Strange Glass Problem - Oslo

[cgeiger]

Hi - It's been awhile since I last posted (sometime in last year's burning season). As I sit here by the side of the low fire I have burning in my Jotul Oslo, watching a tenuous gridiron struggle between Washington and Dallas, I figured I would come to the ever reliable font of woodburning information that is the Hearth.com forums. And so, I being my appeal for knowledge here.

In short, I noticed the other day that there was a strange brown, flamelike shape in my usually pristine stove glass. Figuring a log might have rolled against it, causing the usual buildup of creosote, I cleaned the door. No dice. Upon closer inspection, I realized that the strange, semi-transparent shape is inside the glass. Looking from the front or back you can see the parallax between it and the foreground/background.

During the day, my wife usually keeps the stove going so it's possible it might have happened then - I really don't know. Usual stove top temps are in the 400-500s depending on the wood, desired heat, etc. Has anyone seen this before? Is the glaze on the ceramic doing something strange?

Here's a couple pics if it helps.

 

[begreen]

I'm wondering if something touched the glass while the stove was hot and melted. Is it possible that this is on the outside of the glass?

 

[cgeiger]

That was one of my original ideas, but I scrubbed it with a couple different items to test and it didn't budge. Judging by it's shape and "thickness" I would guess that a fingernail/credit card/etc. would have at least scratched it.

If it matters at all, I had noticed in recent fires that the glass would occasionally display a mother-of-pearlesque swirl in a few spots. These along with any buildup usually cleared up in my twice monthly glass cleanings so I dismissed it as an interesting byproduct of normal burning.

 

[smokingolf]

Hey Blue, who won the game?

Brian

Cowboys teritory of Central CT.

Sorry

 

[cgeiger]

Being a staunch Redskins fan I am very pleased with how well the defense played - but in the end it simply wasn't enough.

Seriously though, has anyone seen this kind of problem with the glass? It's not a show stopper - it's low enough to blend in with the wood but I'd like to know if it will continue or if I'm doing something wrong that's causing it. FWIW this is season 2 of full-time burning (still shoulder season here in Northern VA though) so I'm kind of surprised.

 

[savageactor7]

Next time the stove is cold maybe try scraping with a razor?

 

[littlesmokey]

What wood are you burning? Could it be a "Pitch-pocket" that spit out at the glass? They can be like a blowtorch sometimes. The effect on the glazing can be weird, too. I've had a few spots from pinion logs that never seem to dry getting psychodelic with the glass.

 

[ashpanannie]

I have had a few of those stubborn marks myself. You absolutely cannot feel them or really tell which side they are on, but they do wind up being inside! You have to work patiently with warm stove ash and scrub in every direction and then in circles before you finally see any results. Mine all came off in the end without having to resort to a razor blade. Do you use any sort of cleaner on your inside glass that might produce the colored effect? So far I just use ash and wet paper towels.

 

[Corey]

Nothing you could do during burning (or any other time, really) would put something *inside* the glass (as opposed to *on* the inside of the glass - if I'm reading correctly). About the only possibilities are it was always there and you just didn't notice it until now or something was manufactured in the glass and possibly didn't show up until it was heated - and possibly changed color. Additionally if it's inside the glass no amount of cleaner, scraping or other effort will remove it.

Depending on the age of the stove, you might be able to contact the manufacturer/dealer and see if they would offer a replacement. If that doesn't work, you could try increasingly aggressive cleaning products - but again, I wouldn't have much hope if it's inside the glass. You might also try heating the area as hot as possible with a propane or even oxy acetylene torch. Maybe you could burn the stain out. Beyond that it's either live with it or replace the glass.

 

[tutu_sue]

I had the end of a log leave a similar mark on my F3. I used some Flitz on a damp paper towel to take it off.

 

[firefighterjake]

Nothing you could do during burning (or any other time, really) would put something *inside* the glass (as opposed to *on* the inside of the glass - if I'm reading correctly). About the only possibilities are it was always there and you just didn't notice it until now or something was manufactured in the glass and possibly didn't show up until it was heated - and possibly changed color. Additionally if it's inside the glass no amount of cleaner, scraping or other effort will remove it.

Depending on the age of the stove, you might be able to contact the manufacturer/dealer and see if they would offer a replacement. If that doesn't work, you could try increasingly aggressive cleaning products - but again, I wouldn't have much hope if it's inside the glass. You might also try heating the area as hot as possible with a propane or even oxy acetylene torch. Maybe you could burn the stain out. Beyond that it's either live with it or replace the glass.

If I'm reading the OP's thread right you and I are on the same page . . . and the other folks here suggesting ash and newspaper, razors, etc. have not read the post for what it says . . .

The OP says he believes this is inside the glass . . . not on the side of the glass in the firebox . . . which would of course could be caused by pitch or a split rolling against the glass . . . and in which case it could be removed by razor, damp newspaper, cleaning products, etc. . . . but if Cozy and I are reading this right, this mark is inside the glass and no amount of cleaning, scraping, etc. would remove this.

I am also in agreement with Cozy . . . sounds like a possible defect and short of replacing the glass or hoping that high heat or time might make the mark disappear would not hold out much hope.

If it's any consolation for the OP, you're kind of special since this is the first I've read of this problem. Of course, this is one of those times when being special isn't so great. Good luck and let us know how you make out.

 

[Dexter]

ceramic stove top cleaner applied with oooo or ooooo fine steel wool WILL remove that mark.

Dexter

 

[tutu_sue]

I read in my Jotul manual that IR coated glass is used. From what I understand, the ceramic glass is known as dichrioc glass, which means it has an IR reflective coating on it. The reflective coating will make it appear to have a space between an object and it's reflection. The coating makes the glass look slightly orange at certain viewing angles, too.

I found this on the web: The most straightforward way to determine which side has the coating requires the use of a pencil or similar object. Just hold the pencil at a slight angle so that the tip is lightly touching the surface of the glass. Observe carefully to see if the reflection of the pencil tip in the glass is directly touching or if there's a space between the actual tip and its reflection. If there's a space, the coating (dichroic or irid) is on the opposite side; no space means the coating is on the top surface next to the pencil.

 

[littlesmokey]

I read in my Jotul manual that IR coated glass is used. From what I understand, the ceramic glass is known as dichrioc glass, which means it has an IR reflective coating on it. The reflective coating will make it appear to have a space between an object and it's reflection. The coating makes the glass look slightly orange at certain viewing angles, too.

I found this on the web: The most straightforward way to determine which side has the coating requires the use of a pencil or similar object. Just hold the pencil at a slight angle so that the tip is lightly touching the surface of the glass. Observe carefully to see if the reflection of the pencil tip in the glass is directly touching or if there's a space between the actual tip and its reflection. If there's a space, the coating (dichroic or irid) is on the opposite side; no space means the coating is on the top surface next to the pencil.

This may be a way of finding the location. Use the pencil on the stain and see if the tip touches. It is possible the damage or mark is on the "glass" under the coating.

 

[begreen]

Bring a picture into the dealer so that they see what you are seeing. I suspect they will want to see if it burns off over time. Seems worth running the stove with a week's worth of hot fires to see if it goes away, gets worse or stays the same. If no improvement, ask the dealer to schedule you for a warranty glass replacement.

 

[cgeiger]

Thanks for all your posts - this really does have me befuddled. When I clean my glass I do use a bit of ash on a wet paper towel and scrub until it's clean. Then, I buff it out with a dry paper towel. I can give the buffing another try but if some part of the IR coating DID fail then that would readily explain the parallax I see between the "stain" and the two sides of the glass. I will definitely try the pencil trick just as soon as it warms up enough to let the fire die down. For now, I just threw on a coupla splits :D If all else, fails I will definitely head back to the dealer (great guy over in Buckeystown, MD) for a warranty replacement (thanks, BeGreen).