Keep a layer of Ashes on the firebox’s floor or not?

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myth83

New Member
Sep 20, 2019
41
Germany
Good day everyone,

I was wondering the other night, about the tip about keeping an inch or so of ashes from previous burns on the stove‘s floor and not completely vacuum it out when cleaning the firebox - for the benefit of better and hotter burns and keeping the firebox floor for longer.

How real is this method?

Some say it is important when cleaning the firebox to suck out all of the ashes.

My insert had no ashtray and no grate, it is a cast iron Jotul insert (I400 Harmony) that has a cast iron floor and firebricks are only attached to the firebox walls.

1. Should I maintain a layer of ashes? Should I not?

2. Are there benefits in doing so? Or negatives?

3. Would a grate help keep the cast iron firebox floor from overheating? Does it make sense at all or should I not worry?

Thanks for any tips :)
 
Good day everyone,

I was wondering the other night, about the tip about keeping an inch or so of ashes from previous burns on the stove‘s floor and not completely vacuum it out when cleaning the firebox - for the benefit of better and hotter burns and keeping the firebox floor for longer.

How real is this method?

Some say it is important when cleaning the firebox to suck out all of the ashes.

My insert had no ashtray and no grate, it is a cast iron Jotul insert (I400 Harmony) that has a cast iron floor and firebricks are only attached to the firebox walls.

1. Should I maintain a layer of ashes? Should I not?

2. Are there benefits in doing so? Or negatives?

3. Would a grate help keep the cast iron firebox floor from overheating? Does it make sense at all or should I not worry?

Thanks for any tips :)
Yes leave some Ash on the floor. It helps maintain a good coal bed and protects the floor. No real downside unless you let it build up to much.
 
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Definitely a lot easier starting a fire with about an inch of ashes compared to none. The ashes seem to insulate the coals.

Sent from my SM-G950U using Tapatalk
 
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Notes taken, thank you all for your replies, I highly appreciate it.

So no need to add a grate? Just leave a layer of ashes?
 
Notes taken, thank you all for your replies, I highly appreciate it.

So no need to add a grate? Just leave a layer of ashes?
No absolutely no grate
 
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I have the option of using a grate and ash pan, or letting it build up. One thing to notice is that ash is very compressible. What seems to be a layer of thick fluff from an overnight burn, turns out to be a fraction of an inch layer when allowed to build up and compress down. Depending on the wood, could go many days or weeks, burning 24-7, and still only have several inches built up.
As far as is it beneficial to leave a layer of ash - it does insulate, keeps coals active longer, reduces the work load of cleaning maintaining. Try leaving it for a while, then not, and notice the difference, it won't hurt.
 
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I only vacuum once per year at the end of the season. Otherwise a scrape the ash out to the floor. No need to be too worried about getting it all since you will just turn around and burn more wood anyway.

Just do an experiment. You won't have any ash for the first few fires anyway. Then see how much more you like it as the ash bed gets deeper. You can then clean it all out and see how much worse the fire burns.

The trouble with too much ash is that it takes away from the fuel capacity of your firebox. Then eventually it can even spill out of the door!
 
Some say it is important when cleaning the firebox to suck out all of the ashes.

Nobody says that.
A time where I think a thorough cleaning would be important is when shutting down for the summer. Wet humid ash can be corrosive. I wire brush and vac as much as I can get at in the spring. Otherwise, vac it, and it only would stay cleaned for, what, a few minutes.
 
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Thank you all for the informative replies, so to summarize what I have understood:

1. thorough the heating season, a layer of an inch or so of ashes should be maintained to help insulate the firebox floor and keep the coals burn hotter and longer.

2. between burns, scoop out some of the ash bed to level it, but not too much.

3. when the heating season is over, or in periods where the stove/fireplace will not be used for a prolonged amount of time (e.g. a two week holiday) - make a complete cleanup including sucking out the ashes to avoid corrosion.
 
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Like most everyone else the only time I completely clean out the ashes is at the end of the burning season.

And like most everyone else I wholeheartedly agree that you want to have a bed of ashes in the stove as it offers the stove some insulation, helps preserve coals, etc. . . . as long as it isn't so deep that there is no room for wood. I like an inch or two in the stove and generally after a night of burning will stir the ashes and coals, allowing the ash to drop down into the ash pan . . . and then I reload and go.
 
A time where I think a thorough cleaning would be important is when shutting down for the summer. Wet humid ash can be corrosive. I wire brush and vac as much as I can get at in the spring. Otherwise, vac it, and it only would stay cleaned for, what, a few minutes.

Now that's a first -I never heard of anybody doing that.
 
Now that's a first -I never heard of anybody doing that.
On mine there is an ash pan and the door that closes in front of it. Crust, ash and creosote can build up behind the pan, making it less likely to get the door closed tight. A poorly fitting ash door is a serious situation. And it's all a tight fit to begin with. Otherwise, maybe it's not needed, but doesn't take any more time really since I'm scraping clean the ash pan area anyway, plus the stove does look clean inside for having been in use for 10yrs. Some others look like a wreck, same model, same age. Also maybe it's just me and my way. I like having things cleaned up for the summer, start fresh in the fall with a new stove again. Other guys on here have never cleaned out their stoves except to shovel some ash. To each their own.
 
What does the owner's manual state?

Mine has:

1. "Whenever ashes get 3 to 4 inches deep in your firebox or ash pan, and when the fire has burned down and cooled, remove excess ashes. Leave an ash bed approximately 1 inch deep on the firebox bottom to help maintain a hot charcoal bed."

It soon follows this with slightely different instructions.

"Ash removal is not required once it builds up. 1/2" to 1" of ash may be desirable because it slows the burn rate. Generally, remove ash once it has built up over 1"."

2. Fire burns better.

3. No grate. I have fire bricks on the floor anyway.

I let the ash build up and remove some when high, always leaving some ash in the bottom. Complete cleaning removing firebrick lining, air tubes, and vacuuming when I clean at year end.
 
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when the heating season is over, or in periods where the stove/fireplace will not be used for a prolonged amount of time (e.g. a two week holiday) - make a complete cleanup including sucking out the ashes to avoid corrosion.

You've got it except this part. Only worry about full cleaning at the end of the season. A couple weeks in the winter is not likely to cause corrosion due to the low humidity during the heating season.
 
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I dont think it really matters much from a physical standpoint.. I dont vac it clean for the simple reason that I dont like wasted efforts the older I get. Vacuuming it clean might serve one's anal retentiveness but it's meaningless otherwise. I say do whatever turns you on (or pleases a picky wife).
 
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I clean out the ash in summer or early fall when I get around to it. It's sitting on firebrick. I'm not concerned about corrosion there and we have dry summers.
 
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I dont think it really matters much from a physical standpoint.. I dont vac it clean for the simple reason that I dont like wasted efforts the older I get. Vacuuming it clean might serve one's anal retentiveness but it's meaningless otherwise. I say do whatever turns you on (or pleases a picky wife).

I would have to disagree, I certainly get a noticeably better fire that heats up quicker when there is a layer of ash on the bottom. I have noticed this in regular fireplaces as well. Its nothing major, and after one fire you have that layer anyway, but for that first fire without a layer of ashes, the stove is slower to heat up.
 
I would have to disagree, I certainly get a noticeably better fire that heats up quicker when there is a layer of ash on the bottom. I have noticed this in regular fireplaces as well. Its nothing major, and after one fire you have that layer anyway, but for that first fire without a layer of ashes, the stove is slower to heat up.
I think Ludlow is talking about cleaning to an anal retentive level at the end of a buring season - not normal cleanings when the stove is in use. Most would agree leaving some ash for the next fire is a good thing.

I think wire brushing is a bit excessive unless its to make sure a door closes tight.
 
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Even end of year cleaning I leave an inch of ash, much better fire with it than not.
 
Even end of year cleaning I leave an inch of ash, much better fire with it than not.

For those of us with bottom bricks, it is nice to inspect those bottom bricks and be sure that the ash drop mechanism is fully functional once per year anyway.
 
Yes, I like to clean the stove out once a year for inspection purposes, though I leave the ash dump hole full. Haven't used it more than a few times and that was 10 yrs ago.