Ruud PROG40S-38N RH62

This site calculated the 191 therms figure; the registry does not publish it. The calculation 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 medium pattern. This model's UEF is 0.58, taken from the DOE Compliance Certification Database, retrieved 2026-09-19. Ranked from lowest energy use under that test condition, it is 231st of 288. That puts it in the highest quarter of its class for energy use. A household that draws more or less hot water than the test assumes will use a different amount of gas. The registry does not show how large that difference would be. The steps are set out in how the annual cost is calculated.

The tank has a rated volume of 39 gallons. It also has a first hour rating, the gallons of hot water available in the first hour from a full tank, of 65 gallons. The registry lists it at the medium draw pattern, which DOE uses to represent a typical household's daily use. A home whose busiest hour needs more than 65 gallons needs more than this rating covers. For a home whose use matches the medium pattern, its energy use sits above the class median, as the opening figures show. To compare it with other gas tanks, use the water heater selector by fuel, space and size. You can also look up a same-class replacement by model number.

This text does not state the running cost because it depends on your own gas rate. The page multiplies the 191 therms a year by your state's average residential natural gas price, which it finds from your ZIP. So readers in different states will see different costs for the same PROG40S-38N RH62. The 6 therms gap to the class median also costs a different amount in each state. To see the figure for your own rate, use the cost calculator on your own ZIP. The installed price range appears in its own block, with its source and date. It is a modeled range, not a quote. Neither figure reflects how much hot water a particular household actually uses.