Inexpensive/Cheap Glycol Fermenter Setup Idea

[camcdonald1]

I recently completed my fermentation chamber & plastic conical with mason jar yeast harvester. Winter will be ending soon in MN and I’ll need to address high summer temps in my garage. I’m looking for the cheapest way to cool my conical and if possible the entire fermentation chamber/closet (for wine/cider in carboys). I want to leave manual monitoring/ice feeding out of the equation and go with some kind of automated glycol setup. I’d also like to avoid taking apart an a/c unit if possible and instead utilize a spare dorm room fridge that I already have. I’m not overly concerned with efficiency or speed of chilling (cold crashing).

My initial thought which I’m hoping you can help confirm/dispel is a 6 gallon bucket in the dorm fridge, pond pump submerged with a closed loop vinyl tubing or silicone hose that runs from chilled glycol in the refrigerator, drill through fridge walls, drill through fermenter walls and in/out top of 15 gallon carboy. All controlled by an STC-1000. I think it would be great if I could have 25 feet of hose to play with and just drop that into the fermenter and loop back to the fridge (i.e. no coiled stainless chiller). I know vinyl/silicone isn’t going to have the heat transfer efficiency of SS, but, again I’m not concerned with efficiency or speed. As long as the fermenter can drop xx degrees from ambient, I don’t care how long it takes to get there (within reason).

My questions would be:
---Would a suspended flexible hose/tubing work inside the fermenter, or is it a requirement to have the chilling mechanism inside the conical be metallic/stainless?
---Can I save myself from having to clean additional chilling elements (the hose/tubing or SS coil if I go that route) and wrap the chilling mechanism around the outside of the plastic conical?
---Would the chilled conical be enough to cool its surroundings inside the fermentation chamber (possibly with a fan on it)? The chamber is well insulated and held temps steady during cold winter months with a forced air fan. My ideal situation would be something like this: garage gets up to around 90 max, chilled conical drops 20 degrees to ferment ales, surrounding fermentation chamber hovers above conical, somewhere around 75 degrees to keep wine/cider happy.

 

[day_trippr]

- wrt to a hex inside the conical, the thermal transfer efficiency of SS ain't great but it's hella better than plastic.

- the efficiency of an external coolant loop is going to be sketchy as even if you somehow get the entire loop wrapped perfectly and insulate the hell out of it, the tubing is still only only making contact in a thin strip along its entire length. While it could still be done, I'd think the summer heat would challenge the efficiency.

- stealing cold from the conical to keep the whole cabinet hospitable might be asking more than the system will manage in the dead of summer. You'll just have to see.

btw, faced with your chosen options I'd consider dismantling the dorm fridge and immersing the cold plate directly in your glycol reservoir. MUCH more efficient than using air as a transfer medium...

Cheers!