Cold plunge chiller size calculator
Water volume + target temperature → recommended chiller HP and estimated running cost. Runs 100% in your browser — nothing is sent anywhere.
How the math works
Cooling load (BTU) = gallons × 8.34 × ΔT (°F). Required BTU/hr = load ÷ pull-down hours × climate factor (×1.5 more if uninsulated). Chiller HP ≈ BTU/hr ÷ 12,000, rounded up to the next standard size (¼, ⅓, ½, ¾, 1 HP) with a safety margin. Holding-temp runtime assumes the chiller works ~25–40% of the day depending on climate; electricity = HP × 0.746 kW × runtime × rate.
The Cold Pod tubs we recommend are chiller-compatible with standard water in/out ports. Talk with your doctor before starting a cold-plunge routine.
This guide is for general information only and isn’t medical advice. Talk to your doctor before starting heat or cold therapy.