How Do Chillers Work?

An Auto Water Cooled Chiller is a machine that removes heat from a liquid via a vapor-compression or absorption refrigeration cycle. This liquid can then be circulated through a heat exchanger to cool air or equipment as required. As a necessary byproduct, refrigeration creates waste heat that must be exhausted to ambient or, for greater efficiency, recovered for heating purposes. Concerns in the design and selection of chillers include performance, efficiency, maintenance, and product life cycle environmental impact.

Water Cooled Chiller Machine systems have these important elements:

Compressor: Provides the energy system.

Condenser: Rejects heat gained by the gas using ambient air or cooling tower water to condense the gas back to a liquid for use again by the evaporator. The condenser is a heat exchanger, which dissipates the heat absorbed in the evaporator.

System Expansion: The liquid refrigerant enters the expansion device which reduces pressure. By reducing its pressure abruptly decreases its temperature.

Evaporator: Cools the water, water/glycol or air by transferring the heat to the refrigerant which is turned into a gas. Compressor - takes this gas and increases its pressure so that ambient air or water can remove the heat. The coolant at low temperature and pressure through the evaporator, which like the condenser is a heat exchanger and absorbs heat.

Water Tank: holds the circulating coolant, usually water (can be water/glycol), tank is sized large enough to prevent turbulent flow in tank causing pump cavitation.

Pump: Circulates coolant from the holding tank to the evaporator and from the evaporator to the machine or process being cooled and back to the tank.

Control Panel: Houses temperature controller, compressor contactor, pump starter, 3-phase fuses, control transformer, safety controls, run and fail lights.

Pressure Gauge: High pressure switch and gauge.