ZEREX ZXELRU1 DEX-COOL Antifreeze / Coolant – Gallon; ZXELRU1

An antifreeze is an additive which lowers the freezing point of a water-based liquid. An antifreeze mixture is used to achieve freezing-point depression for cold environments. Common antifreezes also increase the boiling point of the liquid, allowing higher coolant temperature. However, all common antifreeze additives also have lower heat capacities than water, and do reduce water's ability to act as a coolant when added to it.

Because water has good properties as a coolant, water plus antifreeze is used in internal combustion engines and other heat transfer applications, such as HVAC chillers and solar water heaters. The purpose of antifreeze is to prevent a rigid enclosure from bursting due to expansion when water freezes. Commercially, both the additive (pure concentrate) and the mixture (diluted solution) are called antifreeze, depending on the context. Careful selection of an antifreeze can enable a wide temperature range in which the mixture remains in the liquid phase, which is critical to efficient heat transfer and the proper functioning of heat exchangers. Most if not all commercial antifreeze formulations intended for use in heat transfer applications include anti-corrosion and anti-cavitation agents (that protect the hydraulic circuit from progressive wear).

A coolant is a substance, typically liquid, that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system. Some applications also require the coolant to be an electrical insulator.

While the term "coolant" is commonly used in automotive and HVAC applications, in industrial processing heat-transfer fluid is one technical term more often used in high temperature as well as low-temperature manufacturing applications. The term also covers cutting fluids. Industrial cutting fluid has broadly been classified as water-soluble coolant and neat cutting fluid. Water-soluble coolant is oil in water emulsion. It has varying oil content from nil oil (synthetic coolant).

This coolant can either keep its phase and stay liquid or gaseous, or can undergo a phase transition, with the latent heat adding to the cooling efficiency. The latter, when used to achieve below-ambient temperature, is more commonly known as refrigerant.

The gallon is a unit of volume in British imperial units and United States customary units.

The imperial gallon (imp gal) is defined as 4.54609 litres, and is or was used in the United Kingdom and its former colonies, including Ireland, Canada, Australia, New Zealand, India, South Africa, Malaysia and some Caribbean countries, while the US gallon (US gal) is defined as 231 cubic inches (3.785411784 L), and is used in the United States and some Latin American and Caribbean countries.

There are four gills in a pint, two pints in a quart, and four quarts (quarter gallons) in a gallon, with the imperial gill being divided into five imperial fluid ounces and the US gill being divided into four US fluid ounces: this, and a slight difference in the sizes of the imperial fluid ounce and the US fluid ounce, give different sizes for the imperial gallon and US gallon.

The IEEE standard symbol for both the imperial and US gallons is gal, not to be confused with the gal (symbol: Gal), a CGS unit of acceleration.