When I bought our home. The glass panels in the doors of the stove were covered in creosote (you could not see the burning flame at all). I bought some creosote glass cleaner and got close to 90% of the creosote off the glass. Figured it would solve the issue. But after two burns the glass is covered in creosote again and once again can’t see through the glass. Is this a glass issue? Would I need to replace the glass? Or does someone have any insight onto why the glass is getting a buildup.(I do run the stove at a plenty hot temp). Thanks. Any input would be appreciated.
Stove glass
- Thread starter Bucher86
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How dry is your wood? Wet wood or burning the stove too cool is probably the reason for the buildup.
A hot fire should burn off most of the black creosote. You still need to wipe the glass periodically to remove ash, which I do with a wet paper towel.
A hot fire should burn off most of the black creosote. You still need to wipe the glass periodically to remove ash, which I do with a wet paper towel.
Burn it Hotter. Do not wipe with Wet Towel if HOT! You never can keep the glass clean. Is it getting enough Air? Do you damp it down a lot?
The wood I’m burning is dry and I’m running the stove at around 600 surface temp. After I cleaned it. It turned black almost immediately after the fire started. On the first burn. By the second burn you couldn’t see through the glass at all.
I don’t damp the stove down much till I get a good bed of coals going. I’m running the stove plenty hot. I run the stove between 600-700 surface temp on the stove.
My first few years we could't burn without blacking the glass. I cleaned it every weekend. Hotter during the peak of the fire helped but as it cooled the glass would blacken so thick you couldn't see the fire.
Now I don't pay much attention and the glass is perfectly clear. Occasionally a little white haze. It wipes off with a wet paper towel. Amazing, same stove, same oak. Whats different is 3-4 year seasoned covered wood. Coals are fine, but my wife can still get a smoldering log that will do a little blacking.
Now I don't pay much attention and the glass is perfectly clear. Occasionally a little white haze. It wipes off with a wet paper towel. Amazing, same stove, same oak. Whats different is 3-4 year seasoned covered wood. Coals are fine, but my wife can still get a smoldering log that will do a little blacking.
What do you mean when you say it's dry? Can you describe how you dried the wood? I bet it's not as dry as you think it is.
Yea. Pretty much sums up my stove. Maybe the wood is still just a little wet. I’ll have to pay attention too it next year as my wood seasons and dries out more
Yeah your glass will probably never stay clean with that stove. Very few old stoves did
Lousy airwash if there is any at all. Windows on these old stoves like the Defiant etc. were almost useless.
It can be one of two things:
1. Lack of properly dried wood.
2. Most likely a stove design issue, especially if wood is below 18% moisture.
1. Lack of properly dried wood.
2. Most likely a stove design issue, especially if wood is below 18% moisture.
MongoMongoson
Feeling the Heat
We have a Quaker Stag at our cabin. The glass is never actually clean... but almost never black. It is normally very hazy, and provides a nice fire glow and flicker. We burn mostly dry sugar maple, ironwood, and popple in it...
I don't know about the Moravian, but the Stag has a sliding baffle. Slide it towards the door to start a fire, and the smoke can go straight up the stack. Once the fire is going hot, slide it back and the smoke/flames must come forward past the door and glass.
If I start a fire with the baffle to the back, the glass gets dark pretty quickly. If I don't move the baffle until the smoke and door are good and hot, the glass stays "clean".
I don't know about the Moravian, but the Stag has a sliding baffle. Slide it towards the door to start a fire, and the smoke can go straight up the stack. Once the fire is going hot, slide it back and the smoke/flames must come forward past the door and glass.
If I start a fire with the baffle to the back, the glass gets dark pretty quickly. If I don't move the baffle until the smoke and door are good and hot, the glass stays "clean".
You should post a picture of the stove so we know what model it is.
They made the arched top Moravian in an Insert, freestanding parlor and hybrid. (the hybrid has a round secondary intake at the top, front and center. Keep that closed for wood)
If it has grates (like flat plates on the bottom and a shaker handle on the right side) and a ash pan, it gets air through the ash pan door and is a hybrid wood/coal stove. They don't have the air wash the wood models have. Some models have a tag on the back with model number. They say wood, or wood/coal.
The wood stove models have slots through the doors under the glass windows. Is that the only air intake on your stove? Or are the air openings on the face plate below the doors?
Make sure there are no leaks into the stove. You want ALL incoming air to go through the air wash. Any leaks, like door gaskets or cracked cement in joints is air that balances the air pressure in the stove, taking away from what needs to rush into the intake at glass.
You don't have a fan blowing on the stove or across the front do you? Air movement over the glass can cool it causing problems.
Finally make sure the baffle is intact in the stove. Most had one in the top and directs heat forward.
The glass needs to stay hot. When starting it you may see condensation on the glass when first cleaned. If it fogs and takes a long time to dry off the smoke particles will stick. This is normal when cold. Water vapor is formed from burning the hydrogen in the fuel. Keep as much space as possible between logs to get air flow between them when starting it. Burn splits only, and keep the air wash intakes open until you need to adjust them closed more to slow it down for the needed output. If it gets dirty when first started many clean themselves by flaking off the glass after they get hot.
Are you using a stove pipe damper? You could be over using one. This will slow the air coming into the stove since it slows the velocity of rising gases up the stack. You want high velocity air coming into the air wash keeping smoke particles away from the glass. Make sure there are no deflectors or air guides missing or burned away. Some stoves have something to direct the air over the glass. If anything is missing the air goes straight toward the fire and up the stack instead of across glass where it needs to go. This is a part of good stove design, some are worse than others.
Does it get dirty near the top and stay cleaner at the bottom of glass? Or is the entire glass the same?
When they get bad I prefer the foaming oven cleaner. Let it soak until dry and recoat, scrape with razor blade.
I usually run the air wide open till it gets going real hot. Then I close the air intake and dampen it down about half way. I’m not expecting the glass to stay super clear.(it’s dark top to bottom) But I would at least like to be able to see into the stove while it’s burning. I may just have wet wood like a lot of people are saying. I tested for moisture and most of my ash was reading around 18% moisture. I will have to see next season if the glass gets this way again after my wood seasons another year.
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That is a wood burning Fireplace Insert, not stove.
That changes what is needed to work properly and be safe.
Did you check to see how it's vented?
Make sure this is connected to a liner the same size as the Insert outlet.
That is code and needs to be directly connected to the liner from Insert all the way up.
The safety reason is due to allowing exhaust gases to expand in a larger chimney flue that was existing for the fireplace. This allows them to cool below the critical 250* f. temp wetting the flue walls and allowing smoke particles to stick. This forms creosote. At one time you could do that, but time has proven they do not stay hot enough due to cooling of the exhaust gases.
Another reason is if the chimney does not comply with all current building requirements it needs an insulated liner. Indoor chimneys require 2 inches clearance to framing and exterior chimneys require 1 inch to combustible framing materials. Most do not comply and require an insulated liner.
The third reason is as I stated above, ALL air must go through the air wash intake. This is to get the correct flow across glass. It is difficult to seal an Insert to the face of a fireplace to prevent air leakage into the flue. This takes away from the air needed to go into the air intake across glass. Atmospheric air pressure will PUSH into any opening it can to get into the low pressure area caused by the chimney. That's what makes a stove go, and you want it all going through the air wash intake to keep smoke away from glass.
So if you never pulled the faceplate to check above the Insert, or don't know if there is a liner, check that first.
That changes what is needed to work properly and be safe.
Did you check to see how it's vented?
Make sure this is connected to a liner the same size as the Insert outlet.
That is code and needs to be directly connected to the liner from Insert all the way up.
The safety reason is due to allowing exhaust gases to expand in a larger chimney flue that was existing for the fireplace. This allows them to cool below the critical 250* f. temp wetting the flue walls and allowing smoke particles to stick. This forms creosote. At one time you could do that, but time has proven they do not stay hot enough due to cooling of the exhaust gases.
Another reason is if the chimney does not comply with all current building requirements it needs an insulated liner. Indoor chimneys require 2 inches clearance to framing and exterior chimneys require 1 inch to combustible framing materials. Most do not comply and require an insulated liner.
The third reason is as I stated above, ALL air must go through the air wash intake. This is to get the correct flow across glass. It is difficult to seal an Insert to the face of a fireplace to prevent air leakage into the flue. This takes away from the air needed to go into the air intake across glass. Atmospheric air pressure will PUSH into any opening it can to get into the low pressure area caused by the chimney. That's what makes a stove go, and you want it all going through the air wash intake to keep smoke away from glass.
So if you never pulled the faceplate to check above the Insert, or don't know if there is a liner, check that first.
There is a brand new liner that was installed before the owners sold the house. All paper work was provided. It was done by a reputable installer. So I’m not too concerned with the installation of the liner. But I may pull the faceplate and check to make sure everything was installed properly. Thanks for the advice!
Good, the Insert was made to just slide into hearth and use the existing chimney, so they all don't have an easy way to connect the liner. That was done with a boot attached to the top of Insert that connects to the liner. Make sure however they attached it, that it has a gasket or is sealed to the insert top.
The place where they were made was not a large factory like you would think. It's close to where New Yorker Boilers were made too. About an hour and a half south of me. I used my truck to pick up a new stove there in the early 80's for someone, and the guy working there took me right in the back where they were assembled, took an air hose and blew the dust and debris from one and helped load it in the truck.
The place where they were made was not a large factory like you would think. It's close to where New Yorker Boilers were made too. About an hour and a half south of me. I used my truck to pick up a new stove there in the early 80's for someone, and the guy working there took me right in the back where they were assembled, took an air hose and blew the dust and debris from one and helped load it in the truck.
Yes. From what I understand they were produced in trumbuarsville. Which is about 5 minutes from where I live.
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