Recovery rate
How fast a water heater reheats — gallons of hot water it can make per hour.
Recovery rate is the number of gallons a water heater can raise to temperature in an hour while it's running. It's the engine behind a tank's [first-hour rating](/guides/what-size-water-heater-do-i-need-calculator): a high recovery rate means the tank refills with hot water quickly, so back-to-back showers don't run cold. Gas heaters generally recover roughly twice as fast as electric ones of the same size, which is why a smaller gas tank often keeps up with a household that would need a much larger electric tank. If your hot water [runs out too fast](/guides/hot-water-runs-out-too-fast), a weak recovery rate — or a failing burner or element — is a common cause.