So I'm getting into more process cooling for medical equipment. Many have been speccing max 30% prop level. On the comfort chillers in my region, we always maintained 25% for burst protection down to 0 degrees. These process chillers run 24/7 year round, so don't I need to worry about freeze protection. To have them protected down to 0 degrees, I need a 36% mix.
I talked to a couple of the manufactures, and they told me 30% is enough. That gets me down to 10 degrees. Is that enough? I usually not one to argue with manufactures.