Ash Cakes

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FrankM

Member
Jan 25, 2008
30
Eastern Pennsylvania
What causes ashes to cake in to small chunks? I am trying a new brand of pellet - Somerset. They seem to burn very well and hot but when cleaning the stove I find ash cakes. I don't recall ever seeing this in the past five years of burning my stove.
 
More info on your set-up? What kind of stove are you running? What are you burning at? (Settings)? OAK? Clean stove? Clean vent? I'm burning the Somersets and they seem a little ashy but MUCH better than others I tried. i.e.- Penningtons, Inferno's....
 
I am burning an Englander 25pdvc. I have hooked up to a wall thermostat so the settings vary. Its not a big deal but I just never noticed this before. Overall I am happy with the burn and heat of the Somerset pellets. I did turn my low air burn setting up a bit to see if that would help. I don't think it is a cleaning issue as I do a quick clean everyday and I give it a good cleaning every other day.
 
FrankM said:
I am burning an Englander 25pdvc. I have hooked up to a wall thermostat so the settings vary. Its not a big deal but I just never noticed this before. Overall I am happy with the burn and heat of the Somerset pellets. I did turn my low air burn setting up a bit to see if that would help. I don't think it is a cleaning issue as I do a quick clean everyday and I give it a good cleaning every other day.

I had a slight clinker issue when i switched to Barefoots from the Premier hardwoods. Raised the LBA i notch and that cured it.

As for your cleaning, when was the last time the stove was deep cleaned? Both blowers removed & cleaned, burn pot & impingement plate removed and everything brushed & vacuumed, ENTIRE exhaust pipe cleaned with brush & vacuum, etc.

What were your lower button settings before the switch to the Somersets?
 
I have two Harman stoves and have the same issue when burning Somersets. The ash cakes build up on both the left and right side of the burn pot. Its really not a big deal as I scrape them into the ash pans a few times daily.

Even with the ash cake formation, Somersets have far less overall ash than other pellets that I've burned plus they are a much hotter burning pellet.

We will continue to use Somersets here and will purchase another full semi load again this spring.
In my opinion, they are one of the best pellets on the market today.
 
It is all the inorganic material in the pellets like sand, dirt, minerals, Ect.... When burning the melt and clump together creating clinkers or ash cakes.
 
maglite67 said:
It is all the inorganic material in the pellets like sand, dirt, minerals, Ect.... When burning the melt and clump together creating clinkers or ash cakes.

Does the inorganic material when burned turn to a dark brown ash? Kinda looks like just plain old dirt. And the other ash is grey and white in color.
 
Lineman30 said:
maglite67 said:
It is all the inorganic material in the pellets like sand, dirt, minerals, Ect.... When burning the melt and clump together creating clinkers or ash cakes.

Does the inorganic material when burned turn to a dark brown ash? Kinda looks like just plain old dirt. And the other ash is grey and white in color.

The color depends upon a lot of things, if you have control of your burn air you can increase it if the color changes and the ash becomes finer it will get blown out of the pot (in this case the pellets weren't getting enough air to burn completely before getting more pellets dumped into the pot and more ash created, this eventually leads to burn pot overflow). You can also accomplish the same thing by reducing your feed trim if you have such a feature. Dense pellets can present burn problems for some stoves.

If you have control over how your stove burns and this still happens it is likely there is a large amount of inorganic matter in the pellets, in particular salts. Enough ash staying in the pot under this condition will tend to fuse the ash into fairly hard clumps called clinkers, these tend to look a bit glassy and resemble lava in texture.
 
SmokeyTheBear said:
Lineman30 said:
maglite67 said:
It is all the inorganic material in the pellets like sand, dirt, minerals, Ect.... When burning the melt and clump together creating clinkers or ash cakes.

Does the inorganic material when burned turn to a dark brown ash? Kinda looks like just plain old dirt. And the other ash is grey and white in color.

The color depends upon a lot of things, if you have control of your burn air you can increase it if the color changes and the ash becomes finer it will get blown out of the pot (in this case the pellets weren't getting enough air to burn completely before getting more pellets dumped into the pot and more ash created, this eventually leads to burn pot overflow). You can also accomplish the same thing by reducing your feed trim if you have such a feature. Dense pellets can present burn problems for some stoves.

If you have control over how your stove burns and this still happens it is likely there is a large amount of inorganic matter in the pellets, in particular salts. Enough ash staying in the pot under this condition will tend to fuse the ash into fairly hard clumps called clinkers, these tend to look a bit glassy and resemble lava in texture.

I've done basically what you described and I still have cake on the sides and the pot full of ash. There are no unburnt pellets. Woke up this morning and the pot was 3/4 full of ash and still burning. Maybe I'll continue to reduce the rate. But when I do I drastically lose my 4-6 inch flame on high. I never have hard like clinkers but they are soft wads of ash that breakup when touched with a putty knife.
 
Lineman30 said:
SmokeyTheBear said:
Lineman30 said:
maglite67 said:
It is all the inorganic material in the pellets like sand, dirt, minerals, Ect.... When burning the melt and clump together creating clinkers or ash cakes.

Does the inorganic material when burned turn to a dark brown ash? Kinda looks like just plain old dirt. And the other ash is grey and white in color.

The color depends upon a lot of things, if you have control of your burn air you can increase it if the color changes and the ash becomes finer it will get blown out of the pot (in this case the pellets weren't getting enough air to burn completely before getting more pellets dumped into the pot and more ash created, this eventually leads to burn pot overflow). You can also accomplish the same thing by reducing your feed trim if you have such a feature. Dense pellets can present burn problems for some stoves.

If you have control over how your stove burns and this still happens it is likely there is a large amount of inorganic matter in the pellets, in particular salts. Enough ash staying in the pot under this condition will tend to fuse the ash into fairly hard clumps called clinkers, these tend to look a bit glassy and resemble lava in texture.

I've done basically what you described and I still have cake on the sides and the pot full of ash. There are no unburnt pellets. Woke up this morning and the pot was 3/4 full of ash and still burning. Maybe I'll continue to reduce the rate. But when I do I drastically lose my 4-6 inch flame on high. I never have hard like clinkers but they are soft wads of ash that breakup when touched with a putty knife.

That is exactly what forms in my pot when I use certain pellets. When I turn the stove off to clean it, the ash wad glows orange for 5-10 minutes after the flame dies. It does not appear to effect flame quality or air flow through the pot.
 
Depends on how much is in the pellets depends on how it forms some will be like a pumice stone or lava rock. Some will make a black glass like or coal like clinker. Most of the time it will stay in the burn pot but sometimes it will blow out and mix with ash. On of those multiple answer questions.
 
I removed both blowers cleaned them back to new in September same with the burn pot. I removed that and cleaned out all of the side holes very well. I take the plate off every other day and clean (even use sos pad) Took the exhaust pipe cleaned with brush & vacuum back in September. maybe I will do that again tonight. Basically back in September I went over everything include all new gaskets. Door and glass included. My low fuel is set at 3 and low air at 7. Used to run at 3 & 5 but a stepped it up to 7 a couple ofdays ago. I think this summer I am going to take the stove out in to the back yard and blow it out with the compressor. My brother-in-law did his this way last summer and he said his stove is burning the way it did 10 years ago. He said it gets real dirty when blowing out. But that is probably the best way to get all of the inner and outer nooks clean.
I must say that the Somerset pellets have been the best I have burned so far. The flame is high the heat is hot and I don't seem to be using as many pellets. Gained a little over a 1/2 a day compared to the Pres to Logs and the Penningtons.

Thanks for all of your replies.
 
I did an air compressor clean on a 25-pvdc. It got a full vent pipe scrub also. It has an OAK installed. It was cleaned to like new condition. The settings are mode "C", heat = 4, fan = 7.
6-4-1 (stock) feed-air-on_temp settings.
It forms the same soft clinkers burning Fireside Ultras. I am not sure if the colder air caused them. When it was warmer out it didn't have them, but maybe it is just variations in the wood pellets.
 
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