Heat Transfer Fluids

DOWTHERM™  A heat transfer fluid is a eutectic mixture of two very stable compounds, biphenyl (C12H10) and diphenyl oxide (C12H10O). These compounds have practically the same vapor pressures, so the mixture can be handled as if it were a single compound. DOWTHERM A fluid may be used in systems employing either liquid phase or vapor phase heating.DOWTHERM™  RP heat transfer fluid is a diaryl alkyl intended for use in applications that require liquid phase heat transfer. DOWTHERM RP fluid can be used in non-pressurized systems and is pumpable to 0 °C.DOWTHERM™  SR-1 heat transfer fluid is a formulation of 95.5 weight percent ethylene...

Corrosive ​All salts are very corrosive Long term protection is impossible even with corrosion inhibitors Glycols (without corrosion inhibitors) are corrosive to most metals Oxidize to form acids --> low pH --> acidic pH is corrosive Must use correct type of corrosion inhibitor technology Corrosion damage can occur in less than 2 years Worse for high temperatures and high exposure to air or dissolved O2 Dow heat transfer fluids are properly formulated with corrosion inhibitors and pH buffers which: Passivate metal surfaces to prevent corrosion Neutralize degradation compounds to prevent pH drop Thermoxidatively stable to provide long term protection

For customers using more than 2000 Liters of inhibited glycol, Dow offers free annual fluid analysis consisting of the tests below. Dow will also recommend how to improve the system if needed. ​Glycol concentration ​Reserve Alkalinity and pH Corrosive water ions: chloride and sulfate Corrosion inhibitors & corresponding corrosion rates Total hardness: calcium and magnesium Non-Dow inhibitors: e.g. MBT, nitrate & nitrite