Ohio Water Heater Authority is an independent, privately owned water heater service company and a Transit & Flow™ company. We are not a government agency and are not affiliated with the State of Ohio or any public utility.
First-hour rating is the number of gallons of hot water a tank water heater can deliver in one hour of use starting with a full tank. It combines stored capacity with how fast the burner or elements reheat, and it is printed on the EnergyGuide label.
FHR is the right number to size a tank against, not the gallon capacity alone. A 50-gallon gas tank with a strong burner can out-deliver a 50-gallon electric tank because it recovers faster. We match the FHR to your household’s busiest hour, not an average day.
See how we use it in the water heater sizing guide or run the size calculator.
Answer a few plain-English questions and see estimated installed options in about three minutes.
Pick one and we take you straight there.
Rather talk? Call 844-792-8374, answered 24/7.
