Pump Up Your Portacool

Ever wonder what that extra switch is next to the power button on your Portacool portable evaporative cooler? Sure, it says “Pump,” but what does that pump actually do inside the cooler? The pump actually plays an important role in the evaporative cooling process that takes place within Portacool portable evaporative coolers. Without a pump or water, there is no cooling effect, basically giving you an industrial-sized fan.


How Evaporation Works

The evaporation process (what creates the cool air) takes place via the media in an evaporative cooler. The media is the brown, honeycomb-looking material that is often mistakenly referred to as an evaporative cooler pad, filter, cool cell, or cardboard. All Portacool products are equipped with Kuul Comfort™ evaporative media, the highest-quality evaporative media on the market made in the USA exclusively for Portacool products.

In a Portacool evaporative cooler, water should be continuously pumped across the evaporative media at as high a rate of flow as possible without entrainment. In layman’s terms, as much water as possible without creating any spitting effect. You can increase or decrease the water flow by turning the water adjustment valve. If the evaporative cooler is entraining – or spitting droplets out of the front fan side – turn the water down slowly until the droplet carryover is stopped. In dry climates, more water will be needed to keep the evaporative media wet, while humid climates will require less water most days. A higher rate of water flow also allows for the media to “self-clean” or “wash” away dirt or other build up on the face of the media.

So, What About the Pump

To operate your evaporative cooler at maximum efficiency – that is, at optimal cooling potential – the evaporative media needs to be completely wet. Visually that means it is a uniform dark brown in the back from the water with no visible streaks of dryness. This is where the pump does its part by distributing water evenly. Without the pump running, the evaporative cooler will not produce cool air; it will only blow around the warm air in the building just like a regular shop fan. As the fan pulls hot air through the saturated evaporative cooling media, the water evaporates and the air temperature is lowered.

The pump also works in conjunction with the Liquid-Level Indicator (LLI) – a safety feature that automatically shuts off the pump when there isn’t enough water in the reservoir – ensuring the pump does not fail. In fact, for Portacool portable evaporative coolers, a red light will come on to let you know when this mechanism has turned on and your pump has shut off. That is your cue to add water. If you are running your product connects to a garden hose this should not be an issue, but if you are running on the reservoir alone it could happen.


Running the pump not only allows for cool air production, but it also eliminates water from becoming stagnant in the reservoir. This can deter the creation of bacteria and build up in the water that flows through your cooler.

Part of the cooler’s maintenance regimen should include switching off the pump 15
minutes before you turn the fan off. This will allow the fan to pull air through the media and help the evaporative media to completely dry. This will ensure you have healthy media that is in tip-top shape for longevity. Next time you turn your cooler on, just be sure to flip the pump switch back on when you turn the power on to ensure you feel cool air coming out.

Find out more maintenance tips and information about your Portacool evaporative cooler.