Rheem SPEX75

The 615 kWh figure is calculated by this site, not stated by the registry. It combines the model's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw. This model's UEF is 0.96, and the draw used is the one set for the very small draw pattern. The underlying registry record comes from the DOE CCD, retrieved 2026-09-19. Because the test fixes the daily draw, the figure describes the test conditions, not a particular household. A home whose hot-water use differs from that draw would see a different annual figure, and this data does not say by how much. The steps are set out on the page explaining how the annual cost is calculated.

Against the 271 models registered as an electric tankless unit at the very small draw pattern, this model ranks 77th lowest for energy use. That places it in the second-lowest quarter of its class for energy use. Its annual figure is still equal to the class median, a difference of 0 kWh. The very small draw pattern covers small units: a single bathroom, or a point-of-use heater under a sink. Its maximum flow rate in gallons per minute is 0.8 at the registry rating. Whether that flow covers a given fixture depends on the fixture's own flow, which this data does not include. Other units in this class can be looked up to find a same-class replacement by model number.

The draw pattern also marks who this figure does not describe. A household expecting one unit to serve several bathrooms is outside the very small draw pattern, so 615 kWh would not apply to it. Running cost is not stated here, because it depends on your own utility electricity tariff applied to the 615 kWh figure. The page computes it from your ZIP rather than estimating a single amount. You can enter your ZIP in the cost calculator for your own electricity rate. The installed price range appears in its own block, with its source and date, as a modeled installed cost rather than a quote.