A. O. SMITH GCBL-40 4**

The 194 therms figure is computed by this site. The registry does not publish it. 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 medium pattern. For the GCBL-40 4**, the UEF is 0.57, taken from the DOE CCD and retrieved 2026-09-19. The figure holds only at the federal test's daily draw. If your household draws more hot water each day than the medium pattern assumes, it will use more gas than 194 therms. If it draws less, it will use less. The registry data cannot tell you how much more or less, so that amount is not available here.

Among the 288 models registered as a gas tank at the medium draw pattern, the GCBL-40 4** has the 278th lowest energy use. That places it in the highest quarter of its class for energy use. Its 194 therms sits 9 therms above the class median of 185 therms a year. Its first hour rating, the gallons of hot water available in the first hour from a full tank, is 68 gallons. Its rated volume is 38 gallons. If you are matching an existing unit on first hour rating and tank size, compare those two figures. If lower gas use within the same class matters more to you, you can find a same-class replacement by model number and compare its rank with 278th.

This text does not state the running cost of the GCBL-40 4**. It depends on your state's average residential gas price. The page works it out from your ZIP in the cost calculator for your own ZIP, using the 194 therms figure at the medium draw pattern. The steps behind that result are in how the annual cost is calculated. No installed price range is published for this model. Its ratings lie outside the range that the cost database's model was fitted on, and the site does not stretch that range beyond it. For that reason, the installed price of the A. O. SMITH GCBL-40 4** is unknown here.