New Lopi 1750i glass blackens on sides.

[lp9900]

I’m loving my new woodstove. However, I am consistently getting black suit build up on the sides of the glass. I’ve been reading up on it so have checked the following:

1. Dollar bill test- nice and snug for the most part.
2. Selecting drier pieces of wood.
3. It’s brand new so the gasket is good.

I’m wondering if there’s perhaps
Something wrong with the airwash? Or the glass gasket? If so, how do I check those? Is this normal?

I was under the impression that the Lopi airwash kept the glass clean. My friend has a Lopi Revere (pretty much same unit) and she never gets a blackened window.

Any help would be appreciated. It’s time consuming, and a bit disappointing, to clean the glass every morning.

I do love the heat output on this unit!

 

[begreen]

How well seasoned is the wood? When was the wood split and stacked?

Also, how close are the ends of the splits to the glass?

 

[blacktail]

In addition to begreen's questions, what kind of temp are you running it at?

 

[lp9900]

How well seasoned is the wood? When was the wood split and stacked?

Also, how close are the ends of the splits to the glass?

I have two batches of wood. One is more green than the other. So I’ve been burning the very dry stuff - it’s registering between 7-12% on the moisture meter - even when split open. I’m loading the wood N-S but have tried running E-W. It doesn’t seem to matter how close to the glass it is. Sometimes it’s closer than others, but mostly about 3” away. Even very hot fires at 650+ the area by the door handle still turns black every day.

I can’t run the fire that hot all day as it quickly turns into an 80 degree house. So when I turn down the air control (never all the way) it darkens the glass. That’s when the temps drop to 300-450. But, when I crank the fire back up to burn off the soot off the glass, it doesn’t burn off even when it’s upwards in the 700’s. I have to manually clean it.

I’m unsure of how to test for or know about airwash or glass gasket issues. I wish there was an expert I could call at the company. Blaze King (my old stove) has a company phone number. Lopi does not. My local dealer is not that versed on the technical aspects and fine details.

 

[Pertzbro]

I dont think any stove out there will be 100% clean glass 100% of the time. I clean mine maybe after 2-3-4 burns.

Wet paper towel with https://www.amazon.com/dp/B00120NMNY/?tag=hearthamazon-20

buff it in, let it dry a minute or two and then come back with a dry paper towel to remove (kinda like waxing a car) and then sometimes another piece of dry paper towel to buff to a shine.

Total time to clean is MAYBE 2 minutes.

 

[lp9900]

I dont think any stove out there will be 100% clean glass 100% of the time. I clean mine maybe after 2-3-4 burns.

Wet paper towel with https://www.amazon.com/dp/B00120NMNY/?tag=hearthamazon-20

buff it in, let it dry a minute or two and then come back with a dry paper towel to remove (kinda like waxing a car) and then sometimes another piece of dry paper towel to buff to a shine.

Total time to clean is MAYBE 2 minutes.

2 minutes sounds great! I ordered some to give it a whirl. And most likely it probably is my wood. The wood dealers around here are shady! Shorting cords, green and charred wood. That’s another topic!

Hopefully I can start rolling over my wood stock each year so that I have well seasoned wood.

Also I may try burning one hot fire in the morning and one in the evening rather than a slow burn all day. I don’t know. Just a big ole experiment.

 

[jerrieric]

I've used Vermont glass cleaner for years but have finally wised up and only clean with damp paper towel dabbed in ash. I never believed this would work and at first it was not great but I kept using this method and now it only takes me 15 seconds to clean the glass after a 120 hr 5 day 24/7 burn. I'll never go back to liquids

 

[lp9900]

I've used Vermont glass cleaner for years but have finally wised up and only clean with damp paper towel dabbed in ash. I never believed this would work and at first it was not great but I kept using this method and now it only takes me 15 seconds to clean the glass after a 120 hr 5 day 24/7 burn. I'll never go back to liquids

That’s what I’ve been doing - wet paper towel dipped in ash. But the creosote buildup on the sides of the glass are so thick after my overnight burn it takes a long time and many paper towels to get it off. The fly ash is not a problem. It’s the black creosote stuff. I’m beginning to think that it’s my really dry wood which has some burn scar on it because it has been through a fire that’s causing the issue. As in re burning burnt wood. My other wood (large pieces of red oak) turned out to be really green inside. I just recently bought a moisture meter and on the outside of the red oak it’s about 17/18%. Split it open and it’s upwards of 29-34%. Not a happy camper with the wood guy that delivered it. Plus he shorted me half a cord out of 2 cords.

I’ll keep on trying to get it figured out as I would like to see the fire.

 

[Kevin Weis]

Try a fine plastic brush dampened with ash or even use the Rutland glass cleaner stuff this way. For me this process takes about two minutes one each door.

 

[begreen]

I dont think any stove out there will be 100% clean glass 100% of the time. I clean mine maybe after 2-3-4 burns.

Many stoves including this one should keep a pretty clean glass. Ours gets cleaned only 2-3 times a year and even then there is no soot on the glass.

Even very hot fires at 650+ the area by the door handle still turns black every day.

This sounds like air leakage. It should not be happening. Examine the gasket on the door latch edge. Make sure it is glued in place. Look for any gaps. Try fluffing it up a bit on that edge. See if the door latch can be tightened up little.

 

[webby3650]

Also I may try burning one hot fire in the morning and one in the evening rather than a slow burn all day. I don’t know. Just a big ole experiment

Running slow will cause the glass to darken. When you reduce the primary air, it’s essentially killing your air wash. If this is done too soon, or with under seasoned wood it’s inevitable.

 

[webby3650]

I’m beginning to think that it’s my really dry wood which has some burn scar on it because it has been through a fire that’s causing the issue. As in re burning burnt wood

Overly dry wood won’t cause glazed creosote to build up on the glass. Have you heard that burn scared wood is bad to burn from somewhere?
Is it pine that had its sap crystallized inside it or something? Like fatwood kind of? Fatwood burns dirty and will smoke up the glass if it’s too close to it.

 

[begreen]

Running slow will cause the glass to darken. When you reduce the primary air, it’s essentially killing your air wash. If this is done too soon, or with under seasoned wood it’s inevitable.

Closing the air does not cut off the air fully. Some still goes to the airwash. Also, I wouldn't expect the soot pattern to be just on the latch side if that was the case. I really have to work to get our glass to soot up. Typically this only happens when I have a split that is too long and quite close to the glass. A friend has an Endeavor and it's the same way. The glass always looks great. Underseasoned wood, maybe, but again I wouldn't expect to see the soot just on the latch side.

 

[webby3650]

Closing the air does not cut off the air fully. Some still goes to the airwash. Also, I wouldn't expect the soot pattern to be just on the latch side if that was the case. I really have to work to get our glass to soot up. Typically this only happens when I have a split that is too long and quite close to the glass. A friend has an Endeavor and it's the same way. The glass always looks great. Underseasoned wood, maybe, but again I wouldn't expect to see the soot just on the latch side.

I didn’t get the impression it is only on the latch side.

The air wash is pretty much dead if the primary is shut on these stoves. Most all of the air gets forced through the secondary air tubes. The glass will go black in a hurry if shut the air off too soon on mine.

 

[webby3650]

How tall is the chimney? Insulated liner?

 

[DuaeGuttae]

We used to burn a Revere and the glass stayed pretty clean most of the time. A very low fire with wetter wood could cause some soot, or loading too close to the glass. I noticed particularly that long pine splits would cause darkening of the glass, but it was not glazed creosote as you describe, just smoked up glass. Glazed creosote would come from wet wood, I think.

Can you ask your friend who has the clean glass for a load of wood as a test, or pick your driest pieces and mix them with untreated 2 x 4 pieces?

We had a problem once with a batch of wood in our stacks that was too wet. The splits were larger and not well seasoned. We happened to use that wood just after I had done a door gasket replacement, and I’m pretty sure that my dear husband thought that the poor burn and glaze on the glass meant that I had somehow broken the stove. I don’t know why we didn’t just use a moisture meter on the wood, but I asked my husband to go buy one load of kiln-dried firewood at a local garden center. That quickly showed that the stove was just fine, and we rearranged our stacks to give that wood more time. (We may even have traded some of it with my mother, as she had more than enough dry wood and had more time to let it season. We did that once, but I don’t remember if it was that particular batch.)

Oak is dense and can stay wet a long time. We needed to split ours pretty small and stack it on the south corner of our house to season it properly. If you’be got good wood, that just needs more time, can you buy a compressed product or use pallets to get you through this year and let your wet stuff have another summer?

 

[lp9900]

Many stoves including this one should keep a pretty clean glass. Ours gets cleaned only 2-3 times a year and even then there is no soot on the glass.

This sounds like air leakage. It should not be happening. Examine the gasket on the door latch edge. Make sure it is glued in place. Look for any gaps. Try fluffing it up a bit on that edge. See if the door latch can be tightened up little.

Something I’ve noticed with the dollar bill test is that the side of the door by the handle is very tight and the gasket is quite flattened as a result. The side on the hinge is not tight. The dollar bill can be slid out and the gasket is still quite fluffy. It’s obviously manufactured that way and I can’t make it tighter on that side. I did fluff up the gasket the other day. I ran a very hot fire with more cedar than typical and didn’t shut down the air and the glass stayed nice. But as soon as I close the air down while burning my oak, the sides of the glass get dark again.

 

[begreen]

I just spotted that this is Calif. What part?

What is the moisture content of the oak? What have the outside temps been like?

 

[lp9900]

We used to burn a Revere and the glass stayed pretty clean most of the time. A very low fire with wetter wood could cause some soot, or loading too close to the glass. I noticed particularly that long pine splits would cause darkening of the glass, but it was not glazed creosote as you describe, just smoked up glass. Glazed creosote would come from wet wood, I think.

Can you ask your friend who has the clean glass for a load of wood as a test, or pick your driest pieces and mix them with untreated 2 x 4 pieces?

We had a problem once with a batch of wood in our stacks that was too wet. The splits were larger and not well seasoned. We happened to use that wood just after I had done a door gasket replacement, and I’m pretty sure that my dear husband thought that the poor burn and glaze on the glass meant that I had somehow broken the stove. I don’t know why we didn’t just use a moisture meter on the wood, but I asked my husband to go buy one load of kiln-dried firewood at a local garden center. That quickly showed that the stove was just fine, and we rearranged our stacks to give that wood more time. (We may even have traded some of it with my mother, as she had more than enough dry wood and had more time to let it season. We did that once, but I don’t remember if it was that particular batch.)

Oak is dense and can stay wet a long time. We needed to split ours pretty small and stack it on the south corner of our house to season it properly. If you’be got good wood, that just needs more time, can you buy a compressed product or use pallets to get you through this year and let your wet stuff have another summer?

We used to burn a Revere and the glass stayed pretty clean most of the time. A very low fire with wetter wood could cause some soot, or loading too close to the glass. I noticed particularly that long pine splits would cause darkening of the glass, but it was not glazed creosote as you describe, just smoked up glass. Glazed creosote would come from wet wood, I think.

Can you ask your friend who has the clean glass for a load of wood as a test, or pick your driest pieces and mix them with untreated 2 x 4 pieces?

We had a problem once with a batch of wood in our stacks that was too wet. The splits were larger and not well seasoned. We happened to use that wood just after I had done a door gasket replacement, and I’m pretty sure that my dear husband thought that the poor burn and glaze on the glass meant that I had somehow broken the stove. I don’t know why we didn’t just use a moisture meter on the wood, but I asked my husband to go buy one load of kiln-dried firewood at a local garden center. That quickly showed that the stove was just fine, and we rearranged our stacks to give that wood more time. (We may even have traded some of it with my mother, as she had more than enough dry wood and had more time to let it season. We did that once, but I don’t remember if it was that particular batch.)

Oak is dense and can stay wet a long time. We needed to split ours pretty small and stack it on the south corner of our house to season it properly. If you’be got good wood, that just needs more time, can you buy a compressed product or use pallets to get you through this year and let your wet stuff have another summer?

I’m beginning to think it might be my oak. I’m not sure if my friend would give me a load but I can ask. I’m hoping to have some for next year so that it’s seasoned. Nobody truly sells seasoned wood anymore.

 

[lp9900]

How tall is the chimney? Insulated liner?

The chimney is standard 4’ above the roof line and my guess is about 15’ total? Im not sure exactly.

I don’t believe it is insulated. They just did the flexible steel liner and I didnt see any insulation. How would I do that after the fact?

 

[lp9900]

I just spotted that this is Calif. What part?

What is the moisture content of the oak? What have the outside temps been like?

I live in Sonora - foothills North of Yosemite. The outside temps are between 28-38 as lows and daytime temps have just warmed up into the upper 50’s.

I have two batches of oak. One is a white oak that was through a fire and it’s running an average of 8-9% moisture on the meter. The red oak has a low of 16% and some pieces are as high as 32%. I’m burning mostly the white oak but sometimes will put a larger piece of the red oak but trying to pick the 16-17% moisture content ones. I believe they may be upwards of 22% on the insides it’s obvious they are still green which is why I’m trying to burn the white oak up first.

 

[SpaceBus]

I use coarse paper towels or a bit of newspaper with a tiny bit of water dipped in wood ash if there's soot on the glass. I wipe it with a dry spot when done and it looks like new. Sometimes the glass gets a little hazy, but not black. Just a damp towel takes this off, I'm pretty sure it's just fly ash or solids left behind from steam.

 

[begreen]

I live in Sonora - foothills North of Yosemite. The outside temps are between 28-38 as lows and daytime temps have just warmed up into the upper 50’s.

I have two batches of oak. One is a white oak that was through a fire and it’s running an average of 8-9% moisture on the meter. The red oak has a low of 16% and some pieces are as high as 32%. I’m burning mostly the white oak but sometimes will put a larger piece of the red oak but trying to pick the 16-17% moisture content ones. I believe they may be upwards of 22% on the insides it’s obvious they are still green which is why I’m trying to burn the white oak up first.

Temps are certainly cold enough to promote good draft. Is there a decent height flue system on the stove? If the glass is staying clear with known, dry wood then webby has it right, it's the wood.