How to Convert Your Hot Tub Into a Refreshing Cool Plunge Pool

Hot tubs are great when it’s chilly out, but when the outdoor temperatures and humidity begin to rise, stewing in bubbling hot water may not seem very appealing. Fortunately, there’s something you can do about that. In an article for Hunker, Michelle Miley explains how to cool and then maintain your chilled hot tub — or should we say your new cool plunge pool. Here’s what to know.

How to cool a hot tub

Converting your hot tub into a refreshing plunge pool involves the following, according to Miley:

1. Turn down the heat, either setting your thermostat to 30 degrees or below, or turning the heat off completely.
2. Find a way to ventilate the hot tub. If it’s not in direct sunlight, just open the top. If it is, place a pool noodle or tennis ball under each corner of the cover to allow heat to escape.
3. Either wait for the water to come down in temperature on its own, or, if you need to speed up the process, drain some of the water and replace it with cold water from a garden hose.
4. If you add cool water from the hose, adjust the chemicals in the hot tub accordingly.
5. Run the jets in the tub to introduce cool air to the water and get the temperature down quicker. This will work faster when the sun is down.

How to keep a hot tub cool in the summer

Once the hot tub has reached your preferred temperature, you’re going to want to keep it that way. Miley suggests filling a few empty milk jugs or other plastic containers with water and freezing them, then popping them into the hot tub as needed, like giant ice cubes.

Another option, she says, is to purchase a hot tub chiller, which most manufacturers now offer as an option. But unless you’re trying to achieve a temperature that’s cold enough to be therapeutic (like athletes would use), you can probably keep your tub sufficiently cool without a chiller, Miley adds.

The good news is that the hot tub’s insulation works both ways — keeping the water nice and cool in the summer the way it retains the heat in the winter. This is especially effective if you put the cover on when you’re not using your new plunge pool.