F-500 producing large amount of coals?

Could be not dry enough.
Are you loading frequently? Try just loading a full load and let it burn for 8 hrs.
500-550 is not a bad temp.
Ash & Maple should not leave alot of coals, they usually leave alot of ash as opposed to coals.
Prolly ain't dry enough.

It's all just part of the burn cycle, if you're around you can open up the air when you get down to coals, or put some small splits on the coals to help burn them down.

I have the same problem with a Mansfield. Hopefully it's the wood I use, which is not fully seasoned, so this issue will be resolved next year. If I try to burn all coals to ash, I'll end up with a stove that sits for hours not producing any usable heat. I usually end up scooping out large amounts of hot coals and testing the limits of my "ove glove"...

Mad Tom said:

Hogwildz said:

Could be not dry enough.
Are you loading frequently? Try just loading a full load and let it burn for 8 hrs.
500-550 is not a bad temp.
Ash & Maple should not leave alot of coals, they usually leave alot of ash as opposed to coals.
Prolly ain't dry enough.

Click to expand...

I load frequently. If I don't In about an hour my stove temp will drop. Heating a 3100 sqf home with it. Keeps the whole house about 70. Open floor plan with a 15'x15' balcony opening to let the heat upstairs. How long should a 500 burn at say 500 with 1 load of wood?

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There is part of your problem, plus I bet the wood is not as dry as you think.
How long will it run at 500? If it drops in temp quickly you should try opening the air lever up a lil at a time till you get a more steady temp.
Sounds alot like less than optimally dry wood. Heats up ok, and gets to temp, but once you cut the air back, it drops fast. Experiment with the air lever and after its up to temp, leave it open a lil bit, and keep an eye on it.
Frequent loading along with wood on the wetter side, is my bet, exactly what your problem is. It will not sustain a constant higher temp without introducing some air. If you experiment with it, you should find an air setting open enough to keep the higher temps steady, yet not let it run away. Trial and error. You should not have to mess with the wood or load it again for about 8 hrs. Once its in the last part of its burn cycle, then you can open the air up a bit more to burn the coals down and still get some heat from them.

I've found the same thing to be true of the F600, and believe that it is a result of the design of the stoves. All of the air comes from the small openings at the lower front center of the stove. When you decrease the volume of air by partially closing the air control, you also decrease the air velocity. This causes the wood toward the back of the fire box to smolder and turn into charcoal because it has insufficient oxygen. The stronger the draft, the less pronounced this is, but the more you shut down the air, the more charcoal you produce. My solution has been to rake coals forward when adding more wood and allowing most of the wood to burn down considerably before adding more. This is not really a design flaw. The lessened wood consumption in stoves like this is (I think) entirely due to maintaining high internal temperatures with limited amounts of air.

I’ve got the same problem w/ my stove. It seems to happen mostly when I load my stove w/ hardwoods (oak & maple) & bank-down for an overnight burn. It seems to happen a lot less with softer woods.
Either way, don’t waste those coals. Set up a sifting system so you can re-use them (lots of potential heat in them).

Mad Tom said:

Hogwildz said:

Could be not dry enough.
Are you loading frequently? Try just loading a full load and let it burn for 8 hrs.
500-550 is not a bad temp.
Ash & Maple should not leave alot of coals, they usually leave alot of ash as opposed to coals.
Prolly ain't dry enough.

Click to expand...

I load frequently. If I don't In about an hour my stove temp will drop. Heating a 3100 sqf home with it. Keeps the whole house about 70. Open floor plan with a 15'x15' balcony opening to let the heat upstairs. How long should a 500 burn at say 500 with 1 load of wood?

Click to expand...

Ah yes, there's your problem . . . reloading too frequently.

3,100 square feet with a balcony opening . . . tough for many stoves . . . very tough for the Oslo.

I don't know if I really have any good answers for you . . . if you want to maintain the same heat level and reduce coals at the same time about the only suggestion I could make is to slowly open up the air control as you progresss in the burning process . . . usually folks bring the stove up to temp and lower it for maximum burn time . . . and after several hours when the coals are the size of golfballs or so add more wood and start the burning process over again. There is some temperature fluctuations, but if the home is well insulated and the stove is sized properly it tends to work OK with not a lot of wide temp spikes. In your case bringing the stove up to temp, shutting down the air and letting it do its "thing" (i.e. secondary combustion) and then slowly opening the air control once the secondary ends and you're at the large coal stage might be the best suggestion . . . it will not be as efficient, but it should maintain the heat and "burn down" the coals.

That said, another option that I use when the temps are sub-zero and I'm stoking the fire more often (which results in coals) is to toss a small split on to the large pile of coals every few loads and open up the air all the way . . . typically in a half hour or so the bed of coals will be burned down, but you'll still have some heat coming from the stove (albeit not as much as if there was a full load) and you will have enough coals (and more importantly space) to do a full reload at this point.

Burn time varies greatly . . . depends on the home's size, insulation, outdoor temp, wood that is being burned (in terms of species and how wells seasoned it is), what folks prefer for indoor temps, etc. For an average winter day with temps in the high teens to 20s I usually figure I'll have active flames and good sized coals for 4-6 hours and on an overnight fire can get meaningful heat from the fire for 6-8 hours . . . however when the winds are blowing and the temps are sub-zero my burn time is decreased as I am stoking the fire more often to keep the heat levels up.

Thats what happens when you're constantly throwing wood in there to keep warm. The optimum burn is to get a cycle going like others said, where you burn a full load down, then reload. Sometimes thats tough when its cold out. To add to what others have said, when you throw a single split on to burn the ash, use really dry wood that will buwn quick and hot, maybe seasoned pine or pallet wood. That should burn the ash quickly. I too think your wood might be part of the problem. The Oslo is a beast, but you might need a beast on steroids to heat over 3000 sq ft.

Good advice so far. What I would add is to not have to wait for the coals to burn down, I push them to the front of the stove and then put my highest BTU/biggest wood on top of them and in the front of the stove and lesser BTU/smaller wood to the back. What happens is I get everything to burn down much more evenly as the stuff in the back ends up burning about the same rate as the stuff in the front.

Try splitting a little bit of your wood into "planks" that are very thin, about an inch to inch and a half. These season quickly so they will reach their optimum moisture content more quickly and can be used to either assist in starting a new fire or covering the coals after they have been raked forward toward the ar intake. By covering the coals, you can hold in more of the heat from the burn and accelerate the burn process.

We had this problem when we first got this new stove but soon figured out the remedy. If we have been running the stove top temperature at over 500 (like now), then as soon as the temperature goes down to 450 (or sometimes as soon as the temperature starts to drop) we simply open the draft full right then. We have found that with the temperature at that point the firebox is either down to all coals or very close to that point.

By opening the draft full we are able to maintain that heat for quite some time. As the temperature drops, we do take a poker and rake through the coals to loosen them up so that air can circulate more in them which helps to burn them down faster. Yes, we also will rake the coals towards the front of the stove.

If ever we have a problem burning them down in this way, then we'll put a few pieces of kindling on top of the coals or a small split and let it burn. This will maintain the temperature even longer but will help burn down the coals.

One more trick is that once you are down to coals and the temperature is dropping, we've opened the firebox door just a crack to allow more air into the stove. It helps, but we always make sure someone is right there by the stove when we do this.