DOWFROST is an industrially inhibited propylene glycol-based heat transfer fluid. Aqueous solutions of DOWFROST fluid are designed to provide freeze/burst and corrosion protection, as well as efficient heat transfer, in water-based, closed-loop heating and air-conditioning systems. Recommended by Fadal for use in their spindle chill systems.
HVAC Systems Fluid Specification:
- The fluid must be industrially inhibited propylene glycol (phosphate based). 
- Must be easily analyzed for glycol concentration and inhibitor level. 
- Must be easily reinhibited using readily available inhibitors. 
- The fluid must pass ASTM D1384 (less than 0.5 mils penetration per year for all system metals. Fluid Installation
        1. Clean new of lightly corroded existing systems with a 1% to 2% solution of trisodium phospate in water prior to the installation of indusrially inhibited Propylene glycol fluid.
        2. Use only good quality water in solution. Water must have low levels (less than 25 ppm) of chloride and sulfate, and less than 50 ppm of hard water ions. Distilled or deionized water is recommended.
        3. Avoid use of automatic water make-up systems to prevent undetected dilution of the propylene glycol and possible contamination of the water system.