Solar Kiln Advice

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Mike.O

Burning Hunk
Dec 20, 2017
166
..
Hi guys,

I'm trying to get ahead of this wood game and stay ahead. Been in our house 3 years and finally catching up.
Burn about 4-5 cord a year and maybe one more for maple syrup.

Yesterday, I finished my covering / "solar kiln". It's 12'x20' with about 5 cord inside. All rows spaced 1' apart. It built some roof trusses and utilized the stacks as the "walls"

It's been cloudy and crappy here so I havn't been able to see how it performs. I crawled under today and HOLY MOISTURE on the ceiling.

Where is the best place to vent. Cut two flap vents in the gable? What size? I don't want to lose too much heat, but I want to get the moisture out.

I know the front right corner the poly is too tight to the wood. I'm going to try to space that off a bit this week, so don't kill me on that!!

Thanks!

[Hearth.com] Solar Kiln Advice
 
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My kiln is different than yours it is more a T-Pee with the vent at the highest point
and air intake below the pallets works really well
With yours I would be temped to vent it out the gable ends using a fan on a timer
don't forget you need to replace vented air
 
My kiln is different than yours it is more a T-Pee with the vent at the highest point
and air intake below the pallets works really well
With yours I would be temped to vent it out the gable ends using a fan on a timer
don't forget you need to replace vented air
Thanks for the input. I'm pretty similar with my air intake on the bottom. I'm set up all on pallets and the poly mostly stops at the bottom 4" of stack.

I just cut +/- 1" by 18" slits in the top at the peaks at each end. It feels like a lot of air flowing out. Hope it wasn't too big and lets too much heat out.

Before I cut the slits, there was an incredible amount of water on the inside of the plastic. Hoping with some air flow this is minimized.
 
Your going to need to vent it at the top. Both gable ends would be the best and i would start about the size of a grapefruit on both ends. Do not cut the plastic out as you do not remove the plastic just cut a u shape. Moisture on the inside is not ideal. You want the moisture to vent out. You dont need a fan as the natural conviction will happen inside the kiln. I hope you allowed the wood to dry some.. theres a link in my signature that may help you with the kiln
 
Your going to need to vent it at the top. Both gable ends would be the best and i would start about the size of a grapefruit on both ends. Do not cut the plastic out as you do not remove the plastic just cut a u shape. Moisture on the inside is not ideal. You want the moisture to vent out. You dont need a fan as the natural conviction will happen inside the kiln. I hope you allowed the wood to some.. theres a link in my signature that may help you with the kiln
Thanks for the advice. I think my vents are too big and I cut them clean out, no flaps. Looks like ill be modifying that.

The wood was split in October and a little bit in December. So It had a little time to season. Some was wet from rain 2 days before I covered everything in the kiln.

I did see your article before I started and that is where I got the shrink wrap idea. It worked out great!

Will the condensation moisture on the roof eventually evaporate it self out?
 
Thanks for the advice. I think my vents are too big and I cut them clean out, no flaps. Looks like ill be modifying that.

The wood was split in October and a little bit in December. So It had a little time to season. Some was wet from rain 2 days before I covered everything in the kiln.

I did see your article before I started and that is where I got the shrink wrap idea. It worked out great!

Will the condensation moisture on the roof eventually evaporate it self out?

So what i do is i put an air probe in the kiln to see what the temps are on a sunny day. I base how big the vents should be on that temperature. If its to warm it means i can vent it more, to cool vent it less. Dont cut the plastic out, use a flap technique, you can duct tape it if it cools down or tou neet to make adjustments. There should be verry little to no condensation when the kiln is going..hope this helps
 
Where did you buy the plastic and how thick is it? I will be looking to make a small one to season a cord or so at a time. trying to keep it as cheap as possible
 
Where did you buy the plastic and how thick is it? I will be looking to make a small one to season a cord or so at a time. trying to keep it as cheap as possible


Go to any big box store.. 6mil clear plastic.... grab the 6 and not the thinner stuff.. thin stuff will not hold up for a long period ..
 
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Where did you buy the plastic and how thick is it? I will be looking to make a small one to season a cord or so at a time. trying to keep it as cheap as possible
Home Depot. 6 mil clear. 20'x100' was $100. I think the 10'x100' was close to $50.