What Is a Chiller?

Versatile Applications of Chillers

Chillers come into play where standard air conditioning units fall short. You might have seen these systems perched on rooftops of hotels or shopping centers. They are also integral in industrial processes that generate significant heat, providing the necessary cooling. Beyond industry, chillers are crucial in medical technology and research, cooling equipment such as MRIs, CT scanners, and lasers.

How It Works

Understand how a chiller works can be complex, as it involves various chemical processes. In simple terms, a chiller removes heat from inside a building and expels it outside using cold water. A pump circulates the chilled water to the areas that need cooling. As it flows through these spaces, the water absorbs heat and then returns to the chiller. Inside the chiller, the heat is transferred to a refrigerant, which circulates in a separate loop and releases the heat into the environment. Some chillers can also function as heat pumps, meaning they can provide heating by moving heat from outside to inside.

Common refrigerants used in chillers include propane, ammonia, and F-gases. The type of refrigerant determines how low the water temperature can go. In some cases, the cooling liquid remains fluid even at zero degrees Celsius, allowing it to keep flowing smoothly. Special low-temperature chillers can cool fluid down as low as -45 degrees Celsius.

Types of Chillers

Chillers can be categorized based on how they dissipate heat:

• Air-Cooled Chillers: The units release heat through fans.
• Water-Cooled Chillers: These units transfer heat to water.
• Split Units: These consist of an indoor and an outdoor component connected by refrigerant lines.

Air-cooled chillers are best suited for outdoor installations, where large amounts of warm air can be discharged. If a chiller needs to be installed indoors, a water-cooled model is a better option. For split units, you need to have space for one component inside and one outside. Given the high cost of purchasing a chiller, renting one can be a cost-effective solution.