Lennox WHES040T45TN240S****

The 3,531 kWh figure does not appear in the registry itself. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used. It also used the DOE test's daily hot-water draw for the medium pattern. For this model the UEF is 0.92, from DOE's CCD registry, retrieved 2026-09-19. Among the 426 models registered as an electric tank at the medium draw pattern, it ranks 213th lowest for energy use. That places it in the second-lowest quarter of its class. Its gap to the class median of 3,531 kWh is 0 kWh, so under test conditions it uses the same energy as the class midpoint. The steps behind the annual figure are set out in how the annual cost is calculated.

This unit holds a rated volume of 37 gallons. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 51 gallons. The medium draw pattern represents a typical mid-sized household with a busy morning peak. A home whose morning demand stays within 51 gallons matches the conditions behind the 3,531 kWh figure. A home that uses much more or much less hot water does not match them. Its annual energy use would differ, and that value is not available in this data. For a like-for-like swap, you can find a same-class replacement by model number. To compare other fuels or sizes, use the selector by fuel, space and size.

Running cost is not stated here, because it depends on your own utility's electricity tariff. The 3,531 kWh a year at the medium draw pattern is one input; your rate per kilowatt-hour is the other. The cost calculator on your own ZIP applies your local tariff to that figure. This model sits 0 kWh from the class median of 3,531 kWh. At any given rate, its running cost therefore equals a median model's under test conditions. At other draws, this comparison is not available. The installed price range appears in its own block, with its source and date. It is a modeled installed-cost range, not a quote, and this text does not restate it.