How to Cool Pool Water: The Ultimate Guide

Nothing quite beats the joy of diving into a cool, refreshing pool on a scorching summer day. However, if your pool water feels more like a warm bath than a cooling retreat, it’s time to learn how to cool pool water effectively. Understanding how to manage your pool’s temperature is essential for an enjoyable swimming experience, and in this blog post, we will provide you with several practical and innovative solutions to maintain the perfect pool temperature during the sweltering summer months.


Why Does Pool Water Heat Up?

Understanding the factors that contribute to rising pool water temperatures is the first step in learning how to cool pool water. Typically, the warming of pool water can be attributed to one of three key factors: the outside temperature, the use of a pool cover, and the operation of a pool heater.

Firstly, the ambient or outside temperature plays a significant role in determining your pool’s water temperature. On hot, sunny days, the sun’s rays directly heat the water, causing the temperature to rise. This effect is more pronounced if your pool is exposed to sunlight for most of the day and lacks any form of shading.

Secondly, a pool cover, although useful for maintaining cleanliness and reducing evaporation, can inadvertently heat your pool water. This occurs when the cover traps the sun’s heat, creating a greenhouse effect that warms the water beneath it. While pool covers can be great for retaining heat during cooler months, they can have the opposite effect during the heat of summer.

Lastly, a pool heater might be the culprit behind your warm pool water. Pool heaters are designed to warm water to a comfortable swimming temperature, particularly useful in cooler climates or during the off-season. However, leaving a pool heater on during the summer months can lead to excessively warm water.

The good news is that if the increased temperature is due to the pool cover or heater, the solutions are straightforward. Removing the pool cover will allow the trapped heat to escape and the water to cool down naturally. Similarly, switching off the pool heater will cease the active heating of the pool, permitting the water temperature to drop. Understanding these factors is pivotal in implementing effective strategies to cool your pool water.

Using a Pool Cover

One of the simplest ways to cool your pool water is by using a pool cover. Pool covers work by reflecting sunlight and heat away from the pool surface, thereby reducing the overall water temperature. Specialty solar pool covers can be particularly effective as they are designed to prevent heat from the sun from being absorbed into the water.

Pool Water Circulation

One effective strategy on how to cool pool water is enhancing water circulation. Running your pool’s pump and filter during the cooler nighttime hours can help circulate the water and lower its temperature. This is especially effective when combined with other cooling methods.

Install a Pool Shade

Installing a shade structure over your pool can be an effective way to cool pool water. By blocking direct sunlight, pool shades can significantly reduce the amount of heat absorbed by the pool water. Pool shades come in various forms, including shade sails, pergolas, and umbrellas, and can be chosen to match the aesthetics of your backyard.

Evaporative Coolers

Evaporative coolers, also known as pool coolers, work on the principle of evaporative cooling to lower your pool’s water temperature. These devices spray fine water particles into the air around your pool, which when evaporated, naturally cools down the pool water.

Using a Pool Chiller

A pool chiller works similar to an air conditioning unit, but for your pool. It takes in warm pool water, cools it down within the system, and then returns the cooled water back into the pool. While this method can be quite effective, it is also the most expensive option for cooling your pool water.

Adding Cool Water

If you are wondering how to cool pool water in the most straightforward way, it could be as simple as adding cool water to your pool. This can be done by using your garden hose to add cooler water during the hottest parts of the day. However, this method might not be efficient for larger pools or in regions with water restrictions.


Learning how to cool pool water effectively can drastically enhance your swimming experience during the hot summer months. Whether you choose to use a pool cover, enhance water circulation, install a pool shade, utilize an evaporative cooler, invest in a pool chiller, or simply add cool water, each of these methods can contribute to maintaining a refreshing pool temperature. Remember, the best approach often involves combining several of these methods to ensure an inviting and enjoyable pool experience all summer long.