Which Chiller Is Best for Your DIY Cold Plunge?

Which Chiller Is Best for Your DIY Cold Plunge?

Winter is (mostly) gone… and with temps starting to climb, folks are diving into their cold plunge builds—literally. And one of the top questions I’ve been getting lately is about chillers. Which one should I buy? 

Let’s break it all down so you can pick the right chiller without overpaying—or overcomplicating—your build.

 

 

The TLDR Version

My Top Recommendation: stick with Active Aqua. 1/4HP is what 90% of people need to consider, 1/2HP if you are in an extreme climate. These have the LARGEST track record in the space and are proven to hold up to the elements, time and whatever else you throw at them.

2nd Choice (budget option): Rocita 1/3HP from Walmart. DO NOT BE FOOLED into paying more than $250-ish dollars for this chiller (see rant below). Not as reliable as the Active Aqua, but the best option for those on a budget.

RANT: There are countless “cold plunge” companies that sell these chillers for 2x and 3x the price with their logo printed in white on the front - they have horrible customer support when things go wrong, they are already making you pay more and who knows how long they will be in business in today's world. Tariffs are hitting HARD for businesses like this.

 

 

How much power do you need?

Here’s the truth: a more powerful chiller doesn’t mean colder temps. A 1/4HP chiller can hit 34°F just like a 1HP unit can. The difference is how fast it gets there. Once you hit your target temp, the chiller simply has to maintain it—so if you are doing an insulated DIY Cold Plunge build, a larger chiller can really be a waste of money.

So unless you’re living in a scorching climate, keep your cold plunge in direct sunlight or need your plunge ice-cold in 30 minutes flat after filling, save your money. 

 

 

My Top Chiller Picks

I’ve built and tested dozens of cold plunge setups, and there are only two chiller brands that I recommend.

🔹 Active Aqua

  • Durable and reliable – I’ve used mine outside, fully exposed to the MN elements. Rain, sun & snow and this thing is still kickin’ after 2.5 years.

  • Performs well even in extreme temps – cools down to 34 degrees

  • Sleek design & easy-to-understand controls

  • Runs quietly and has a solid track record – It’s what companies like Plunge, Renu and ModTub used.

🔹 Rocita (Walmart)

  • Budget-friendly and surprisingly capable

  • Great option for those just starting out on a limited budget

  • Easy returns and service through Walmart – this is important because these units do have more issues than the Active Aqua

  • DO NOT be fooled into buying a chiller that looks like this (with a cold plunge companies logo on it) for more than $280. See my rant at the top of this blog post 👍


 

 

Choosing the Right Size (Don’t Overthink It)

Here’s the quick and dirty version:

  • 1/4 HP – Best for most DIY plunges. Can cool down to 34°F. Affordable, efficient, and reliable. My 1/4HP can handle Minnesota summers without issue (high 80° to low 90°F weather)

  • 1/2 HP+ – Consider if you live in an extreme climate, your tub is not insulated and it will be exposed to sunlight.

 

 

Installation Made Simple

One thing that trips people up is plumbing the chiller into their system. Most of these chillers aren’t designed for off-the-shelf PVC or spa hose... but I’ve got you covered.

I carry custom chiller fittings that thread directly onto your unit and adapt directly to PVC or flexible spa hose. They save you the headache of Frankenstein-ing a solution together (which I’ve done and you certainly can still do, too!).

➡️ Check out the DIY Cold Plunge PVC Chiller Fittings

Need help installing? I’ve got a tutorial on that too. 

 

 

Final Thoughts

There’s no need to waste money on an oversized chiller, or be the early adopter on a chiller that doesn’t have a proven track record. Stick with tried-and-true brands like Active Aqua or even Rocita, and you’ll be in great shape.

Pair your chiller with step-by-step plans and custom fittings, and you’ll be plunging in no time—without the stress.

Got questions? Shoot me an email. I love helping you guys build cold plunges that actually work.

Stay cold,
Joe

 

 

P.S.

Here’s a list of the chiller’s I personally own and have tested:

  • Active Aqua 1/4HP

    • First chiller I ever got (3rd year of operation now)

    • Has lived outside in rain, snow & sun

    • Still works great, some minor blemishes on the shell from being outside.

  • Penguin 1/2HP HE

    • Worked great for 1.5 years and then died

    • Does not hold up to the elements

    • Very fast cooling

  • EcoPlus 1/4HP

    • Used this for my bathtub conversion plan

    • Same abuse as the Active Aqua above

    • LED Display Panel does not fully light up all the numbers anymore

  • Active Aqua 1/2HP

  • Active Aqua 1/10HP

    • Tested as an indoor-only setup

    • Was hoping it would be enough in a climate controlled environment… it was not

  • Rocita 1/3HP

    • I have two of my good friends using this chiller (indoors)

    • Still going strong after a year of use

    • Seem to be more “lemons” in the bunch based on feedback in my Facebook Group

  • Vevor 1/4HP

    • Works fine

    • I’m skeptical of the long-term durability

    • Fittings are a pain to configure

  • Plunge STANDARD Chiller

    • Did initial testing prior to Plunge releasing it

    • Very powerful, comes with all the fittings needed

    • Fairly loud, no ozone and the way it operates will make it hard to add sanitation

    • High price, but works great for what it does

  • Generic All-In-One

    • I burned through two of these units from the same company… 

    • Long story short, not reliable. Do not recommend.

 

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