Chillers – How to Size a Chiller for Your DIY Cold Plunge

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Introduction

If you have been thinking about building a cold plunge for home use, or if you have already have been plunging but use ice, using a chiller is an option to consider.

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A chiller is like the brain of your DIY cold plunge, and sizing a chiller correctly is essential to a setup that keeps your water at your desired temperature, and does so efficiently.

The best practice is to size a chiller based on the worst-case use scenario. For most people this is during the hottest months of summer.

When in doubt, get the next bigger sized chiller!

I am an official reseller for Penguin Chillers and if you’re in North American and looking for a new chiller, I can help you with sizing.

Most chillers are advertised with HP, which is horsepower. However, HP will not tell you how fast a chiller can actually cool the water or the coldest temperature it can reach.

When shopping for a chiller, you should find out the coldest possible temperature and the BTUs. Keep in mind that the coldest temperature listed is in IDEAL conditions. The below variables all impact how a chiller will perform, regardless of its temperature range and BTUs.

For more information about BTUs, see this article:

For cold plunges, chillers below 1/4 HP are not recommended because they generally will not get your water cold enough and will have to run very frequently to work at all, which not only makes them more expensive, but shortens their life span.

Also keep in mind that the quality of chillers, including how they are designed and the materials used can make a significant difference.

How Chillers are Rated

In the consumer market, chillers are typically rated with HP (Horsepower). However HP does not tell you how much (or how well) a chiller will work.

The number to look at is the BTU rating of the chiller. BTU stands for British Thermal Units, which is defined as “the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.” If you have a gas grill for your outdoor summer cookouts, you’ll know it is rated in BTUs.

BTUs are also used to measure how much heat can be removed from water with a chiller. Two chillers with the same HP might have very different BTU rating.

Also Keep in mind that some chillers might perform slightly or significantly lower than their listed BTU rating.

Questions to Ask

Here are the questions I ask my clients to determine the best chiller for their cold plunge.

1. What size (volume) tank do you have?
   This is a good place to start. Most DIY cold plunges use tanks with less than 400 gallons. If that is the case. The general guidelines are below, but you definitely need to consider all of the other variables.
   
   50 – 150: 1/4 to 1/2 HP
   150 – 200: 1/2 HP to 1 HP
   200 – 400: 1 HP to 1.5 HP
   400 – 600: 1.5 to 2.5 HP
   600 – 1,000: 2.5 HP+
   
2. What material is the tank made of (plastic, metal, etc.)
   This variable is not critical, but does make a difference if your tank is not insulated. Metal transfers heat much faster than plastic. If your tank is uninsulated and gets direct sun exposure, the water will heat up faster in a metal tank than in a plastic tank.
   
3. Is your tank insulated? If yes, what kind of insulation did you use, how thick is it, and how was it applied?
   2 – 3 inches of insulation is recommended. The highest standard is a 2-part, closed-cell, high-density spray foam insulation with moisture/vapor barrier properties. If your tank is not insulated, going with the next higher sized chiller might help, especially if you have direct sun exposure.
   
4. What is your target water temperature?
   Not all chillers are capable of cooling to the same temperature. Some aquarium chillers have a low temperature rating of 50 – 55 F. Others are in the 40F range, and some can bring the water to 34 – 39F.
   
   The low temperature range needed depends on your goals and how the cold plunge will be used.
   
   Keep in mind that a chiller’s temperature range is given under “ideal conditions.” Anything less than ideal can result in warmer water temperatures.
   
5. Where will your cold plunge be located indoors (spare bedroom, studio, retail facility, etc.) or outdoors (garage, covered patio, backyard, etc.)?
   There can be a significant difference between having your chiller inside and outside.
   
6. Here are additional questions to ask about your cold plunge location:
   a. What is the highest temperature during the hottest month of the year?
   b. What is the lowest temperature during the coldest month of the year?
   c. What is the average humidity during the hot months?
   d. How many hours of direct sunlight will your cold plunge receive?
   
   A chiller outside in Arizona during July will perform very differently than a chiller inside a climate controlled room. A chiller outdoors in central Texas, or south Louisiana (locations with high humidity) will perform very differently than a chiller in northern California where the humidity is much lower.
   
   If you have high temperatures below 80F in a relatively dry climate, a 1/2 HP or 3/4 HP chiller is a good place to start.
   
7. Regarding the usage of your cold plunge:
   a. What time of day will it be used? (mornings, afternoons, evenings, etc.)
   b. How many people will be using it, and for how long?
   c. Will you use your chiller as part of a contrast therapy protocol with a sauna or hot tub?
   
   If you your cold plunge is outside and you only use it once per day in the morning, the relatively cooler evening temperature will help the chiller do its job. If you use your cold plunge several times throughout the day when temperatures are generally warmer, going with the next-sized chiller is a good idea.
   
   Each person using a cold plunge can increase the water temperature by 1 – 2 (or more!) degrees F. If you have many people plunging within a short time, having a more powerful chiller will help keep the water closer to your desired temperature.
   
   If you plan to do many rounds of contrast therapy, a more powerful chiller will be helpful. I’ve seen a the water temperature in a tub with low powered chiller increase by 10 degrees F after 40 minutes of several rounds of going directly between a traditional Finnish sauna and the cold plunge.
   
   I stopped by a local facility in Austin to see their contrast therapy setup with a cold plunge and sauna. Someone had just finished a 45 minute session. The temperature in the Mozoko Forge (which was set to 33°F) was at 45°F after several rounds of the person going back and forth between the sauna. The Morozko uses a chest freezer compressor, which is not anywhere near as powerful (or fast) as a chiller, but also keep in mind that chillers do take time to bring down the water temperature.
   
8. How far away from the tank will your chiller be located?
   The best practice for simple DIY cold plunges is to keep the chiller, pump and filter as close to the tank as possible. If you are building a permanent tank (ex. pouring concrete or using masonry), you might prefer to have your equipment farther away. If it is more than 10 feet away, you’ll need to take into consideration the size of pipe and how well it will be insulated.
   
9. Do you have a plan for your pump/filter yet? If yes, which ones are you using?
   All pumps will have a certain flow rate (gallons per minute/hour) and a certain amount of pressure that they create, which is measured in pounds per square inch (PSI).
   
   All chillers have minimum and maximum flow rates in order to work correctly. If the flow rate is too low or too high, the chiller will not work efficiently or at all. With Penguin Chillers, we know that Danner pumps from 500 gph up to 1,800 gph will work.
   
   Chillers also have a limit on the maximum pressure. Too much pressure (for example, using some pumps meant for swimming pools) can damage the chiller. The Danner pumps recommended above all work with Penguin Chillers.
   
   If you want to use a different pump than Danner with a Penguin Chiller, please contact us so that we can make sure the flow rate and pressure will work.

Penguin Chillers

Penguin Chillers are designed and built in the US. They range from 1/2 HP up to 2.5 HP for the consumer market. More powerful chillers are available for commercial clients. Hundreds of people in the US and Canada are using Penguin chillers for their DIY cold plunges.

If you decide to buy a Penguin Chiller from me, you’ll receive the same price, service, lead time, and warranty as you would buying directly from Penguin. You’ll also receive my help in answering questions about designing and setting up your system. Your patronage helps me support our global cold plunge community- and my family- and is appreciated.

You can find more information about Penguin chillers and links to pricing on my website here:

If you have specific questions, fill out the contact form (see the main navigation menu at the top).

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Choosing the Right Chiller for Your Cold Plunge: Understanding BTU

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If you are thinking about building a DIY cold plunge, it’s essential to buy a suitable chiller to cool your water. In this article, we’ll discuss the importance of BTU (British Thermal Unit) and how it relates to chiller capacity. So get ready to make an informed decision and plunge into icy waters! BTU is…

Benefits of Using a Water Chiller for your Ice Bath Journey

Consistent Temperature Control

Imagine stepping into your ice bath and experiencing the perfect degree of cold every single time. That's what a water chiller offers: reliable and Consistent Temperature Control. Unlike ice cubes that melt and change the water temperature, a chiller keeps your ice bath at the exact coldness you've set, anywhere typically between 45°F and 55°F (7°C - 13°C). This level of control is essential for those seeking therapeutic benefits from their ice baths, as it helps to ensure optimal muscle recovery and inflammation reduction without the risk of the water becoming too cold or too warm.

Faster Cooling Time

Waiting for water to drop to the right temperature can be a tedious part of the process. However, with a high-quality water chiller, you'll enjoy a Faster Cooling Time. Advanced models can lower water temperature to 37°F (3°C) swiftly, eliminating the wait and making it more convenient to fit a cold plunge into your schedule. This quick action is particularly beneficial if you're looking to reduce downtime in your wellness routine or if you need a rapid cool down after an intense workout session.

Energy Efficiency

In today's world, Energy Efficiency is more than just a buzzword; it's a necessity. Using a water chiller for your ice baths can be more energy-efficient than constantly buying and using ice. Chillers are designed to maintain low temperatures without the same level of energy drain that ice production and refrigeration can cause. Your cold plunge setup becomes not only more sustainable but also potentially cost-effective in the long run as you save on energy bills. Plus, many chillers come with energy-saving features that minimize their ecological footprint while still providing the chilling power you need.

If that's too complicated and you prefer to shop a ready made ice bath and chiller system shop our ice bath & cold plunges.

Types of Water Chillers for Ice Baths

When diving into the world of cold water therapy, you'll come across various types of water chillers, each designed to cater to your specific needs. Understanding the differences between the types of chillers available will ensure you equip yourself with a system that maximizes efficiency and aligns with your wellness goals.

Recirculating Water Chillers

Recirculating Water Chillers are the go-to for consistent and rapid cooling. They operate by continuously pumping water through a cooling unit, maintaining a stable water temperature throughout your ice bath session. This type of chiller is built for speed and can swiftly bring down water temperatures, which is particularly beneficial if you're looking to minimize preparation time.

Most recirculating chillers will have the flexibility of fine-tuning temperatures to your desired level. They often come with digital interfaces, allowing precise control over your bathing conditions. With models capable of reaching as low as 2ºC (35ºF), they cater to even the most extreme cold therapy enthusiasts.

For those with space constraints, the more compact models are ideal. They can be easily stored and moved, providing a convenient option for those who require portability. It's critical to assess the power of these models in accordance with your needs—some are built to cool up to L, a considerable volume for any ice bath routine.

Immersion Water Chillers

On the flip side, Immersion Water Chillers offer a direct cooling approach. By directly placing the cooling element into the water, these chillers cool the water surrounding it effectively. This method is particularly advantageous for home brewers seeking precise yeast pitching temperatures, as immersion chillers can significantly reduce water temperature.

Immersion chillers are simpler in design and often lightweight, which makes them a breeze to maneuver. They don't require complex setups and are perfect if you're after a straightforward cooling solution. Despite their seemingly modest approach, they are highly capable of achieving the low temperatures needed for effective ice baths, ensuring your muscles receive the optimal cold exposure needed for recovery.

Both recirculating and immersion water chillers boast features that cater to your specific temperature and capacity requirements. Evaluate your preferences in terms of ease of use, temperature range, and volume capacity to determine which chiller will offer the most substantial benefits for your ice bath therapy. With the right chiller, maintaining and controlling your cold plunge has never been simpler.

Factors to Consider When Choosing a Water Chiller for Ice Bath

As you continue to explore the intricate world of ice bath therapy, you'll find that choosing the right water chiller is paramount to achieving the perfect balance between efficiency and comfort. In this section, you’ll get a clear picture of the key elements to consider before making your purchase.

Cooling Capacity

The cooling capacity of a water chiller is one of the most critical factors to weigh in. You want a chiller powerful enough to swiftly reduce the water temperature and maintain it within the optimal range for cold therapy. In essence, larger motors generally equate to a higher cooling capacity, but this also might reflect on your utility bill. Your goal should be to find a chiller that meets your requirements without overkill.

Quick cooling is ideal, but balanced with precision. An oversized chiller may cool the water too rapidly, potentially causing discomfort, while an underpowered one could fail to provide the desired therapeutic coldness. Therefore, scrutinize the cooling specifications relative to the volume of water in your ice bath setup.

Nancent supply professional and honest service.

Temperature Range

A critical feature in a water chiller is the ability to provide a wide temperature range. Typically, for cold plunge therapy, the water temperature should hover between 45°F and 55°F (7°C - 13°C). Ensure that the chiller can comfortably operate within this range. Some models are software-limited for safety, preventing extremes that could lead to ice build-up or insufficient cooling.

Advanced chillers often come with customizable settings, such as temperature presets and adjustable thermostats to dial in your preferred cooling level. The broader the temperature spectrum your chiller covers, the more versatile its use will be.

Size and Portability

Your available space and how often you intend to move the chiller should guide your decision on size and portability. When space is at a premium, compact designs that don’t compromise on power are essential. Portable chillers are invaluable for those who prefer flexibility, such as moving the chiller between different locations or storing it when not in use.

Remember that portability doesn't always mean lightweight, so look out for features like wheels or carrying handles that enhance maneuverability.

Noise Level

The therapeutic benefits of a cold plunge can be diminished by a noisy chiller. You’re looking for a model that whispers rather than shouts, keeping the noise level to a minimum. The quieter the operation, the more you can relax and focus on the cold therapy experience without any intrusive sounds that could disrupt your tranquility.

Maintenance Requirements

Finally, consider the maintenance that your water chiller will demand. Regular upkeep is crucial for optimal performance and longevity. Models with self-cleaning features save you time and effort, allowing you to focus more on enjoying the benefits of your ice bath.

Take note of the filtration and sterilization systems; they are paramount for ensuring a clean and healthy plunge environment. Some chillers boast UV disinfection which is particularly effective at keeping water at its cleanest. Also, take into account how readily available replacement parts and customer support are because maintenance is not just about the cleaning but also about ensuring continuous operation with minimal downtime.

IDEAL TEMPERATURE RANGE FOR COLD WATER IMMERSION THERAPY

Cold water immersion therapy, also known as an ice bath, can be a helpful tool for athletes and fitness enthusiasts to aid in muscle recovery, sleep, mood, and the immune system. There is some debate as to the ideal temperature range for an ice water bath but a good place to start is between 50-59 degrees Fahrenheit (10-15 degrees Celsius).

Read more on cold plunge temperature and timing.

The TLDR is that different temperature ranges offer various mental and physical benefits for the body. A temperature range of 60-68 degrees Fahrenheit (15-20 degrees Celsius) can help improve blood circulation and reduce muscle soreness. For more advanced cold therapy, a temperature range of 45-50 degrees Fahrenheit (7-10 degrees Celsius) can help reduce inflammation and promote brain health.

It is important to gradually adjust to colder temperatures to avoid shock to the body. Start with a higher temperature and gradually decrease the temperature over time. It is recommended to stay in the ice bath for 5-15 minutes for maximum impact.

NECESSARY EQUIPMENT TO GET STARTED WITH AN DIY ICE BATH CHILLER SYSTEM

POWER CORD SETUP AND REQUIREMENTS

Setting up a water chiller for ice baths is easy and straightforward. The power cord is located at the back of the unit for easy access. To set up the system, simply plug the unit into a standard 110V electrical outlet and connect the chiller to the cold plunge tub with the supplied hoses and clamps. The power cord setup and requirements are straightforward, ensuring that you can enjoy your ice bath without any hassle. With the chiller properly connected, you can maintain the perfect temperature for your ice bath while keeping the water clean and fresh.

 GALLONS OF WATER REQUIRED FOR AN ICE BATH EXPERIENCE

To get the full power of an ice bath, it's essential to have the right amount of water, which can vary depending on the size of the chiller unit and the tub used. Typically, 50 to 100 gallons of water are needed for a full ice bath. However, some factors such as outdoor temperature, frequency of water changes, and personal preference can affect the amount of water required.

It's crucial to choose a water chiller for cold bath that can efficiently handle the required amount of water. Depending on your preferences and budget, you can either opt for a high-capacity professional-grade chiller or a more affordable and portable DIY chiller system. Regardless of your choice, managing the amount of water in your ice bath using a water chiller is crucial for an effective recovery experience.

FILTRATION SYSTEM: KEEPING YOUR WATER CLEAN AND PURE

A filtration system is an essential feature of a water chiller for cold plunge, which ensures clean and pure water for an optimal ice bath experience. The filtration system comprises several crucial components that work together to remove impurities and particulates from the water, resulting in crystal clear and bacteria-free water.

The filter stand is at the heart of the filtration system, which houses the filter canister and the 5-micron filter. These components act as the first line of defense against impurities and pathogens, such as algae, minerals, and other sediments that may be present in the water. The 5-micron filter is designed to capture even the smallest particles of dirt or debris, ensuring that the water is as clean and pure as possible.

Tips for Maintaining a Water Chiller

Maintaining your water chiller is not just about prolonging its lifespan. It's also about ensuring you get the most efficient performance for your ice baths. Remember, optimal functioning goes hand in hand with diligent upkeep, so keep reading for some essential maintenance tips.

Regular Cleaning

Your chiller’s performance hinges on cleanliness. Regular Cleaning prevents mold and bacteria buildup that can compromise the system and your health. Every couple of weeks, roll up your sleeves and:

• Scrub the water reservoir thoroughly to keep it free of contaminants.

• Clean the external and internal components, reaching into those nooks and crannies where dirt can hide.

• Rinse the water filter with a brush and tap water—it should happen every 12 weeks.

• Ensure that replacement of the water filter occurs monthly to avoid restricted water flow and subsequent damage.

A clean chiller isn't just about aesthetics—it's about performance and safety.

Checking and Replacing Parts

To prevent mid-plunge mishaps, you'll want to check hoses and connections for leaks or wear:

• Tighten loose connections as soon as they're spotted.

• Replace any worn parts without delay, especially those exposed to constant wear.

Don’t forget about descaling if you’re using tap water. Mineral buildup is a stealthy saboteur of efficiency. Follow the manufacturer’s guidance on how and when to descale your unit. This proactive approach stops problems before they can start and ensures seamless operation.

Storage and Maintenance during Off-Season

When the season changes and you're no longer taking regular ice baths, don't just shove your chiller in a corner. Proper storage is key to its longevity:

• Store the chiller in a cool, dry place away from direct sunlight or extreme temperatures.

• Before packing it away, give it one last thorough clean and dry; lingering moisture is the enemy.

• Inspect the chiller before and after the off-season to catch any issues that might have arisen during storage.

Remember, a well-maintained chiller means less downtime and more time enjoying the cold plunge benefits. Keep it clean, keep it running, and keep it ready for when you need it.

Conclusion

Choosing the right water chiller for your ice bath is crucial for an invigorating and safe experience. You've learned about what to look for and how to maintain your unit for peak performance. By keeping these tips in mind you'll ensure your chiller meets your needs and lasts for years to come. Remember to clean regularly and stay vigilant with maintenance. With your new knowledge you're ready to make an informed decision and enjoy the benefits of a perfectly chilled ice bath.

If you want to learn more, please visit our website Water Chiller for Cold Tub.