Design Matters: Efficient Heat (Cold) Exchange
Cold plunging can be as simple as filling a bathtub with ice or as complicated as sawing a hole in an icy lake. But for those who want to make cold immersion a regular practice, and those who live in warm climates year-round, the benefits of a purpose-built cold water spa are obvious.
Cold plunge tubs, however, vary significantly in design. Aesthetics aside, one of the biggest differences is in how the water is chilled, and how effective that system is in cooling your body. The goal, after all, is to quickly reduce your body temperature.
Tubs that use still water, i.e. water that doesn’t circulate, generally require larger, more energy-intensive cooling systems, as well as colder starting water temperatures or longer immersion times—this is because the layer of water directly next to the skin warms as you sit, reducing the cooling effect of the water on your body. With stationary water systems you either need to sit in colder water, or sit longer, to achieve the perfect chill.
Cold plunge tubs that use circulating water, like the Eureka cold water immersion tub, cool more quickly and efficiently because the flowing water removes the layer of warm water next to your skin and replaces it with freshly cooled water from the chiller. Removing this thermal barrier has the same effect as wind chill: making it feel colder because your radiating body heat is instantly removed by the moving water, in the same way that wind can make a cold day feel utterly bitter. By pairing a high flow pump with an energy-efficient chiller sized perfectly for our tub, we’ve created an effective chilling system that cools your body quickly, reducing the need for extremely low starting temperatures and long immersion times.