What type of equipment operates by cooling through the evaporation of water into the air system?

The correct choice is the evaporative cooler, which operates based on the principle of evaporative cooling. In this system, water is drawn into a pad or filter where it absorbs heat from the air passing through it. As the water evaporates, it changes from liquid to vapor, which requires energy in the form of heat, thereby cooling the air. This cooled air is then circulated into the space that needs to be cooled.

Evaporative coolers are particularly effective in dry climates where the humidity is low, as the evaporation process is more efficient in these conditions. The simplicity and energy efficiency of evaporative coolers make them a popular choice for cooling in certain environments.

Other options, such as air conditioners and heat pumps, utilize refrigerants and mechanical processes to cool air, while refrigerated coolers use a refrigeration cycle involving compression and condensation. These systems do not rely on the evaporation of water in the same manner as evaporative coolers do.