Glycol / Water Mixtures

Glycol / Water mixtures usually have a 60/40 or 70/30 glycol-to-water ratio. Ethylene and propylene glycol are "antifreezes." Ethylene glycol is extremely toxic and should not be used in domestic solar systems.

Food-grade glycol/water mixtures are usually used in a single-walled heat exchanger, as long as the mixture has been certified as nontoxic. Your supplier / contractor will have made sure that no toxic dyes or inhibitors have been added to it.

Most glycols deteriorate at very high temperatures. The pH must be checked to ensure if the mixture needs any adjustments or replacements to maintain its stability and effectiveness.