RELIANCE WATER HEATERS GPDL-40 3**

This site calculated the 163 therms figure; the registry does not list it. The calculation uses the model's UEF, the ratio of hot water delivered to energy used, which is 0.68. It also uses the daily hot-water draw from the DOE test for the medium pattern. The UEF comes from the DOE CCD, retrieved 2026-09-19. So the result holds only at the federal test's daily draw. If your household uses more or less hot water than the test assumes, your yearly total will be different. The page on how the annual figure is calculated sets out each input and step. The 22 therms gap to the class median is measured the same way, so both numbers depend on the same test condition.

The medium draw pattern represents a typical household of a few people with a busy morning. This model's first hour rating, the gallons of hot water available in the first hour from a full tank, is 74 gallons. Its rated volume is 38 gallons. The 5th ranking describes homes whose morning demand fits within that first-hour figure. The comparison covers only the 288 models registered as a gas tank at the medium draw pattern. Units that use another fuel or are tested at another draw pattern are not part of that ranking. To check a comparable unit in the same class, use find a same-class replacement by model number.

Some homes need more than 74 gallons of hot water in the first hour. Those homes fall outside the conditions behind these figures. For them, the 163 therms total and the class rank do not describe their likely use. The figure is also measured in natural gas, so it does not apply to a home on another fuel. This text does not give a yearly running cost. That cost depends on your state's average residential gas price applied to the 163 therms total. The cost calculator on your own ZIP works it out at your rate. The installed-cost range in its own block is a modeled range, not a quote.