Rheem SPEX8208T

This site calculated the 603 kWh figure; the registry does not list it. The calculation uses the registry's UEF, the ratio of hot water delivered to energy used, and the DOE test's daily hot-water draw for the very small draw pattern. This model's UEF is 0.98. Both inputs come from the DOE Compliance Certification Database, retrieved 2026-09-19. It ranks 10th lowest for energy use among the 271 electric tankless units registered at this draw pattern. That puts it in the lowest quarter of its class. The figure applies only at the federal test's daily draw. A household that draws more or less hot water will use a different amount. Each step is explained on the page about how the annual cost is calculated.

The very small draw pattern covers small units that serve a single bathroom, or point-of-use heaters under a sink. The registry lists this model's maximum flow rate in gallons per minute as 0.7. The 603 kWh figure and the 10th rank both describe that use and no other. If you are replacing a unit at a sink or in one bathroom, you can compare the old unit's rating with the 0.7 listed here. You can also compare its energy use with the 615 kWh class median. To list other models registered in this class, search by model number in the same-class replacement finder.

This page gives no energy figure for this model at a larger draw pattern. Its energy use for a whole house or several bathrooms is not available here. For those jobs, the selector by fuel, space and size lists models tested at other draw patterns. The running cost is not written in this text. It depends on your own utility's electricity rate multiplied by 603 kWh a year. The page calculates it from your ZIP in a separate block. At any rate, the saving over a class-median model is the cost of 12 kWh a year. You can run the same check for other models in the cost calculator for your ZIP. The installed price range on this page is an estimate from a cost model, not a quote.