Woodstock Absolute Steel - How to burn hot?

Thanks for the tips, Qyota. I've been reluctant to try engaging the cat with the air wide open, because I thought I read something in the manual about not setting it at 4 with the cat on. But maybe that's the key to push beyond 400, and not really a concern if STT isn't getting near "overfired" temps anyway.

I'm also curious how the outdoor air kit works. Assuming there's no negative pressure situation, does the kit increase the volume or alter the pattern of airflow through the stove, similar to how cracking the door open does? And if so, is it possible to open the external air inlet without actually connecting it to a conduit from the outside?

 

On the AS the stove connector to outdoor air kit is the only way for air to get into the stove when the door is closed, even if you don’t have an OAK.

 

I suspect a weak draft, especially if its performance is outside-temperature dependent. Does your chimney meet minimum for the stove?

 

With marginal wood, leave the door cracked while you get up to a temp where you can light the cat. Then, you can still have the door cracked while the cat is engaged, let it get the stove up to 500ish and then shut the door. Then you can start dialing the air back from there.

It's not as easy with less than optimal wood, so it will take you extra work.

 

Thanks, Savage! I've been hesitant to contact Woodstock until I can pick up some kiln dry wood to try out, as I know my current wood is substandard at best.

Definitely feels like there's an air intake (or possibly egress) element to this too. With barely seasoned, snow-dampened wood last winter, I could throw a few sticks on a hot coal bed in my old stove, close the door once they started burning, and the stove would soon overfire if I didn't reduce the damper setting. With this stove, I can get a roaring tornado of fire going with the door cracked, but the STT doesn't get above 450 no matter how long I run it this way. Once I close the door, with air control lever at 4, bypass open or closed, the flames quickly die out and the STT starts falling back into the 300s. I can set the air lever to somewhere between 1 and 2, engage the cat, and at this point the stove will cruise along with STT in the low 300s, stovepipe temp around 230 or so, and heat but no visible smoke coming out the chimney top. But the STT and stovepipe temps gradually decline, and within a couple hours or so, I need to open it back up, stir the coals, and let it breathe for a bit to reignite what are often a couple large carbonized logs and get the cat temp back up to cruising speed.

Until I can run it with 100% kiln dried wood, though, I won't rule out the possibility that this is all due to "user error"!

 

Can you describe your flue pipe configuration for us?

 

I've got a 6" 22 gauge single-wall adjustable 90 degree elbow bent into an S-shape connecting the rear vent on the stove to the thimble on the chimney behind it, about 2" higher than the stove's vent collar. The chimney is inside the house, some kind of lined masonry, I'd guess 18' - 22' tall, with a cap on top. Meets the clearances for surrounding obstructions above the roofline specified in the stove manual. Worked fine with the old stove, and sweep didn't note any issues with it when cleaning it out this summer, so I don't know much more about it.

 

Any other inlets to the flu other than a clean out door? Furnace, etc? Probably not, but I still see it a lot.

 

Your wood is too wet.
Do you bring wood in days in advance to warm up before burning? This makes a huge difference!
This rainy damp weather pattern we're stuck in makes it hard to get a fire going.
Also, filling the firebox on the IS makes it easier and faster to get a good fire going.

 

My firewood wood is definitely too wet, but I was having the same issues even with super-dry Canawick and Lewis bricks only.

Something changed last night, and I'm not sure if it was cooler, drier air outside, or maybe that I've crossed some "break-in time" threshold, but my small load of only Canawick bricks ignited and got the temperature rising a lot faster than before. Within about 30 minutes, I was able to close the door and bypass, dial the air down to .75, and the cat was off and running until it burned down to ash and a few small coals.

This morning I loaded up a few more Canawick bricks on top of the coals and topped those with a bunch of thick splits of my under-seasoned firewood, and the STT and pipe temps quickly shot above 500 (as hot as I've seen them yet!), even as I could hear the moisture hissing out of the splits. After closing the door and letting the roaring fire drive some more moisture out of the splits, I closed the bypass, dialed the air down to 3, and then .75 a few minutes later, and it's been smooth sailing since then!

Would a drop from 30s and wet to 20s and dry weather make this much difference? Or is there some validity to my break-in idea? Either way, it's like night and day, even with less than optimal wood. And the dog approves!

 

Only point on the break-in idea, is that the cats can be hyperactive when new. And after a little while burning they can settle in. I think the temperature drop has more of a point as it probably in creased your draft.

 

Well I should be good for the next few months then. If it continues to struggle when the weather turns warm and wet, I'll talk to the chimney guys in the off-season about how to increase the draft.

 

The weather is the biggest factor.
When the cold dry air moves in from the north, it's like you got a whole different stove.
I had smoke pouring out of every crack in my stove Sunday afternoon on a cold start. I had a window and door open and ended up sticking a propane torch in the clean out to get the down draft to stop.
It was 50 degrees Sunday and partly sunny...

 

Did you reload them on a bed of hot coals or was this on a cold start?
What was the weather like those days?
Did you fill the firebox with bricks and splits?

 

I'd definitely done it from a cold start, can't remember if I'd also tried it on a hot bed with only dry Canawick bricks or not. But last night and this morning it lit and fired up easily with barely any coals remaining, and this morning that was even with a bunch of my under-seasoned logs on top of the bricks. Just took a little longer to drive the moisture out of them before I was able to close up and turn down the stove, which I'd expect to be the case.

 

Great! Sounds like your getting the stove dialed in.
I'm thinking the weather change is making the difference.

I like to let all the wood char before closing the bypass. Then I'll let the air wide open till about 400 degrees SST. (sometimes higher but it fires the new cat off pretty quick ).
I can usually set the air pretty soon after that.
I find this all happens faster with a full load of wood.

 

I'm thinking it's the weather too. Temps outside are warming back up this afternoon, and my STT is drifting down no matter where I set the air intake.

 

I feel obligated to chime in here. I do not have a woodstock stove. However, I do have experience with the sawdust brick fuel you keep mentioning. When we first installed our stove 5 seasons ago I was short on firewood so I purchased a pallet of those sawdust bricks. In my Drolet Austral I had trouble getting those to burn very well. For whatever reason my stove just didn't like them. My theory was they are simply too densely packed. I suspect this is a fuel problem. How are you stacking the bricks in your stove? Definitely find some known dry quality fuel and see if that helps.

 

That marginal wood of yours, can you get it somewhere that it can stay dry? I had a lot of moisture under the bark, and in the sap wood when I first loaded my bin due to the extremely wet summer we had. Its barely been above 40 since I brought it all onto my enclosed porch, but it all dried out. It's very rare that I am finding a hissing split now.