Chiller blanket proof of concept.

[J A]

I've been thinking about various strategies for cooling carboys and other 5 gallon batch fermenters. I'll have glycol chilling capacity but that only works on my bigger fermenter that are equipped with chiller coils. For carboys and buckets or small conical I need some way to pump glycol to chill outside the container. There are some bladder type chiller blankets at various price points but I keep thinking that DIY solution would be pretty easy.
I thought about tubing wrapped around the fermenter and covered with some insulation and I'm sure that would work. The notion of more contact surface led me back to the bladder/blanket option. I realized that I have the technology to do that in the form of my vacuum bag food storage sealer. By using parchment paper as a blocker I can us the sealer to make baffles and tubing inlets.
I have to refine the design and process but initial test shows that I can produce a bladder that I can pump fluid through.

 

[Minbari]

The trick with that would be termination. how will you connect tubing to it?

I would think silicon tubing or even bicycle tire tube wrapped around it might work. a barb and pipe clamp would be easy to seal either one.

Maybe daisy chain a bunch of hot water bladders together (the rubber ones used for sore muscles)

 

[J A]

I'll post a pic of the layout I'm using. It's possible to make a "spout" at each end that can have a tube inserted and clamped. I've definitely thought about the tubing but the surface area is pretty skimpy. A coil on the inside in contact with the liquid is great but tubing that's trying to cool the carboy has a harder time of conducting heat and cold. The bag will have a comparatively huge contact are and be much more efficient. If it holds up, I wouldn't be surprised if I could crash a carboy down to lagering temps. I'm making a full-size version that I'll wrap around a carboy and do some stress testing and see if the seals will hold up and not develop leaks.

 

[Minbari]

I'll post a pic of the layout I'm using. It's possible to make a "spout" at each end that can have a tube inserted and clamped. I've definitely thought about the tubing but the surface area is pretty skimpy. A coil on the inside in contact with the liquid is great but tubing that's trying to cool the carboy has a harder time of conducting heat and cold. The bag will have a comparatively huge contact are and be much more efficient. If it holds up, I wouldn't be surprised if I could crash a carboy down to lagering temps. I'm making a full-size version that I'll wrap around a carboy and do some stress testing and see if the seals will hold up and not develop leaks.

That would be my concern. you don't have alot of pressure moving the glycol, but even 3-4psi can push liquid out.

@ $45 a gallon, i wouldn't want to lose it, lol

 

[J A]

Leak testing in progress. So far nary a drop gone astray. I'm running sanitizer through it. Not sure it'll hold up to cold liquid but I have a lot of vacuum bags in the freezer for many months at a time.

 

[Donoroto]

You can always find heavier plastic film.