Dirty PH glass with 3YR Wood

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Berner

Berner

Feeling the Heat
Feb 1, 2012
388
Eastern, MA
This winter marks the first year I have been able to burn three year seasoned wood. Moisture content says between 10-15%. So how is it that when I turn the air almost all the way down on the PH that the bottom half of the glass still turns black? Is it possible my 3 year seasoned wood is still not quite good enough?
 
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give it more air, probably not getting enough air through the airwash to create the barrier of air between the fire and the glass, there is a point where wood can be too dry....
 
Was your glass getting dirty in the previous years in the same spots with the other wood?
Do you fill your box very tight with wood?
 
Ram 1500 with an axe... said:
Was your glass getting dirty in the previous years in the same spots with the other wood?
Do you fill your box very tight with wood?
Click to expand...

Yes last year I was using wood that was seasoned two years. The glass got dirty in the same spots. There was definitely a big improvement this year over how easily it got dirty last year. I guess I was just hoping that this year with 3 year seasoned wood all that would be fixed.

Yes I do fill the firebox almost all the way to maximize burn times. I usually try and load full in the morning, half full when I get home around 4 and then full load before bed around 9. The morning and evening loads have far more dirty glass than the half full afternoon load.
 
I think the problem is not enough air. My stove uses the primary air supply (the one you are shutting down all the way) as the airwash to keep the glass clean. If I turn the air down all the way, the glass can get dirty even though the smoke that smudges the glass gets burned up before it leaves the stove - so I can get dirty glass and a clean burn at the same time. Try giving it more air.
 
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bobdog2o02 said:
give it more air, probably not getting enough air through the airwash to create the barrier of air between the fire and the glass, there is a point where wood can be too dry....
Click to expand...

Too dry? I thought the drier it is the less likely it is to dirty the glass? If I jack the air up I won't get the long CAT burn times that I'm shooting for.
 
I have only had my PH for a few days, but i noticed that when the small air hole in the front center between the andirons is either partially or completely plugged or blocked by coals or wood that the bottom portion of the glass gets black and dirty. I started leaving some space around that hole and havnt had an issue the last 2 days. I use a carbon arrow shaft during reloads to blow any ash accumulation off of and from around the hole. The arrow shaft also is nice for blowing the ash accumulation off of the bottom of the glass where it likes to gather sometimes.
 
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Berner said:
This winter marks the first year I have been able to burn three year seasoned wood. Moisture content says between 10-15%. So how is it that when I turn the air almost all the way down on the PH that the bottom half of the glass still turns black? Is it possible my 3 year seasoned wood is still not quite good enough?
Click to expand...
Not sure if it's the wood, the draft, or just slight differences in individual PH stoves. I'm burning 3 years old hickory and oak and my glass stays very clear all through the burn cycle. I am attaching a picture from this morning after a 14 hour burn on the lowest air setting possible. Glass is very clean with just a half inch area of darker stuff on the left side bottom. The stove is at 206* and the air is wide open and the cat disengaged. I will be reloading in about 30 minutes. I usually load the stove about 70% full (4 to 5 splits). Perhaps the PH's that get dirty glass are more air tight and capable of even longer burn times? 007.JPG
 
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I bet.....
Your wood is not too dry and that has nothing to do with it.....
If your not leaving enough air between splits the black smoke ( or what ever it is) has to go somewhere before going up the stack. You are forcing it against the glass on the bottom before shooting up and out.... I get that when I play around and fill my box up and I'm burning all under 20% hardwoods. I don't know your unit but try to make a fire using less splits with space between like the log cabin or teepee method when your home for the day and see how that works after cleaning your glass before you try this. You may get less heat but clean glass this way so you may have to decide which is more important, but i like playing around with different loads as I'm still learning too.....
 
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TheRambler said:
I have only had my PH for a few days, but i noticed that when the small air hole in the front center between the andirons is either partially or completely plugged or blocked by coals or wood that the bottom portion of the glass gets black and dirty. I started leaving some space around that hole and havnt had an issue the last 2 days. I use a carbon arrow shaft during reloads to blow any ash accumulation off of and from around the hole. The arrow shaft also is nice for blowing the ash accumulation off of the bottom of the glass where it likes to gather sometimes.
Click to expand...
Great point, knowing about keeping those air holes open is extremely important to good operation on the stoves. I was lucky to ask a question and be told by the guy that sold me the unit about them, otherwise I would never have known because you can't see them on mine......
 
TheRambler said:
I have only had my PH for a few days, but i noticed that when the small air hole in the front center between the andirons is either partially or completely plugged or blocked by coals or wood that the bottom portion of the glass gets black and dirty. I started leaving some space around that hole and havnt had an issue the last 2 days. I use a carbon arrow shaft during reloads to blow any ash accumulation off of and from around the hole. The arrow shaft also is nice for blowing the ash accumulation off of the bottom of the glass where it likes to gather sometimes.
Click to expand...

I will try this. I usually rake the coals and leave a hole all the way to the grate in the front center. However I've never actually seen this small air hole or tried cleaning it out. Where exactly is it located?
 
Ram 1500 with an axe... said:
I bet.....
Your wood is not too dry and that has nothing to do with it.....
If your not leaving enough air between splits the black smoke ( or what ever it is) has to go somewhere before going up the stack. You are forcing it against the glass on the bottom before shooting up and out.... I get that when I play around and fill my box up and I'm burning all under 20% hardwoods. I don't know your unit but try to make a fire using less splits with space between like the log cabin or teepee method when your home for the day and see how that works after cleaning your glass before you try this. You may get less heat but clean glass this way so you may have to decide which is more important, but i like playing around with different loads as I'm still learning too.....
Click to expand...

I think you are right. When I burn my afternoon half loads the glass stays almost perfectly clean. It's only when I fill the stove up all the way does it do this. I will experiment with the small air hole and leaving space between splits.
 
Haha, i just reloaded and its fully ablaze or i would take a picture. Its about the size of a pencil width, maybe a tad bigger, and is directly in the middle of the andirons, about an inch or two down. Its on the cast piece below the window. but before the ashpan grate starts.
 
If its covered in ash it can be impossible to spot. The only reason i knew to keep it clear was reading posts about the PH over the last few months.
 
I wouldn't worry about it. I get some black on the lower glass too when burning low. I think that's pretty common with the PH. Mine is set almost exactly like your setup. It always burns off by the end of the burn. Just pretend you have a Blaze King for a few hours.
 
Berner said:
Too dry? I thought the drier it is the less likely it is to dirty the glass?
Click to expand...
It can be to dry. If the wood is very dry it will off gas to quickly causing black smoke as well as dirty glass. I doubt this is the issue for you though considering your mm findings. I would suspect this if your wood wasnt registering anything on your meter. I get dirty glass if I have a split to close to the glass. Have you done the dollar bill test?
 
TheRambler said:
Haha, i just reloaded and its fully ablaze or i would take a picture. Its about the size of a pencil width, maybe a tad bigger, and is directly in the middle of the andirons, about an inch or two down. Its on the cast piece below the window. but before the ashpan grate starts.
Click to expand...

I figured Super Bowl Sunday probably wasn't a good day to ask if anyone has a cold stove to take a picture inside. I'm going to let mine to cold tomorrow and see if I can figure out where it is.
 
My experience with the PH, this only happens with wet wood. It burns off once the fire gets hot. If you burn the entire cycle with the air under 400 and you have used wet wood, it may not burn off.

The air hole in my PH is considerably smaller than the diameter of a normal wooden pencil. Maybe they have increased the size of the air hole?

If that is covered the coals don't burn down as well, for sure. But it has not seemed to have any effect in stopping wet wood from producing a black or brown film on a portion of the glass.

Three year seasoned, I am surprised you are encountering the problem. Is your wood oak?

Tenn Dave, nice install, handsome stove. And very clean. Looks brand new.
 
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ksc said:
I wouldn't worry about it. I get some black on the lower glass too when burning low. I think that's pretty common with the PH. Mine is set almost exactly like your setup. It always burns off by the end of the burn. Just pretend you have a Blaze King for a few hours.
Click to expand...

Last year I took the philosophy of as long as it's temporary it's probably not a big deal. However now my glass has some permanent etching on it where the ash has melted onto the glass. I don't know if it's related but this season I'm trying to keep the glass as clean as possible.
 
It's the air. I pack my stove with Eco Bricks I have the stove at 600-650 secondaries from hell and if I cut the air too much I end up with dirty glass.
 
Seanm said:
It can be to dry. If the wood is very dry it will off gas to quickly causing black smoke as well as dirty glass. I doubt this is the issue for you though considering your mm findings. I would suspect this if your wood wasnt registering anything on your meter. I get dirty glass if I have a split to close to the glass. Have you done the dollar bill test?
Click to expand...

I have not done the dollar bill test. That's to make sure the loading door has a good seal correct?
 
Berner said:
I have not done the dollar bill test. That's to make sure the loading door has a good seal correct?
Click to expand...
Yeah, a leaky door will also lead to dirty glass.
 
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