Why does this happen?

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Handy Daddy

New Member
Jan 6, 2015
16
NJ
I cleaned my glass completely. I started this morning with a cold stove. Had a great start with kindling and small splits from 2+ year old seasoned wood.

Take a look at this picture. Almost immediately I got this dark spot on the glass on the left side of the left door. The air was wide open for the cold start. It started happening almost immediately. The right door glass is spotless. The worst part is that it doesn't burn off while hot. My IR gun read about 450-500 on the left door frame (as I'm typing this) and it still won't burn off.

I've posted previously that my only complaint about my Regency 90 is the air wash that doesn't work that well on a long, low burn. But this is really frustrating. This happened on startup with wide open air and seasoned wood.

Any theories on why this happened?

Thanks!

*EDIT: not sure why the pic is showing upside down.
 

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I will occasionally get a black spot on the glass if the end of a round/split is very close to the glass like when a N-S load might shift. It is easily wiped clean when the stove cools a bit. It may be due to that piece of wood being less dry than than it should be.
 
Could be that your gasket has a leak there. Try a dollar-bill test: Hold a dollar bill over the door frame. Close the door and see if you can pull out the bill. It should offer some serious resistance. If you can easily slip it out the gasket needs to be replaced.
 
Was a split closer to the glass in that spot? Are you loading north to south, or east to west?
Outgassing of splits will do that if you load n-s and the splits are near the glass.
Door gasket point Grisu brought up is worth checking into, and easy enough to do.
Although usually the hinge side is the tightest area, but anything is possible.
It should burn off, did you try running the stove a little hotter to see if that cleans it off?
Does it happen on the same spot/area constantly?
 
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Can you post a shot of that area with the door open showing the gasket side of the door?
 
Was a split closer to the glass in that spot? Are you loading north to south, or east to west?
Outgassing of splits will do that if you load n-s and the splits are near the glass.
Door gasket point Grisu brought up is worth checking into, and easy enough to do.
Although usually the hinge side is the tightest area, but anything is possible.
It should burn off, did you try running the stove a little hotter to see if that cleans it off?
Does it happen on the same spot/area constantly?

It was loaded East/West.

As soon as the stove cools, I am going to check the gasket with the dollar bill.

No matter how hot I runt he stove (up to 650) nothing burns off the glass.

It usually happens on this spot but never immediately after a cold start. This literally happened with 5 minutes.
 
Can you post a shot of that area with the door open showing the gasket side of the door?

I bought the unit new and started burning in November. About 3/4 of a cord so far.

Not sure why these pics don't upload oriented properly.
 

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Rotate your iPhone when you take the pics.
 
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In the picture, the gasket doesn't appear to be making contact with the stove body.
 
Certainly does not look like equal pressure of the gasket to the stove body. Just basing that on the tell tale mark of the gasket itself.

Frustrating for sure.
 
Guys, I need some more info on this dollar bill test. I just did it. How hard should I have to pull to get the dollar bill to slide?

Also, if the gasket isn't sealing properly could this be the problem? If air leaks in around the gasket why would it cause a build up on the door? Is it because you're cooling the glass?
 
Pretty hard without ripping the bill apart. No resistance or just a slight tuck won't be enough.

Cold air will come in that side which will not be hot enough to burn the smoke particles. It also screws up the airflow from the airwash.
 
Guys, I need some more info on this dollar bill test. I just did it. How hard should I have to pull to get the dollar bill to slide?

Also, if the gasket isn't sealing properly could this be the problem? If air leaks in around the gasket why would it cause a build up on the door? Is it because you're cooling the glass?
There should be some resistance as you pull out the bill. That will indicate pressure on the gasket, which is what seals it. The harder you have to tug it the tighter the seal. But even moderate pressure is sufficient. Test at multiple locations around the door and note the differences in tension when pulling out the bill.
 
Just wanted to post an update on this. I adjusted the door latch and checked the gasket using the dollar bill test. It's better, tight in most areas, could be tighter in others. I burned two fires and the results are definitely better. Not perfect but better.
 
Also be advised this is the time of year that wood that was down to 12%MC wet basis last fall is sucking every drop of humidity out of the air it can find.

I shedded 12-16% In September, a month in to the freeze/thaw daily cycle I can't hardly find anything dryer than 18%.
 
Try to fluff up your gasket with a pic or something to see if that makes a diff.
 
I cleaned my glass completely. I started this morning with a cold stove. Had a great start with kindling and small splits from 2+ year old seasoned wood.

Take a look at this picture. Almost immediately I got this dark spot on the glass on the left side of the left door. The air was wide open for the cold start. It started happening almost immediately. The right door glass is spotless. The worst part is that it doesn't burn off while hot. My IR gun read about 450-500 on the left door frame (as I'm typing this) and it still won't burn off.

I've posted previously that my only complaint about my Regency 90 is the air wash that doesn't work that well on a long, low burn. But this is really frustrating. This happened on startup with wide open air and seasoned wood.

Any theories on why this happened?

Thanks!

*EDIT: not sure why the pic is showing upside down.


Who told you the wood was 2 + old seasoned wood, and what type is it ?

bob
 
Who told you the wood was 2 + old seasoned wood, and what type is it ?

bob

I split, stacked and covered it myself two years ago after Sandy left me with a lot to clean up! It's mostly elm.
 
Wood may just not be dry enough.
Depends how, where you stack it, and if it gets good sun & wind to help dry it out.
 
Just another check that is sometimes overlooked, be sure your gasket is adhered to your door all the way around, pull on the gasket all the way around the door to be sure it is adhered to the door, if it is not it will leak, and could very easily pass the dollar bill test.
Also leaks can occur where the ends of the gasket come together.
Small fires and not so dry wood can cause a lot of crap on the window.
Another check you can do is get a straight edge check the flatness of the front of your stove and your door.
How old is your gasket
Is the gasket on your stove the proper thickness
 
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