We Asked Reddit: What Size Water Chiller For Cold Plunge?

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When it comes to cold plunges, people have questions, and a lot of them. We’ve heard them all: When’s the best time to do it? How cold should the water be? How do you keep your cold plunge clean? What size water chiller for cold plunge is best? Etc., etc.

Well, for the sake of this article, we’re going to attempt to answer that last question. To help us out, we polled some fellow Redditors to get their opinion. Although we didn’t get one unanimous answer, there’s one size water chiller that clearly got the most votes.

We’ll tell you what size that is, why it might be your best option, and other things to consider when you’re shopping for a water chiller for cold plunge.

Key Takeaways:

• Selecting the right chiller size is crucial for maintaining optimal water temperature in your cold plunge.
• Consider factors such as tank volume, material and insulation, and desired water temperature when choosing a chiller size.
• Size your chiller based on the worst-case scenario during the hottest months of summer.
• Pay attention to the chiller’s coldest temperature and BTU rating to ensure it meets your cold plunge requirements.
• Ensure compatibility between the chiller, pump, and filter systems used in your cold plunge setup.

Factors Influencing Chiller Size for Cold Plunge

Now before we divulge what size water chiller most people choose, let’s first consider the factors that come into play when determining the appropriate chiller size for your cold plunge in the first place.

Volume of Water

The volume of your tank is a significant consideration. Let’s break this down as simply as possible.

Let’s assume your cold plunge holds 80 gallons of water, that’s about average. Now, let’s say you want to cool the water from a warm 80°F (27°C) down to a chilly 50°F (10°C), a difference of 30°F (17°C).

To accomplish that, 80 gallons of water needs to cycle through the chiller enough times to remove the excess heat. Since water doesn’t stay cool very well on its own (given a warmer ambient temperature), the cooling capacity of the chiller becomes paramount. In other words, if you have a huge tank of water matched to an underpowered chiller, it will be quite difficult to achieve any degree of icy temperatures to get the most benefit.

Bottom line: The more powerful the chiller, the faster and more efficiently it can take away that heat.

Insulation

The need for insulating your cold plunge cannot be overstated enough. As we just mentioned, water does not tend to stay cold on its own, particularly during the heat of summer.

A well-insulated tub will not only keep your water colder longer, but it will actually save you a ton of money in two ways. First, if your water chiller isn’t turning on as often, it’s not zapping electricity and running up your meter. Second, if your cold plunge is able to maintain temperatures, a more powerful (and expensive) chiller may not be necessary. For example, our 1/3HP chiller works remarkably well with the super-insulated Ice Barrel 300.

The woes of poor insulation are particularly true for those who own one of those portable ice bath pods. They’re easy and convenient, but notoriously struggle to stay cold.

Desired Water Temperature

The reality is, not everyone aspires to be like Wim Hof, plunging in Arctic-like waters. But if you do, the sizing of your chiller plays a role.

Given the right conditions, most water chillers can effectively lower the temperature down below 40 degrees Fahrenheit. The keyword being “right”. However, If you prefer not to press your luck, a larger chiller may be necessary to achieve and maintain that level of coolness.

Worst Case Scenario

This is the fourth and perhaps most important factor to consider when contemplating what size water chiller you need for your ice bath. Ask yourself, “What is the worst-case scenario?”

What does that mean, exactly? It means evaluating all of the conditions that will stress your cold plunge the most.

To assess your chiller size needs, ask yourself these questions:

• Is your cold plunge outside?
• Is it exposed to direct sunlight?
• What’s the hottest temperature during the summer?
• Again, how well insulated is your cold plunge?

Essentially, you want to think about all the external factors that will push your chiller to its limits and buy one based on those extremes.

Sizing a Chiller for Your Cold Plunge

Cold Plunge chillers come in a lot of different sizes from 1/4 HP all the way up to 1.5 HP. So what size water chiller are most people using for their cold plunge? According to our Reddit poll, most people opt for the 1/2 HP water chiller.

I have a 1/2 hp, Active Aqua that chills a 110 gallon stock tank in central North Carolina. Never had an issue keeping the water at temperatures from 36-50°F.

Reddit Commentator

Why do most people use the 1/2 HP water chiller?

A 1/2 HP (half-horsepower) water chiller is often considered the best option for most people due to several key reasons:

1. Efficiency: A 1/2 HP chiller strikes a good balance between cooling power and energy efficiency. It’s capable of cooling water relatively quickly without consuming excessive amounts of electricity.
2. Versatility: This size of chiller is versatile and suitable for a wide range of applications. It can effectively cool water in most cold plunges, bathroom tubs, stock tanks, and even commercial plunges. Its flexibility makes it a practical choice for many users.
3. Affordability: Compared to larger and more powerful chillers, a 1/2 HP chiller is typically more affordable upfront. It offers a good balance between performance and price, making it accessible to a broader range of customers.
4. Widely Available: Half-horsepower chillers are commonly available from various manufacturers. Higher-end units are oftentimes out-of-stock or back ordered.

Recommended Chiller Sizing Based on Tank Volume and Pump

If you’re still uncertain as to what size water chiller will best suit your needs, let’s explore a few more factors that will help you decide.

Although some more expensive chillers have built-in water pumps, many of the chillers on the market require a separate external pump.

You need to ensure that the chiller’s flow rate matches the requirements of your pump. The flow rate of the chiller should be sufficient to support the circulation of water through the pump and filter, keeping the water in your cold plunge constantly refreshed. Consult the specifications of your pump to determine the flow rate it requires and choose a chiller that can accommodate it.

The following table will not only help you determine what size water chiller you need but the water pump size too. The information below should serve as a baseline of the bare minimum requirements.

Water Chiller Size	Total Cold Plunge Water Volume	Recommended Pump Flow Rate (GPH)
1/4 HP	40-92 gallons	396-925 GPH
1/3 HP	60-100 gallons	400-1100 GPH
1/2 HP	90-172 gallons	800-1600 GPH
1 HP	80-250 gallons	1320-3900 GPH

To be clear, as far as the water chiller is concerned, you can never have a chiller that’s too powerful. The benefits of a more powerful chiller included faster chilling and colder temperatures.

The Best Recommended Water Chillers For Your Cold Plunge

Kind of the nice things about water chillers is that there’s a large variety of options to choose from. The most basic models are affordable and functional. Open your wallet a bit more and other chillers include high-end features like integrated Wi-Fi phone apps, UV and Ozone sanitation, and other neat features.

For our top 5 recommendations, check out the article: The 5 Best Water Chillers For Cold Plunge

Conclusion

For the majority of consumers, the #1 concern when buying a water chiller is cost. On the low end, they’ll run you about $500 and can go all the way up to $3000+. And we get it, you likely don’t want to spend more money than you need to, right?

Hey, saving money is never a bad thing, unless it’s at the expense of sub-par performance. Our advice is to take the information we provide here and match it to your individual needs and requirements.

More questions? Leave a comment below!