Ack!! Black mold in my kilns. Spock to the bridge immediately!

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Poindexter

Minister of Fire
Jun 28, 2014
3,161
Fairbanks, Alaska
WTFBBQ? O!

We have had another relatively mild winter, it is March and I am working on burning the first half of my fourth cord like I live in Arkansas or Missouri.

I started the season back in I guess August 2019 and have burnt three cords out of one convective kiln. Just to keep apples to apples with my previous threads, I have built floor modules each six or eight feet long with wood, but when I put the plastic on I connect two or three modules into a single convective unit.

For all y'all nit pickers I burnt three cords out of modules six, seven and eight this season, convective unit three, and it was beautiful, seasoned one summer. I have been burning out of my kilns since autumn 2016 and every split, every single split, was ready for home focused magazine cover. Better Homes, Family Circle, Architectural Digest, come on down. The first three cords I burnt this year out of module three, same.

I got into unit two, modules 3-4-5 (the ones with the profane names wile I was working out my design), black mold. Not a ton, but some. This was seasoned two summers. I did have some hornets in there in early summer 2019, but once the dry bulb temp in there got high enough they moved out. This three cord load was at 13% MC going onto Sept 2019, with some dead hornets and some dead spruce beetles.

How the blistering barnacles did I have black mold growing on this in Feb 2020?

And another thing, unit one, modules one and two is also showing black mold or fungus or tiny tiny mushrooms. All I can see with my bifocals is black dots. I loaded this one in April 2019, seasoned one summer. I put my best stuff in there, and it gets the best solar exposure. It is the one closest to the street. If Love INC calls again, these are the two cords to give away. Just beautiful stuff in there. I did Chihuahua spruce in there for a couple years, the kind of splits with no bark. They were especially photogenic.

Love INC didn't call this year, so I offered it at cost of green delivered splits to a guy at my church who bought a new house with a wood stove in it. He is pulling out of it one Tundra at a time, the first half was ready for the cover of a magazine, but now it is showing black spots too.

I don't get it. I am truly at a loss. I understand every surface on Earth has mold and fungus spores on it, but in high temps with low humidity they don't proliferate. They don't care for low temps either. Mine are proliferating. And where the heck is all the moisture coming from on the inside of my kiln membranes, it's frreaking 3 below this minute. My highest daytime high recently has been in something like +2 or +3 dF, but I was finding black mold in unit two with daytime highs around -20dF.

I see +/- 60 dF of solar gain at the height of summer, and breathing inside module one unit one this afternoon I was seeing my breath with every exhale at -3dF ambient .with 63% RH and dewpoint of -12 dF. It was definitely below freezing inside 1-1 even with solar gain.

The only hypothesis I have so far is I may have developed a temperatrue tolerant microorganism inside my kilns. Once all the kilns are empty I could take off the plastic membranes, concrobium the beejeezus out of everything left and start over with fresh splits and fresh membrane.

Open to SWAGs, I got nothing on this one.

The pics are the frozen condensate inside unit two, and the black mold on the splits inside unit two.

20200302_175356[1].jpg20200302_175417[1].jpg
 
I stuck a homeowner grade weather sensor inside 1-1 today, the one that was pretty last month and is showing black spots now. Ambient at the NOAA station about half a mile from my house was -9 dF with 69% RH.

I think my sensors are only rated down to +20dF, but after 30 minutes out there I was reading +21dF @ 13% RH, after 45 minutes I was seeing +9dF at 14% RH.

If I trust the +9dF later reading, RH should have been about 35%. If I trust the later 14% RH reading temp inside 1-1 should have been ~ +36dF.

None of these reading indicate mold growth should be an issue.

I guess I will look for a outdoor thermometer rated down to at least -40dF tomorrow to get an accurate dry bulb temp.

Stumped I am. Actually, I have room in there to sling a psychrometer just now... I wonder if those work below zero dF? I'll get two thermometers.
 
Well harumph. I found one online conversion table to use a regular psychrometer at below freezing temps, but it only reaches down to -20C, about -4dF, so i will have to wait for it to warm up a little bit out there.

I also remembered this from 23 months ago.

https://www.hearth.com/talk/threads/experience-based-solar-kiln-operation.167843/#post-2257369

That SOB #5, pictured on the right in the linked post is part of unit two that came up moldy this winter. The stuff on the left in module six (unit three) was only seasoned one year and looked great when I was burning it.

So where did all that condensation come from inside #5? Imma put my boots on and go look. And I got nothing, I did add a contact to my phone, UAF atmospheric sciences. Maybe I can convince a grad student with better instruments to come over if I offer beer and BBQ.

Also, the wireless sensor I had out in the kiln is rated to -40dF, doubt the batteries are. I will leave it out there a bit longer tomorrow.
https://www.acurite.com/shop-all/ho...ti-sensor-display-with-3-outdoor-sensors.html . It corrected from believable stove room readings to believable garage readings in about 15 minutes after I moved it to the garage.
 
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Would this work? I've been using one and it appears quite accurate when compared to another calibrated thermo/hygro. Good from -40 to +185 F.
 
So far I have called the Atmospheric Sciences department at my local U trying to entice a grad student on site with BBQ and beer. No dice, they gave my contact info to my local extension agent who has not yet called. I think today I will call my local extension office today...
 
So far I have called the Atmospheric Sciences department at my local U trying to entice a grad student on site with BBQ and beer. No dice...
BBQ and beer loses some of it’s usual appeal at -20dF.
 
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Everything loses its appeal at -20, except maybe making and sitting around a fire in a wood stove. ;lol
 
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Nothing useful to add here...title just made me chuckle... ;lol
 
My best guess is that you're getting bad data from your instruments. You got mold, try increasing ventilation and monitor progress.

An entertaining read, either way.
 
Do they have any shrinks in Fairbanks?
 
There are shrinks in Fairbanks. The best one had an affair and a messy divorce and moved to a large state in the lower 48 where one in six americans already live.

If you like the movie Chef enough to buy the DVD you get bonus features of John Favreau making a grilled cheese sandwich. If you like it a bit more you might buy the soundtrack as .mp3 and listen to low quality music in all manner of portable devices. If you channel that passion as a serious hobby you might buy the soundtrack as .wav files on physical media and find recipes on the dust jacket. Maybe. The .wavs can be cranked hard enough to scare the cat.

I remember when a grad student in a hard science like math or physics could be hired for a half day, worked like a slave, and paid with one sixxeer of imported beer, a delivered pizza and a twenty dollar bill. They would beg to come back again next time the lawn needed mowing. 38 years ago I first asked if I was old enough to be a curmudgeon and I am about done asking permission. I am going to have someone who knows more about cold weather water vapor transport than me and a cold weather microbiologist on my property this month even if I have to make 3 dozen cubano sandwiches and deliver them.

Instead of haggis in the fire, the shoulder is in the brine.. After brine and marinade I will smoke it on hickory Saturday. I will also be smoking a ham on cherry Saturday, my ham glaze is frankly epic. Monday I will wander on to campus with some, umm, treats.

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It was a lot less than 34 years ago that I was a grad student working on my Ph.D. in engineering. I was the only American citizen Ph.D. candidate in the rather sizable EE graduate program, and one of only a small handful in all of their engineering graduate programs combined, despite being one of America’s more prestigious universities.

What I’m saying is that, if you want to bribe today’s Ph.D. students with food, you’d better learn to cook Chinese.
 
Rats. Local university campus is closed (spring break extended) at least to the end of March. First two cases of corona virus were confirmed in Fairbanks yesterday. The good news is I have a bunch of Cubano sandwiches to eat.