Overboard fermentation chamber design. Need advice

Attached is a picture of rough design of how I want my fermentation chamber to turn out. It's based off the son of a fermentation chamber design, utilizing a full size Kenmore upright freezer as a source of cold air. I will have the freezer running normally, keeping my hops/grains cold, and probably at the bottom I will have a large water bath where you see the red 'f'. That f is for fan, which blows down the insulated pipe to a center pipe where the chambers can pull cold air in.

A few things to note:

Each chamber will have the eBay aquarium controller and a reptile ceramic light bulb for heating. The cold side of the temp controller will operated the fan labeled 'F' in red on the sketch.

I want to run thermowells in each carboy for accurate temperature monitoring, which means each chamber will be seperated by a few prices of insulation.

I am splitting the chambers up as well in hope I can do a lager in 1 or two, and ales in the other, also, I will be keeping the ales in one fermentation carboy to ferment and condition, this will allow me to keep each ale at a colder temp for aggressive fermentation, and warm it up afterwards. Same thing with the lagers, cold fermentation, diactyl rest, then I can rack.

I will keep the chambers as small as possible, I'm even thinking about having the ceiling short and having the airlock pop out of the top, so we are looking at a 15x15"ish by 24"ish space in each chamber.

I want ro do this mostly cause I thought it would be cool, and it would counter the stupid California weather we are having this year (100 one week, 55 the next) it also gets me out of SWMBO kitchen/closets.

Am anyone think the freezer water/ice bath wont be enough to supply cold air for lagering? In sure it will be fine for ales.

Am I insane and I should just make it one larger chamber and just either do ales or lagers?

Just looking for input.

Thanks,
Mike.

Can someone also tell me if the picture is large enough to see? I just did this while thing from my phone, lol.

Sweet idea. Note that with the fans not spinning, cold air will leak past them...

Why the water bath if you are basically doing a "forced air" design?

Pic is quite small...about the size of a small phone screen, but it is visible.

shortyjacobs said:

Sweet idea. Note that with the fans not spinning, cold air will leak past them....

Click to expand...

In front of each fan for the chamber will be one of those cheap plastic swing valves you can get at home depot. I think they are for dryers when they duct the exhaust to outside of the house, so nothing can get in. It won't be perfect, but again each chamber will have a heater.

shortyjacobs said:

Why the water bath if you are basically doing a "forced air" design?

Click to expand...

My theory is to actually have it be a block of ice with a channel cut in it that the main fan pulls from. The point being the freezer won't have to cycle as much.

shortyjacobs said:

Pic is quite small...about the size of a small phone screen, but it is visible.

Click to expand...

Thank you, I'll see what I can do about that.

Need return ducts?

phoenixs4r said:

In front of each fan for the chamber will be one of those cheap plastic swing valves you can get at home depot. I think they are for dryers when they duct the exhaust to outside of the house, so nothing can get in. It won't be perfect, but again each chamber will have a heater.

Click to expand...

Sounds good. I was thinking along the same lines.

phoenixs4r said:

My theory is to actually have it be a block of ice with a channel cut in it that the main fan pulls from. The point being the freezer won't have to cycle as much.

Click to expand...

I see. The channel will melt down, but I guess once it all puddles you can re-carve the channel.

AnOldUR said:

Need return ducts?

Click to expand...

Yeah, good point. If you had a return duct, so the cold air was constantly circulating through the "main line", it would make it easier for the spur ducts to pull off cold air for the chambers...

AnOldUR said:

Need return ducts?

Click to expand...

Possibly. I was thinking about adding something to each temperature controller to kick on the main fan when they need to kick on their idivdual chamber fan, but I think a return duct would be much simpler.

I think return ducts are going to be necessary for this one...and since you are going to have a return duct, I think the freezer is going to cycling alot anyway to cool that warm air coming in. I'm not sure the block of ice is going to get you anywhere (other than a mess), but I don't know.

Disclaimer: I'm not a big fan of these home-made ferm chamber contraptions. I think by the time you are done spending the money on lumber, parts, etc., you could have just bought a large chest freezer and put controls on that. Everyone's situation is different, however.

That being said, I think a much easier solution is to build the big insulated box and pump the cool air into it from the freezer. I've seen this idea from other posters on the forum so you might want to contact them for details, suggestions.

To brew ales and lager together (like in one big box), you keep the box and lager ferm temp and use ferm-belts to keep the ales warmer. I recently made my own ferm-belts from reptile heating mat material (the same stuff used to make the overpriced versions sold at home brew supply shops)...I made 2 belts for what I could have bought one ferm-belt from the home brew shop. Plug them into controllers and you are off to the races.

Good luck!