Questions about my fermentor build

I getting the plan together to build a fermenting chamber and I have some questions about it. I'm planning to use an old window AC I have in the shed. I want to use this foam insulation:

http://www.homedepot.com/p/R-Tech-2-in-x-4-ft-x-8-ft-R-7-7-Rigid-Foam-Insulation-310891/202532856

Idk if there is any reason I mostly see everyone using the purple/pink stuff?

And I'm wondering about the bottom of the fermenting chamber. Do most people set a fermentor right on the foam bottom? I was thinking of putting something, mostly likely plywood over the foam on the bottom. I'm not sure how strong the foam is going to be with 3-4 fermentors in there.

Is there any need to add some sort of barrier, ie spraying something over the foam insulation or do most just leave it as is?

The window AC is digital so is there going to be a need for a temperature control?

Thanks for any help

 

Anyone?

 

Insulation is insulation. Since it's rigid foam it should work fine. If it were spun fiberglas it might be a different deal (in addition to being much harder to get to work), but sealing it isn't as important--it's its own vapor barrier.

I agree about the plywood to sit the fermenters on--in fact, you may want to create some "joists" in between which you use your insulation, and which will support the plywood somewhat better. Either 2x2s or 2x4s would work fine.

That the air conditioner is digital is less important than how it controls temperature. You might consider a temperature control like an STC-1000 which will turn the air conditioner on and off for you.

One consideration: air conditioners create condensation moisture--it will drip in other words, as it pulls moisture out of the air. You'll need to be sure you have a way to contain that.

 

So inside the chamber something needs to be done to control the moisture. Any suggestions?

I pulled apart the AC today to see about putting a STC or something similar on it. That's another thread...

Would having a space heater in there help with moisture or maybe a small hole for it to go out of?

And thank you for finally answering

 

I used the high performance pink high density foam in my chamber, I taped all my seams with silver duct tape and did use plywood on the floor. On thing that happened is I had a major amount of off gasses that were very nasty. I tried washing it with no effect. It took about a month to dissipate.

 

Gas' from what or where?

 

How are you planning on making this work? If you're setting the AC up on the "wall" of your fermentation chamber, it should automatically pull moisture out--that's what the dripping is from the AC. Most refrigeration systems do not have that--they simply have a cooled chamber in which moist air condenses and thus creates water/moisture.

Perhaps you could explain in a little more detail how you're planning on using the air conditioner?

 

This is the basis of my ideas

View attachment 1453084402849.jpg

View attachment 1453084413591.jpg

 

OK, that's about what I thought. If you have the chamber sealed to the air conditioner and it's pulling moisture out of the air, you shouldn't have moisture problems in the chamber.

However, w/ the setup above, I'm wondering where that condensation moisture is going to go. Is it dripping into a pan external to the insulated chamber, as some refrigerators have a pan on the bottom of the refrigerator from which moisture can evaporate?

 

I'm not sure, but now after talking with you I'm thinking about just having the AC off the side, more like a wall unit AC. I've seen some builds like that. All this is going to have to wait now anyways, the shed is going to need to be rebuild first! 😭

 

Boo, The foam insulation emits fumes in a closed space. In my case, I don't know if I had a reaction with something else but is was real strong. I am looking to add a layer of thin plywood to cover the foam. When my chamber is not in use, I open the door and let it air / dry out. Good build.

 

What type/brand did you use? And is that ALL foam insulation? I've never heard that before

 

An air conditioner is just a heat pump, all it can do is move heat from the evaporator to the condenser... in the above image the condenser is located within the cabinet. So all the heat removed from the chamber ends up inside of the cabinet, if you want to enclose it i'd put a vent fan pushing out from the enclosed area.

 

Lord knows I have an old computer case fan or 6 laying around my wife would like to see me do something with other then collect dust

 

If you go that route you can get a floor HVAC cover to go over the fan, the right style looks "in place"

 

Any foam insulation will what they call, Off Gas, It is a petro chemical product. When used in residential applications, it needs to be covered. The fumes will diminish over time but it can be bad. If it gets hot or is exposed to some chemicals the fumes can be even worse. Ihave had my chamber running for about two years and now there really isn't a problem. Oh, I used the Dow hi performance ridged foam, 1 inch thick.

 

Hi, I built the black cabinet above. If it helps, the evaporator is a closed system on this AC. air comes in through the bottom front, and out through the top front. that is the only part in the insulated cabinet. The condenser, compressor, and fan motor are completely outside of the insulated cabinet. The only moisture in the cabinet is what comes in when you open the door. I use a rechargeable Eva-Dry to catch that.

 

What I meant was that the heat has to be rejected to somewhere, in this case it's getting rejected outside of the temp controlled chamber but inside the cabinet where the rest of the unit is. If it works it works, but I would add a fan or at least a vent to allow the rejected heat to get outside of the cabinet.

 

All good.. I guess this is a good example as to why I should do a build thread.

The AC side and back third of the cabinet is open to vent into the garage..

 

I figured you did!! (because it was working!) Just didn't want anyone to copy you and not vent

 

I loved this idea! The fact that your on the east coast of Florida and I'm on the west helped me think I can make this work. We had to rebuild the shed first so I have to put this idea on hold for now. When I get everything together I'll post some pictures.