Ruud PROG50-34U RH EC1

The 269 therms figure is computed by this site, not taken from the registry. It combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw for the high draw pattern. For this model the UEF is 0.63, from DOE CCD data retrieved 2026-09-19. Among the 414 gas tank models at the high draw pattern, it is 320th in order of lowest energy use. That places it in the highest quarter of its class for energy use. The figure holds only at the test's daily draw. A household drawing more or less hot water will use a different amount, and that amount is not available here. The steps are set out in how the annual cost is calculated.

The high draw pattern describes a larger household, or one where showers and laundry overlap. This model lists a first hour rating, the gallons of hot water available in the first hour from a full tank, of 80 gallons. Its rated volume is 48 gallons. A household whose busiest hour stays within 80 gallons matches the conditions behind the 269 therms figure. A household whose busiest hour needs more sits outside the rating, and the data here does not say how the unit would perform then. To check a like-for-like swap, same-class replacements by model number lists other gas tank models at the high draw pattern. The water heater selector by fuel, space and size compares across other classes.

The running cost is not written in this text, because it depends on your state's average residential gas price. The page computes it from your ZIP instead, using the same 269 therms at the high draw pattern. The gap to the class median carries into that cost: this model uses 9 therms a year more than the 260 therms median, at the test's daily draw. What that gap costs depends on the same rate, and it is unknown until a ZIP is entered. To run the figure on your own rate, use the cost calculator for your ZIP. The installed price range in its own block is a modeled range, not a quote.