What mechanism does a chiller use to remove heat from a liquid?

A chiller uses either a vapor-compression or absorption mechanism to remove heat from a liquid. In vapor-compression chillers, a refrigerant is cycled through a series of processes that include evaporation, compression, condensation, and expansion. During the evaporation phase, the refrigerant absorbs heat from the liquid being cooled, causing the refrigerant to vaporize. This vapor is then compressed, raising its temperature and pressure, and subsequently, in the condenser, it releases the absorbed heat to the environment as it condenses back into a liquid. This cycle effectively removes heat from the liquid being cooled.

Absorption chillers operate on a different principle, using a heat source (such as natural gas or waste heat) to drive the cooling process instead of mechanical energy. They also involve the absorption of the refrigerant into a solution, which aids in transferring heat from the liquid.

Both systems are effective in providing cooling for applications in commercial and industrial settings, making them the primary mechanisms used in chillers for heat removal. The other choices, such as convection currents, electric resistance, and chemical reactions, do not accurately describe the primary methods employed in astute chiller operation for heat extraction.