Coal bed size on reload

[weee123]

So I’m wondering if people can share pics of how big of a coal bed they have when they reload their stove.

I reloaded my stove for the overnight burn last night on an even bed of hot coals about an inch and a half thick. The wood took off right away as I was loading it in N/S and was burning good. After I had the air shut off and settled and cruising at about 630 at the outlet for 15-20 minutes figured I was good to go to bed. Right before hitting the hay I decided to recheck it and saw that it had gotten way hot up to 750 and climbing. Felt uncomfortable with how hot that was and put a fan at the stove and opened the door to cool it down and a shovel of ash to get the temps down.

So I figure if I have a bed of coals like that I’m just going to have to do an e/w load instead of trying to do a n/s. Also how hot do you guys feel comfortable getting your stoves temps up to? My stove lists 840 as an overfire but I don't know where at on the stove that temp is measured. Near the front of the stove top was around 600 and climbing same with near the door, but near that outlet was getting screaming hot like I said about 750 and climbing.

 

[weee123]

Also to add I just replaced my door gasket and it burns like a completely different stove now and get much better burn times.

 

[Ctwoodtick]

When it’s cold and you need the heat, I load up on whatever size coal bed I have. If it get big enough to restrict the amount of wood I can put in, I do the trick where I rake the coals forward and put a piece of kindling on top of the coals and open the air all the way up. That burns the coals down nicely after a couple cycles of that.

 

[BigJ273]

Maybe reduce the load size to keep the temps down

 

[EbS-P]

How soon after reloading was air turned down all the way?

 

[weee123]

Maybe reduce the load size to keep the temps down

It’s for an overnight load and was a little over 2/3 full.

How soon after reloading was air turned down all the way?

Maybe 10-15 minutes?

 

[EbS-P]

In my experience hit reloads need packed tight (full load or not and the air almost immediately turned down. This is where flue gas temps are the most useful. You can see immediately how the air setting change temps and are much less likely to over shoot.

 

[weee123]

I was trying to go by my flue temps but it took a little bit for them to hit 300 with the ir gun which is what I usually shoot for before I start dampering down

 

[stoveliker]

This was a bit early for me. Could have simmered another hour or two at low output on top of the 20 hrs I had already. So this is a bit much coals for me.

I raked these into a log shape n/s in the center before I reloaded.

 

[weee123]

Wow that’s not much coals at all compared to what I had

 

[stoveliker]

This had been a mix of red oak and pine. Burning mode matters too in how many coals one gets. Burning at higher rates increases how much coals are left when the need for heat dictates that a reload is needed.

 

[weee123]

I always try to burn on the lowest rate possible. As soon as I can turn the air all the way off without smoldering I do so. Sometimes I turn it down a little too early and it smolders then have to crack it open a hair and wait for it to get sufficiently hot before I turn it down again.

 

[stoveliker]

In the end the burn rate is dictated by how much heat you need, within the range of capability of the stove.

Wetter wood also can give more coals. My oak was 16 pct or so and my pine even lower.

The amount in the pic is more than my normal situation at reload in shoulder seasons. Mid winter I have more coals as I need more heat than the remnants can provide. For dry wood though, less.coals than the pic is still more than enough for a quick relight; often I have them burning quite well before the door is closed.

Putting a 1" piece of dry wood on a line of coals near the door works great to burn them down once their amount interferes with a reload size.

 

[weee123]

So when you say burn rate are you talking about, what air setting you have it on? Or burn time wise before reload?

 

[stoveliker]

Air settings are not comparable between stoves (hole sizes and air flow impedance will be different) and even for the same stove on different chimney systems (flow is determined by draft) .

Burn times depend on fuel load and all of the above


So comparing that doesn't make sense imo.

But yes, burn rate is the speed with which you consume a load.

 

[weee123]

Thanks for clearing that up for me

 

[EbS-P]

I was trying to go by my flue temps but it took a little bit for them to hit 300 with the ir gun which is what I usually shoot for before I start dampering down

750 flue temps might just be normal during the peak of the burn. I can’t get my insert below 800 at the appliance adapter. Efficient no dangerous no.

 

[weee123]

The 750 temp is stove top near the flue outlet not the flue temp itself. I usually run around 600-650 flue temps occasionally hitting 700-750. I’m not too worried about those temps just the high stove top temps ive been seeing.
What do you mean by appliance adapter? The area of the stove where the flue enters?

 

[Todd]

When it’s cold and you need the heat, I load up on whatever size coal bed I have. If it get big enough to restrict the amount of wood I can put in, I do the trick where I rake the coals forward and put a piece of kindling on top of the coals and open the air all the way up. That burns the coals down nicely after a couple cycles of that.

This! Raking the coals forward makes a huge difference with a non cat stove. If a large coal bed is spread evenly around it can cause a new reload to off gas much quicker or all at once. Raking coals to front will produce a more controlled front to back cigar type burn.

 

[stoveliker]

Same for a cat stove (at least ones where the air comes in over the window in front).

 

[weee123]

Ahh ok that makes sense thanks for that tip

 

[Draughts15]

I'm still perfecting a safe/unstressful reload on a coal bed, but generally my flue temp is around 350-375 max. Like others have said, I rake the coals to the front and by the time the fire really takes off most of the coals have burnt down. Sometimes I'll leave the coal bed as is and throw a couple smaller pieces or a very large split to have coals several hours later. I also found turning the air down very quickly helps in preventing a potential overfire.

 

[weee123]

Are you guys concerned with how hot the stove top gets near the flue or just near the front of the stove?

 

[begreen]

This was a bit early for me. Could have simmered another hour or two at low output on top of the 20 hrs I had already. So this is a bit much coals for me.

I raked these into a log shape n/s in the center before I reloaded.

View attachment 303589

That's about what I burn down to too. Reloading on too large of a coal bed will cause a very rapid outgassing of the firewood load, spiking the stove temp and/or allowing for a lot of wasted heat to go up the chimney as smoke when it overwhelms the secondary burn system or the catalyst.

In order to burn down a large coal bed I open up the air at least 50% and put on a couple 2" splits on top. That provides room heat while burning down the coal bed.

 

[BillBurns]

I play it safe and wait til morning, then get it going again. I dont like the fact that there is a fire in my house while Im sleeping. Thats just me tho. Id like to wake u to a warmer house, but I use oil for backup. Overnights and emergencies . Pretty funny...oil used to be .99 a gallon, back "in the day".