Everything about evaporative coolers suggests utilitarian action, with nature’s most potent process taking its cue from the ambient temperature around our homes and workplaces. And we do mean potent, for every weather pattern, every cloud, and every single storm system on our globe relies on fluid state transitions. Remember that all-encompassing power as we wonder why evaporative coolers work best in warm climates.
Gives Thermal Properties a Helping Hand
That’s right, if the ambient temperature is already warm, then the evaporating moisture requires less energy to cross its transition threshold. The mild room or balmy outdoor patio is full of energized air particles, and this energy aids in the conversion of solid water so that it quickly disperses into that air. At this point, the laws of thermal dynamics take over. No energy can be lost or destroyed, only converted or traded, so the transition effect causes the air to cool. This essential principle drives evaporative appliances, but what happens when the heat really pushes the thermometer mercury high?
It’s the job of the compact fan unit to induce this vaporizing effect, which is the case in all but the coldest situations. The hottest rooms, though, hardly require this supplemental mechanism, for the air itself generates enough energy to trigger the water-soaked pads. Soaked continually by an internal series of tubes, as propelled by a power-economical pump, the moist pads stay saturated, but the airborne thermal energy coefficient accelerates the fluid phase transition cycle. In short, the warm air acts as an abridged conversion mechanism, a force that readily dissipates the water as a fine mist. Certainly, the fan still functions as an important member of the appliance, but it’s no longer responsible for the evaporation effect. Instead, evaporation becomes its secondary feature. Primarily, the fan now acts as a distribution system, so it pushes the cooling air into the far corners of the heated space.
If the room is cold, well, there’s no need for an evaporative cooler, but the unit can still function happily as a freshness promoter. Then, as the workplace environment heats up or the office crowds with warm bodies, an element of intelligence enters the process. The air temperature passes 21°C or thereabouts. Simple but irresistible laws of physics then have their way as the warm air engenders the evaporative cooling cycle. The thermostat setting will obviously impact this function slightly, as will the type of pad media, but the result will always be a fresh and cool breeze.