LOCHINVAR GPDNL-40 1**

The 242 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 0.7. The figure holds only at the federal test's draw. Your household's actual hot-water use is not available here. A home drawing a different daily amount would use a different amount of gas than 242 therms. The UEF comes from the DOE Compliance Certification Database (CCD), retrieved 2026-09-19. The steps from UEF to annual use are set out in how the annual cost is calculated.

The high draw pattern stands for 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 75 gallons. Its rated volume is 38 gallons. Its class is the 414 models registered as a gas tank at the high draw pattern. Within that class it ranks 90th lowest in energy use, which places it in the lowest quarter. The ranking does not cover models tested at other draw patterns or on other fuels. The 242 therms figure is stated for natural gas only, so it does not describe a home without gas service. To check a model from the same class, use find a same-class replacement by model number.

The running cost is not stated in this text. It depends on your state's average residential gas price, so the page computes it from your ZIP. The same 242 therms a year can produce a different cost from one state to the next. Likewise, the 18 therms gap below the 260 therms class median becomes a cost gap only at your own rate. To see both at your 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 installed-cost range, not a quote, and this text does not restate its figures.