Glycol Freeze Protection Mix

Glycol percent and concentrate gallons from manufacturer freeze-point curves.

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Details, formula, and sources

Linear interpolation across manufacturer freeze-point curves for propylene glycol and ethylene glycol; gallons of concentrate = system_volume × concentration_target.

Manufacturer freeze-point curves (Dow Dowfrost / Dowtherm SR-1) by name.

Free at dow.com / chemours.com technical bulletins.

Estimate. AHJ and licensed plumber / gas fitter govern. Verify against the IPC / IFGC edition adopted in your jurisdiction.

Field names used by the API: system_volume_gal, target_burst_F, glycol_type, glycol_percent, concentrate_gal

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