Burnin' like a BK

[Ashful]

So, I had the stove going all weekend, outside temps Saturday being 28'F - 55'F, and Sunday 46'F - 73'F. Managed to maintain the stovetop at 200'F - 300'F around the clock for two days, only reloading once on Saturday and twice on Sunday. Enough coals were left from each load after 8 - 12 hours to light the next without rekindling. House temp stayed at 72'F - 73'F all day Saturday, and 73'F - 76'F all day Sunday. I would not have burned for myself Sunday, but my wife and ever-cold MIL were in the house, and I was outside working with my FIL.

Maybe not on-par with BK's best, but I suspect closer than I'd get with any modern non-cat. No? Maybe I'm getting the hang of this, after all.

 

[jeff_t]

Loaded up 6-7 med/large splits at 2am on Saturday. Stove was still warm last night. Luckily, it was windy when it was 70 outside yesterday. Stove was cold this morning, but there was a lot of embers when I shoveled out the ashes. Not enough to light a load, but it was 54 hours later.

You asked for it

 

[Ashful]

Oh, I knew that was coming.

Just the same, I'd like to hear from a non-cat burner who kept a stove going 12 hours on a warm day with 200'F - 300'F on the stovetop with one small load of wood, still having embers for a relight afterward.

 

[Todd]

Sounds like your getting the hang of it. We're you filling the stove full and maintaining those temps?

I don't think a non cat can do this with a full load but you can maintain those temps if you just reload a split or two every few hours.

 

[BrowningBAR]

Any smoke from the chimney? Do you have a cat probe in to see if the cat was engaged?

 

[BrowningBAR]

Sounds like your getting the hang of it. We're you filling the stove full and maintaining those temps?

I don't think a non cat can do this with a full load but you can maintain those temps if you just reload a split or two every few hours.

Joful is running the older F600 which is a cat stove.

 

[Ashful]

Hey BAR, I have two cat probes sitting on my desk, but haven't installed them in the stoves yet. It was daylight, so I could see the cat light off by watching the chimney. After each reload, the cat was a little sluggish to light at those low temps, but in each case it did shortly after closing the bypass damper. My proceedure was reload, run in bypass 5 - 15 minutes at wide open throttle (trying to get up to 300F stovetop), then close the bypass and wait for the smoke to disappear from the chimney before incrementally working the throttle down to 1/4 open.

Todd, I was not filling the stove full, but was still able to get 8 - 12 hours with coals for a relight on my smaller loads of 4 or 5 small/medium splits or branchwood rounds. My goal is to work as close as I can to a full load in all weather conditions, the way the BK guys do. My working theory is that this automatic thermostat on the BK's is very cool for maintaining a constant temperature, but is not the sole factor permitting very long burn times. In fact, I suspect that when going for min heat output / max burn time, that thermostat is probably not doing anything at all, just remaining in the most closed-off position all the time.

Right now, my poor chimney setup limits how far I can lower the throttle in warmer weather (backpuffing occurs at very slow burn rates). So, I do have to settle for smaller loads in warmer weather, keeping the throttle at least 1/4 open to prevent draft stalling. I'm hoping the insulated 6" liner I'll be installing in three weeks will get me further toward that goal.

 

[Todd]

I'm not exactly sure how the t-stat works but I know for me it is opening and closing at a setting of 1.5 giving me an easy 24 hours. I haven't had the need to go any lower. Proper draft and good wood is key for any cat stove to perform up to its potential.

 

[Ashful]

Proper draft and good wood is key for any cat stove to perform up to its potential.

I'm not in great shape on either of those factors, but working hard to correct both. Wood burned today was split last February, and my 13 feet of 8" clay tile in an exterior masonry chimney is soon to be stuffed with a 6" insulated liner.

 

[Todd]

I'm not in great shape on either of those factors, but working hard to correct both. Wood burned today was split last February, and my 13 feet of 8" clay tile in an exterior masonry chimney is soon to be stuffed with a 6" insulated liner.

That liner should make a huge improvement.

 

[jeff_t]

Well, with that chimney setup and questionable wood, I'd say you're doing quite well. I'll look forward to hear how you do next spring.

If I tried to burn a load of wet wood like I have been burning good stuff, I'm sure it would just go out. Not talking about fresh cut green wood, but I doubt if anything that was much over 20% would burn for two days.

 

[Highbeam]

My working theory is that this automatic thermostat on the BK's is very cool for maintaining a constant temperature, but is not the sole factor permitting very long burn times. In fact, I suspect that when going for min heat output / max burn time, that thermostat is probably not doing anything at all, just remaining in the most closed-off position all the time.

I think you're right Joful, especially with a strong draft, cold ambient temps, good wood, and the fans running, the stat shuts and stays shut at lower settings. Even on an ice cold stove, the stat slams shut at a setting above the minimum "normal" setting so you know the stat stays shut as the stove warms up.

If it's not the stat, then what magic allows the BK to burn for 24 hours effortlessly? Maybe you'll find out. Keep trying with your jotul, we like to see the improvement. Don't be discouraged by the ease at which the BK can do the same thing because as a side effect, we have to look at the ugly BK all the time. I know, I know, she has "personality".