Richmond SCG40T03ST34U1

The 188 therms figure does not appear in the registry itself. This site calculates it from the registry's UEF, the ratio of hot water delivered to energy used. The second input is the DOE test's daily hot-water draw for the medium draw pattern. For the SCG40T03ST34U1, the UEF is 0.59, as listed in the DOE Compliance Certification Database (CCD) and retrieved 2026-09-19. The result holds only at the federal test's daily draw. A household that draws more hot water than the test assumes will use more gas than 188 therms a year. A household that draws less will use less. The page on how this site calculates annual energy and cost sets out each step.

The registry lists the SCG40T03ST34U1 at the medium draw pattern, which DOE uses to represent a typical household's daily hot-water use. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 67 gallons. That rating comes from a rated volume of 38 gallons. The rating does not cover a household whose busiest hour regularly needs more than 67 gallons. The registry holds no data on real household use, so this page cannot say how a specific home compares with the test. If a home needs a different fuel, space or size, the water heater selector by fuel, space and size filters on those factors.

The running cost does not appear in this text because it depends on your state's average residential natural gas price. The page calculates it from your ZIP by applying that price to 188 therms a year. For another address, the cost calculator for your own ZIP repeats the same step. The same price applies to the 3 therms gap to the class median noted above, so the cost of that gap also varies by state. The comparison class is the 288 models registered as a gas tank at the medium draw pattern. To check other models in that class, find a same-class replacement by model number. The installed price range has its own block with its source and date. It is a modeled range, not a quote.