Water Heater Calculator

This water heater calculator provides an approximate heating time for various heater configurations. Select the amount of water in the tank, the temperature change required, and the size of heaters installed, and the calculator will provide a heating time in minutes.

This calculator assumes 100% efficiency, which is typical for immersion water heaters, but if you know your system has an efficiency less than 100%, provide a proportionally less number for 'watt output'.