Glycol Chillers

Glycol-loop chillers circulate a glycol and water mixture — Penguin recommends a 35–40% glycol mix — to reach 28°F, below what a water chiller can do. Rated for cryotherapy panels, specialty cooling and other sub-freezing applications. All units from Penguin Chillers, manufactured in Knoxville, Tennessee, from 1/3 HP through 5.0 Ton commercial.

These are not the chillers for a cold plunge. If you are outfitting one, you want a water chiller. Penguin's support team gave us three reasons, and they are worth knowing before you spend:

• Copper coils, not titanium. The glycol units use copper cooling coils, which are less resistant to corrosion from plunge chemistry such as chlorine. The water chillers use titanium.
• No water circulation ports. A glycol unit has no convenient inlet and outlet for running water through it.
• A different architecture entirely. A glycol chiller holds its own reservoir at temperature; submerged pumps then move the cold glycol out to jacketed tanks or heat exchangers.

What about cooling a plunge indirectly, through a heat exchanger? Penguin confirms it is possible — and that it is meaningfully less efficient than cooling water by direct contact with the cooling coil. You would be paying for capacity the design gives away. If you are planning an outdoor install in a cold climate, or a commercial build that needs to hold below a water chiller's floor, speak with your Wellness Concierge before you buy either type. We will put the question to Penguin's team directly.