What Is Chilled Water?

Chilled water serves as one of the main components in a hydronic cooling system. These systems utilize water to transfer heat energy from inside of a building to the outdoors, which helps to cool the interior of the structure. Chilled water serves as an alternative to traditional refrigerant, which is used in most air conditioning and cooling systems.

On a typical project, chilled water is produced on site using a large chiller or cooling tank. These devices contain some form of heat exchange system, which captures heat energy in the water and exhausts it to the outdoor. By removing the heat energy, these cooling systems chill the water, allowing it to be used to cool the building. The same water moves through piping within the cooling system in a continuous loop, absorbing heat energy from indoors and expelling it to the outdoors.

Chilled water from the chiller or cooling tank enters the building's air-handling unit through a network of pipes or cools. A fan or blower within this unit blows air over the pipes. The chilled water within the pipes absorbs the heat energy, leaving the air cool. This cool air then travels through the building's duct system to distribute cool air to each room. Fresh chilled water continuously passes through the pipes to absorb more heat energy and keep the air cool.

In some parts of the world, municipal agencies supply chilled water to homes and businesses, much in the same way they provide water or sewer service. This eliminates the need for chillers and cooling tanks, and allows building owners to cool the structure easily and effectively. This water may be cooled using a central cooling tower, or may be derived from naturally cold sources, like lakes and rivers. This type of central chiller supply is often known as a district cooling system, and is a paid service for homeowners and building managers.

Chilled water cooling systems provide many benefits to users. They generally require less maintenance than traditional refrigeration systems, as there is no need to check, balance, and refill the refrigerant on a regular basis. Chilled water also costs much less than refrigerant products, which can reduce the cost of repairs over time. These systems also pose very little risk of leaks, and can be repaired with relative ease. Finally, by eliminating the refrigerant, chilled water systems protect the environment from potential pollution and global warming effects commonly associated with many refrigerants.