Sunday afternoon science - Thing 2

[Poindexter]

Using pretty much the same methods, freshly split face on the 6" scrap out of the middle of thing 2 was dry to the touch and lit both the 13 and 14 LEDs on the low range of my pin type moisture meter.

I did weigh the proposed kindling before I busted it up in small pieces. I came up with 5# 0.0ozs, but didn't fit all the proposed planer curlies into the stove. Also, Mrs. Poindexter was napping in front of the sliding glass door out onto the deck, so I didn' t break up the kindling as much, and I didn't check the stack plume at all.

I do have a hypothesis the stack plume becomes visible when the loading door is latched closed, as the A:F ratio is clearly under 50:1 with the door closed. I shall try to position a mirror out on the deck so I can see the stack outlet when Mrs. Poindexter is napping in the sun, we have some daylight now.

Outdoor ambient was +17dF today, not sure I recorded it last week.

T+16 seconds audible draft
T+74 seconds, door to cracked.
T +4:40 exhaust gas temp 200, loading door latched
T+ 11:00 flue gas temp 400, probe needle up off low stop
T +22:30, active zone, engaged, 600dF exhaust gas temp.

Going forward I am going to have to standardize my kindling. In spring shoulder season I will often be doing a cold start in the evening and rarely doing a hot reload in the morning. I brought in about a face cord of seasoned birch yesterday so I will have consistent fuel to play with.

About 8 more minutes to see where the load is 30 minutes after combustor engagement.

 

[Poindexter]

This pic is right around the 4:40 mark when I was ready to latch the loading door, flue gas temp was 200dF.

What I have found in the past is if I keep the loading door cracked open much after the flue gas probe hits 200, I am wasting fuel up the stack and not really heating the stove up. If I latch my loading door much before about 200dF flue indicated, there is some risk of my fire slowing down. When I latch my door right around 200dF, the flame doesn't stall and the steel starts heating up.

What I see in this pic is really good engagement between the flame of the kindling and the exposed face of the main fuel load piece on the left.

 

[Poindexter]

Also, just because I latch my loading door at 200dF flue gas doesn't mean you should. It works for me at my house with my install and my fuel blah blah blah. A place to start. If your fire is slowing way down, leave the drawer cracked a little longer.

 

[Poindexter]

30 minutes after engagement the combustor probe indicator is at least 1/3 of the way up the active zone, and my kindling hasn't burnt out because this fuel load is about the same MC as the kindling - everything is burning.

At this time I probably could throttle back, but Mrs. P is still napping in the sunshine and hasn't woken up cold. I have found facilitating good Sunday afternoon naps to be a good husband skill to have cultivated.

You will have to take my word for what I can see through the ash on the glass. I will pretty much be running on high intermittently for the rest of this season, should have the glass cleaned up in a few days.

 

[Poindexter]

I will make up a point to prepare a heartbreakingly ludicrous amount of kindling in the next few days. I propose about 2 ounces of small shavings for the small bit, and one piece of dry 2x4 (about a pound) about 12-16 inches long for the largest single piece. In between, some amount of pieces smaller than a pencil, maybe 6-8 ounces, thats 1#10, and then 3# 6 oz of pieces roughly the size of a 1x2 furring strip.

That should be plenty of small stuff to get the 1x2 going well. I have noticed furring strip between the upper and lower levels of the main fuel charge does really help out with horizontal flame propagation while the loading door is cracked.

 

[stoveliker]

This pic is right around the 4:40 mark when I was ready to latch the loading door, flue gas temp was 200dF.

What I have found in the past is if I keep the loading door cracked open much after the flue gas probe hits 200, I am wasting fuel up the stack and not really heating the stove up. If I latch my loading door much before about 200dF flue indicated, there is some risk of my fire slowing down. When I latch my door right around 200dF, the flame doesn't stall and the steel starts heating up.

What I see in this pic is really good engagement between the flame of the kindling and the exposed face of the main fuel load piece on the left.

View attachment 293824

I have the same experience; not sure about the 200 F, but I can sense a time when the stove warms up way faster without the fire slowing down too much if I close the door. (Thinking about it, I think it's the clanging sounds telling me the heat up speed.) There surely is an optimal time to close the door.

 

[Poindexter]

Yah, I think it varies a bit with fuel MC and outdoor conditions. Maybe 188-205 for me, my fuel is consistent, my ambient conditions are not. Other folks with different stack heights and blah blah blah blah may find different flue gas temps for sure.

I do also associate the bang/clang noises with the stove heating up, but generally have the loading door latched shut before they start.

I am pretty hot to get a mirror rigged out on my deck so I can see the chimney top from indoors. Latch the door, crack the door, latch the door crack the door. I "feel" pretty good that latching the loading door is where the visible plume starts, but I got nothing for data, today.

 

[Poindexter]

FWIW Doug Fir does not burn the same as White Spruce. I kinda like Doug Fir as a fuel for shoulder season, though it is awfully expensive for me as milled s4s S-Grn and shipped from the lower 48.

If you are used to, accustomed to, Doug Fir; White Spruce will burn out hot and fast while you go pee. Relatively. Not quite that fast in reality, but DF at 13% has a much longer coaling stage than white sprue at 13%. Like 90 minutes versus 30 minutes.

 

[Poindexter]

I will go look for a bag of hickory in the BBQ section at the home store this week. The wood stove sized splits.

 

[stoveliker]

I do also associate the bang/clang noises with the stove heating up, but generally have the loading door latched shut before they start.

Yes; the sounds after latching tell me if I timed it right.