What is a water heater’s recovery rate?

Recovery rate is the amount of hot water the water heater is capable of providing in a given period of time, not to be confused with first hour rating, which includes recovery rate plus 70 percent of the tank capacity

Answer

A water heater’s recovery rate is the amount of hot water the water heater is capable of providing in a given period of time. This is not to be confused with first hour rating, which includes recovery rate plus 70 percent of the tank capacity.

The amount of hot water provided will depend on several things. The wattage of a heating element in an electric water heater, temperature rise and the time frame for which you are measuring the recovery rate. The charts below are based on gallons per hour (GPH).

For example, in an electric water heater, if the wattage of the elements is 4500, the incoming water temperature is 40 degrees and you are heating the water to 120 degrees (temperature rise of 80 degrees) the recovery rate is 23.0 GPH.

Electric Water Heater Recovery Table(Calculated at 100% Recovery Efficiency) GPH RECOVERY AT INDICATED TEMPERATURE RISE
HEATING ELEMENT WATTAGE60 DEGREE70 DEGREE80 DEGREE90 DEGREE100 DEGREE
7505.14.43.83.43.1
10006.95.85.14.54.1
12508.57.36.45.75.1
150010.28.87.76.86.1
200013.711.710.29.18.2
250017.114.612.811.410.2
300020.517.515.413.612.3
350023.920.517.915.914.3
380026.022.319.517.315.6
400027.323.420.518.216.4
450030.726.323.020.522.5
500034.129.226.622.720.5
550037.632.228.225.022.5
600041.035.030.727.324.6