A Quick Guide to Glycol

Glycol coolant is one of the most common cooling liquids used in chillers everywhere. It comes in two forms: propylene and ethylene. 

Types of Glycol

Propylene: Propylene glycol is a synthetic liquid substance that absorbs water. Propylene glycol is also used to make polyester compounds, and as a base for deicing solutions. Propylene glycol is used by the chemical, food, and pharmaceutical industries as an antifreeze when leakage might lead to contact with food. 

• Toxic: No
• Freezes: -74.2°F

Ethylene: Ethylene glycol, a derivative of ethylene oxide, is used for the manufacture of polyester fiber for clothes, upholstery, carpet, and pillows and the blending of automotive engine antifreeze and coolant. Ethylene glycol is also used to manufacture fiberglass for products such as jet skis, bathtubs, and bowling balls. A major use is in the production of polyethylene terephthalate (PET) resin, a recyclable plastic, such as soda and water bottles. 

• Toxic: Yes
• Freezes: 8.78°F

Heat Transfer Fluid

Glycol of both types are used in chillers as an antifreeze due to their low freezing points. Its use as a heat transfer fluid is unparalleled, but different industries use one or the other depending on the level of toxicity that they can handle. Food industries use propylene ethanol, as doing so won’t harm consumers, while ethylene glycol is preferred in industries where contamination is not a factor.

Ethylene glycol’s freezing point is much higher than propylene glycol. When ethylene is mixed with water, however, the freezing point drops considerably.

Find Your Chiller

North Slope Chillers offers the best in chiller technology, regardless of which type of heat transfer fluid you use. For more information about how North Slope Chillers can meet your cooling needs, call (866) 826-2993 or email [email protected].