when it will no longer light a new fire without a match. So it doesn't have much to do with heat output in the last few hours. Some people mistakenly use a fireplace grate in a stove which raises the wood and allows more air flow through it for fast burning. This was needed in a fireplace where you have a much larger flue requiring much more heat to keep it drafting and prevent creosote in the flue. Don't pack the logs so tight they don't get oxygen between them, you'll learn different ways of loading for different heating needs.
If you need to burn 24/7, you will find you need to allow the fire to die to remove ash. To prevent this, you'll find it will burn down to fine ash at the front behind the air intakes overnight. Depending on how much air it was given all night, you should have charcoal and glowing coals towards the back. Each morning, remove ash down to 1 inch in the front, then rake ahead the coal pile with a little ash from the rear. Kindle a new fire on the coal bed and it should take right off. This allows constant burning without letting the fire die to clean the ash. ALWAYS put ash in a metal container outside on bare earth. Never inside or on a deck !
The flue size should be the same as the outlet on the stove which is 8 inch round. Diameter all the way up is critical to be able to keep the flue above 250* to the top or water vapor from combustion will condense on flue walls allowing smoke particles to stick. This is creosote. A larger than necessary flue allows flue gasses to cool as they expand, so you then need to allow much more heat up the stack to keep the inner flue temps above the critical 250*f. That is the main reason for insulated flue liners, to be able to keep the flue hotter allowing less wasted heat up the chimney, increasing efficiency.
Your Grandma III had a baffle installed in firebox called a "Smoke Shelf Baffle" designed to reduce smoke which is unburned particles.
Raising firebox temperature by operating with more intake air and proper fuel (seasoning) will eliminate most smoke problems.
The reason for burning on an inch of ash is to reduce the air from getting to the fuel and the coals will last much longer extending the burn time.
Burn time is considered from when lit, to when it will no longer light a new fire without a match. So it doesn't have much to do with heat output in the last few hours. Some people mistakenly use a fireplace grate in a stove which raises the wood and allows more air flow through it for fast burning. This was needed in a fireplace where you have a much larger flue requiring much more heat to keep it drafting and prevent creosote in the flue. Don't pack the logs so tight they don't get oxygen between them, you'll learn different ways of loading for different heating needs.
If you need to burn 24/7, you will find you need to allow the fire to die to remove ash. To prevent this, you'll find it will burn down to fine ash at the front behind the air intakes overnight. Depending on how much air it was given all night, you should have charcoal and glowing coals towards the back. Each morning, remove ash down to 1 inch in the front, then rake ahead the coal pile with a little ash from the rear. Kindle a new fire on the coal bed and it should take right off. This allows constant burning without letting the fire die to clean the ash. ALWAYS put ash in a metal container outside on bare earth. Never inside or on a deck !
The flue size should be the same as the outlet on the stove which is 8 inch round. Diameter all the way up is critical to be able to keep the flue above 250* to the top or water vapor from combustion will condense on flue walls allowing smoke particles to stick. This is creosote. A larger than necessary flue allows flue gasses to cool as they expand, so you then need to allow much more heat up the stack to keep the inner flue temps above the critical 250*f. That is the main reason for insulated flue liners, to be able to keep the flue hotter allowing less wasted heat up the chimney, increasing efficiency.
Also, in order to test a stove and chimney, it is very difficult during warm weather. The reason is the low pressure area needed in the stove for air to get to the fire depends on chimney draft. This depends on temperature differential between inside and outside of flue. The larger the temperature differential, the stronger the draft, so more air moves into stove. The colder it gets outside, the stronger the draft, and the harder the stove will burn radiating more heat. So testing a stove on a 60* day will want to smoke inside and not work nearly as well as 40* or below. Starting a stove during warm weather you may need to light a wadded up piece of newspaper near the exhaust outlet to warm the chimney to start the draft. Opening a window close to the stove helps get the higher air pressure into the stove easier if you have a tight house. Remember, higher outdoor air pressure has to push through every crack to get into the lower pressure area created by chimney. Any exhaust fans in the building can over power the natural rising draft causing smoking issues into the building as well. The open window eliminates any negative pressure from clothes dryers or or other exhausting equipment in the building. When it gets down to the single digits you'll find most stoves start working like an entirely different stove with much better draft. For this reason you don't need to open the air adjustment too much more since it will naturally get more oxygen to the fire as the colder it gets.
Your stove operation is normally with air intakes, called draft dampers open a few turns to start. As it gets going, close them down to about 1 1/2 turns. As larger wood is put on, 1 turn should continue to get it going until established when you can close them down to the desired heat output. Usually 1/4 turn to 1/2 overnight and up to 1 turn when more heat is required. Every stove installation is different depending on chimney and connector pipe configuration as well as temperature and atmospheric conditions. (pressure varies from lows and highs moving over the intakes) For example, if you had a chimney flue twice the size as stove outlet, you may need two full turns open to allow it to burn fast enough to heat the much larger chimney. Fuel makes a huge difference in air adjustment as well which is why there is no exact air adjustment given.
Your stove operation is normally with air intakes, called draft dampers open a few turns to start. As it gets going, close them down to about 1 1/2 turns. As larger wood is put on, 1 turn should continue to get it going until established when you can close them down to the desired heat output. Usually 1/4 turn to 1/2 overnight and up to 1 turn when more heat is required. Every stove installation is different depending on chimney and connector pipe configuration as well as temperature and atmospheric conditions. (pressure varies from lows and highs moving over the intakes) For example, if you had a chimney flue twice the size as stove outlet, you may need two full turns open to allow it to burn fast enough to heat the much larger chimney. Fuel makes a huge difference in air adjustment as well which is why there is no exact air adjustment given.
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