LOCHINVAR HETF-50 1**

The 3,531 kWh figure is computed by this site; the registry does not publish it. It combines the registry's UEF, the ratio of hot water delivered to energy used, with the daily hot-water draw the DOE test sets for the medium draw pattern. This model's UEF is 0.92. The registry values come from the DOE Compliance Certification Database, retrieved 2026-09-19. The figure holds only at the test's daily draw, so a household drawing more or less hot water will use a different amount. The rank of 213th of 426 counts only electric tanks at the medium draw pattern. It does not compare this unit with other heater types or draw patterns. The method behind the annual energy and cost figures sets out each step.

The medium draw pattern stands for a typical mid-sized household's hot-water use. This model's first hour rating, the gallons of hot water available in the first hour from a full tank, is 74 gallons. Its rated volume is 45 gallons. A home whose busiest hour stays within 74 gallons falls inside the use this unit was rated for. A home whose morning peak regularly exceeds 74 gallons falls outside that condition. The registry does not show how the unit performs there, so that performance is unknown. If you need a unit in the same class with different ratings, you can find a same-class replacement by model number.

Running cost is not given in this text, because it depends on your own utility's electricity tariff. The page computes it from your ZIP instead, using the same 3,531 kWh at the medium draw pattern. This unit sits 0 kWh from the class median of 3,531 kWh. At any given rate, its computed cost therefore equals the cost of the class median energy use. Its place at 213th of 426 does not change with the tariff, since every electric tank in the class runs on the same fuel. To see the figure for your area, use the running cost calculator for your own ZIP. The installed price range shown in its own block is a modeled range, not a quote.