How To Cool Down A Swimming Pool

Pool Care Chapters

There are a few cheap ways to cool down a swimming pool, and a couple of them do a surprisingly good job. Having said that, the best methods will cost you money, so be prepared to open your wallet at your local pool store if you want significant results. Regardless of what you choose or how much you spend, we’re sure that one of these options will help you cool down your swimming pool.

Okay, let’s go over some of the options. We’ll start with the most expensive choices and work our way down to free.

The Expensive Options

Pool Chillers

Pool Chillers reduce the temperature of the water by drawing out the heat and releasing it into the air. Depending upon the unit, pool chillers can cost $100’s to $1,000’s with an ongoing active-use cost of roughly $1 per day. The price will change with the quality of the product, the size of the pool that it was built to cool, and how quickly it can cool down a swimming pool. Of course, the size of your pool is the major factor that determines what pool chiller you will need. Generally speaking, to cool down your swimming pool, you will want a pool chiller that can lower the pool temperature by roughly 10 to 15 degrees over the course of about 10 to 14 hours.

Install a Reverse-Cycle Heat Pump

Regular pool heaters cannot cool your pool, but heat pumps can. Pool heaters warm the water by running electricity into a heating element. Pool pumps pull the warmth from the air to heat your pool. When we use it in reverse, it draws warmth from the water. If you happen to live in a mercurial climate, where the seasons shift from hot to freezing, one of these heat pumps might be exactly what you need.

Less Expensive Option

Pool Waterfalls

Waterfalls can be aesthetically pleasing and incredibly soothing. They can also be a great way to cool down a swimming pool. Exposing moving water to the cooler air can reduce the temperature by roughly 5 to 10 degrees. That’s wonderful for the hot days, but keep those cooling effects in mind if you’re ever trying to heat up your pool. 

Since pool waterfalls can cost as little as $100, they are a much less expensive alternative to pool chillers. Cheap prices often mean cheap products, so it wouldn’t likely be wise to purchase the cheapest waterfall on Amazon.

Inexpensive Option

If you don’t want to spend a lot, pool fountains and other aerators are sweet spots where function meets savings. The price range of pool fountains is between $10 (Bargain Bin of the Unwanted) and $100 (Fancy Products). $30 to $50 is enough to get you a quality product, so it isn’t necessary to go any higher than that.

Pool Misting Kit

Do not underestimate the power of a good misting system. These are a must-have for areas such as Arizona and Florida that have high temperatures throughout most of the year. Some misting systems claim to reduce temperatures by up to about 70°F. Of course, if those results are ever seen, they only apply to the immediate area of effect. The areas of effect of these systems can be pretty large and they are typically very inexpensive.

If you control the temperatures around the water, you can reduce the temperatures of the water. We can’t give exact numbers, but in most cases, it will be enough to justify this purchase.

Partial Drain and Refill

We don’t recommend this option because it is a bit wasteful. You will also throw off your pool chemistry every time that you do this. However, this isn’t our choice to make, so you should decide for yourself whether or not you want to use this method.

It is likely the city water will be colder than the water in your pool. Empty some of the water from your pool, and pump some of the city water into it. Your house pipes might be a bit warm, so you might need to let some of the warmed water into a drain for a little while. Once you get to the cool city water, start to refill the pool.

Practically Free Options 

Pool Filter at Night

Running your pool’s filter at night is a great solution for a couple of problems. Not only will it not cost you a penny more, but the cost of electricity goes down at night. More relevantly, running the filter at night will reduce the water temperature by increasing exposure to the night’s colder air and increasing evaporation.

Filter your pool at night if maintaining cool and comfortable temperatures is a constant struggle. Results will vary, but it will have a measurable and worthwhile effect.

Remove or Add Landscaping – Shade vs Wind

Direct sunlight can certainly heat up a pool. However, what casts a shadow also blocks the wind. Whether landscaping will help or harm will largely depend upon your location. Generally speaking, most pool experts recommend removing landscaping to improve the wind.

We understand this option on a near instinctual level. When we raise spoonfuls of hot soup to our mouths, we blow air upon them. That moving air pulls away heat from the soup and almost immediately makes it cool enough for consumption. Now picture that on a large pool-size scale, and that is what wind does for you. If you remove trees, foliage, and other wind-inhabiting obstructions, it will often help to reduce the heat.

Use Solar Heaters At Night (Solar Cooling)

Do you own solar heaters? If you do, then you might already have the answer to your cooling problem. When you run water through the solar heater during the day, the direct sunlight heats up the water in the tubes. During the night, without the sunlight, those same tubes will cool down the water. That makes this a situational solution since it will only help to cool the pool for the next day. 

Questions and Answers

Can I Cool My Pool With Ice?

You could, but it isn’t a realistic option. The effect is not worth the exorbitant price. If you’re looking for a cheap alternative, we’re guessing paying hundreds to thousands every time isn’t what you want. If you want to work it out yourself, you can use the following formula to determine how much ice you will need.

Pounds of ice needed=[(Gallons of Water / 1,000) x Desired Temperature Change] x 43.75

Let’s pretend to have a 10,000-gallon pool with a desired temperature increase of 10 degrees. That will give us the following result.

4,375 lbs. of ice = [(10,000 / 1,000) x 10°F] x 43.75

One pound of ice costs $.10 to $.30. That means the required 4,375 lbs. of ice will cost between $437.50 to $1,312.5. That’s a lot for a 10-degree difference.

Can Dry Ice Cool a Pool? (Dangerous)

By itself, unshielded dry ice is an ineffective coolant for swimming pools. It is also dangerous to swimmers and it will immediately throw off your pool’s chemical balance. When dry ice makes physical contact with water, it immediately transitions from solid ice to gas. It skips right over the liquid state, so there isn’t much time for it to actually cool the pool.

The resulting carbon dioxide that hovers over the pool’s water can poison and even kill the swimmers. There are a lot of these stories popping up in the news. It’s a tragically common occurrence for pool parties to turn into tragedies when dry ice is thrown into the mix by the uninformed.

The Pool Care Handbook & Video Course

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