Jotul f600 glass

[fraxinus]

It has been many years since I have posted on Hearth.com. I currently am baffled by the following problem: The hinge side of the left hand door on my Jotul f600 develops a haze each day after a few hours of operation. This is not creosote. It looks like very fine gray ash. It is extremely easy to wipe off with a damp paper towel and can even be brushed off with a soft bristled brush. I clean the glass in both doors almost daily. The problem area fills about a third of the glass on the hinge side and always reappears.

In all other ways the stove is operating as it always has, but this area of reappearing haze is a new development.The wood, about 90% maple, is well below 20% moisture content. All gaskets were checked this fall. The glass itself appears to be tight, and there's no evidence of air leaks anywhere.

After a number of years of use, none of the glass is in the pristine condition seen when the stove was brand new, but the remainder of the left hand door and no part of the right hand door shows the easily removed but constantly recurring haze on the hinge side of the left hand door.

The only explanation that comes to mind is that somehow this one area of glass on the left hand door has become so etched that super fine fly ash adheres only in this one spot. This doesn't really seem very likely.The front doors are rarely opened during the months of heating and I have always been extremely careful about keeping the glass clean.

So any thoughts/suggestions would be much appreciated, especially if you think there is any danger indicated by what I have described. If you think I'm just going to have to live with this problem until the glass is replaced, tell me that, too.

Thank you.

 

[DAKSY]

Recheck the door gasket in that area.
Does it pass the "dollar bill" test?

 

[CentralVAWoodHeat]

Do you mean left hand as you look at the stove or on the stove's own left?

 

[fraxinus]

Recheck the door gasket in that area.
Does it pass the "dollar bill" test?

Dollar bill test seems fine. I also checked for leaks around the door with smoke because the door design on this particular stove makes the dollar bill test difficult. No sigh of air leaks.

 

[fraxinus]

Left side refers to the front of the stove. Sorry for the lack of clarity in the original post.

 

[CentralVAWoodHeat]

Left side refers to the front of the stove. Sorry for the lack of clarity in the original post.

Gotcha so the same side as the side loading door.

With my F600, if I open the side door when there is anything above a few coals, the draft is strong enough to blow a big puff of ashes around. It will usually end up with a good amount on that left side glass. However after the next burn the airwash will have cleaned it away. How is the gasket around your ash clean out door?

Also, how often to you load using the front doors versus the side door?

 

[fraxinus]

Gotcha so the same side as the side loading door.

With my F600, if I open the side door when there is anything above a few coals, the draft is strong enough to blow a big puff of ashes around. It will usually end up with a good amount on that left side glass. However after the next burn the airwash will have cleaned it away. How is the gasket around your ash clean out door?

Also, how often to you load using the front doors versus the side door?

Thank you CentralVAWoodHeat for your thoughts.

Facing the front of the stove, the glass in question is on the left and the loading door is on the right. I use the loading door exclusively during the heating season for adding wood. The center front doors are never opened when there is a fire going. I have also never experienced a puff of ashes when using the side door as long as I have remembered to open the draft control when adding wood.

For a bit I thought you might be onto something when you mentioned the ash tray door gasket because the problem area is directly above where the cleanout door latches on the lower left.. I did check all gaskets back in the fall using a dollar bill and an incense stick. No more incense sticks available, but I just checked for air leaks using a candle flame. Did not bend or waver at all. I'll retry the dollar bill test tomorrow. Any other thoughts?

 

[Nick Mystic]

I also have an F600 and do all my loading from the side, same as you. On the rare occasion when I do open the front doors, on a cold stove, I've noticed that the glass panels in each door sometimes have shifted and I have to re-position them by loosening the tab fasteners that are held on with allen wrench bolts. There is gasket material between the glass and doors and the glass panels slip off center from the space they sit in. Yours might be doing the same thing and your left door might be letting some air seep in causing the problem you describe.

 

[CentralVAWoodHeat]

I also have an F600 and do all my loading from the side, same as you. On the rare occasion when I do open the front doors, on a cold stove, I've noticed that the glass panels in each door sometimes have shifted and I have to re-position them by loosening the tab fasteners that are held on with allen wrench bolts. There is gasket material between the glass and doors and the glass panels slip off center from the space they sit in. Yours might be doing the same thing and your left door might be letting some air seep in causing the problem you describe.

Interesting.....I have never noticed glass shifting on mine but that is a really good thing to look for.

 

[CentralVAWoodHeat]

Thank you CentralVAWoodHeat for your thoughts.

Facing the front of the stove, the glass in question is on the left and the loading door is on the right. I use the loading door exclusively during the heating season for adding wood. The center front doors are never opened when there is a fire going. I have also never experienced a puff of ashes when using the side door as long as I have remembered to open the draft control when adding wood.

For a bit I thought you might be onto something when you mentioned the ash tray door gasket because the problem area is directly above where the cleanout door latches on the lower left.. I did check all gaskets back in the fall using a dollar bill and an incense stick. No more incense sticks available, but I just checked for air leaks using a candle flame. Did not bend or waver at all. I'll retry the dollar bill test tomorrow. Any other thoughts?

Got it-thanks for the clarification.

We likely get that puff of ash because of how strong our draft is. We added two 45 bends in the pipe when installing the F600 and it still drafts like crazy.

You said the stove is performing normally but have you checked the 'doghouse' cover where your air comes in at the front of the firebox? Could be loose or clogged.

 

[fraxinus]

Many thanks to everyone who contributed thoughts and ideas.

This morning I rechecked the ash door, side loading door and central doors with the dollar bill method. Tight and sound in every case. The doghouse cover was removed, vacuumed underneath and lubricated with powdered graphite in September. This moves easily and regulates air flow as it always. has. No sign of out of place or loose glass in either door.

I am back, I guess, to my original idea that this one area of the left hand glass somehow become seriously enough etched so that fly ash accumulates in this area. I came very close to running out of wood altogether last year so was burning some pretty gnarly stuff toward the end. This might be a partial explanation. This also marks the 10th winter of using this stove, so close to 50 cords have been burned in it. Since the problem area has not increased in size and the stove is operating normally in all ways, I'll live with it for the rest of this season and decide over the summer if a clearer view of the fire is sufficient justification for new glass.