A. O. SMITH UPVA-40Y 1**

The 635 kWh figure is not a measurement taken in a home. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, which is 0.93 for this model, and the DOE test's daily hot-water draw for the very small draw pattern. The fuel is electricity, and the source is DOE CCD, retrieved 2026-09-19. The class median is 615 kWh, so this unit sits 20 kWh above it. It ranks 218th lowest in energy use of 271 models, which places it in the highest quarter of its class for energy use. A different daily draw in your building would give a different yearly figure.

This model is listed under the very small draw pattern, which covers small units: a single bathroom, or a point-of-use heater under a sink. Its registry maximum flow rate in gallons per minute is 0.4. These values describe the small uses that draw pattern represents. They do not describe a whole house, and this page has no figure for this model at a larger draw pattern, so that value is not available. If your use is larger than the federal test's daily draw, the 635 kWh figure does not apply to you. The water heater selector filters by fuel, space and size, and the same-class replacement finder searches by model number. The comparison here is limited to the 271 models in this one class.

The running cost is not written in this text because it depends on your own utility electricity rate. Multiplying 635 kWh by that rate gives a yearly cost at the federal test's draw, and the cost calculator for your ZIP does this for you. The steps are set out in how the annual cost is calculated. Because this model is 20 kWh above the class median of 615 kWh, the same rate and the same draw would give it a higher yearly cost than a median model in this class. Your actual use depends on your household's draw, which this page cannot know. The modeled installed-cost range appears in its own block with its source and date, and it is not repeated here.