Yup.Feldon said:Cold water ex fridge by pump would be adequate to cool a small homebrew fermentor. Glycol is overkill IMO.
And the subtitle version reads: water cooled from a fridge is good for small volumes. Radiator coolant is pretty good too...Lyrebird_Cycles said:Yup.
Brine reduces the volumetric heat capacity of the coolant but allows you to run at a lower temperature. This results in a decrease in fridge plant efficiency but an increase the efficiency of the jackets, so it's mainly useful in large tanks*.
If you have enough jacket surface area / fermenter volume you be will be fine with water at say 2 oC**
If you do want to run brine, you don't need glycol. Freezing point depression is a colligative property so it depends on the molarity of the solution, not the solute. Calcium chloride and metho both work well, a corrosion inhibitor may be useful depending on system design.
*Surface area to volume ratio decreases as the 2/3 power of volume assuming tanks shape is constant.
** Unless you need to be able to chill your fermenters / storage tanks below zero, then you obviously need a coolant that is below your target temperature. This is the case in wineries where chilling to - 2 to - 4 oC is standard practice for stabilisation.
Never in commercial FV vessels. Try 2 to 2.5bar max operating and 3 bar manufacturers test. The real issue is the inner skin, we have seen UK manufactured vessels pillow in at 3.5 to 4 bar. We actually install a pressure bypass valve on the chiller outlet to restrict the pressure to 2 to 2.5 bar in the glycol ring main. Also, we dont use automotive glycol (ethylene glycol) due to its toxicity. Propylene glycol is the preferred additive.Lyrebird_Cycles said:FV cooling jackets are normally dimple plate to prevent that very problem. Dimple jackets are rated to about 6 Bar.
The prices I've seen are:Hippy said:
Interested to see how much these will be as well as the glycol unit.