ARISTON GSN50T2-3-*

The figure of 269 therms was not measured in a home. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, which is 0.63 for this model. It also uses the DOE test's daily hot-water draw for the high draw pattern. The source is DOE CCD, retrieved 2026-09-19. The high draw pattern describes a larger household, or one where showers and laundry overlap. A home with different daily use will land at a different figure. This page does not estimate a figure for that case.

Among the 414 gas tank models registered at the high draw pattern, this unit has the 320th lowest energy use. That places it in the highest quarter of its class for energy use. It sits 9 therms above the class median of 260 therms. Both figures are at the same draw pattern, so the comparison is like for like. The first hour rating, the gallons of hot water available in the first hour from a full tank, is 82 gallons. The rated volume is 47 gallons. These two figures describe capacity and are not inputs to the energy figure on this page. To filter other units by fuel, space and size, use the water heater selector.

Running cost is not stated in the text, because it depends on your state's average residential gas price. The figure of 269 therms is for natural gas at the high draw pattern. Multiply it by your price per therm to get a yearly cost. The cost calculator on your own ZIP does this for you. The method for the annual cost is described on its own page. This model suits a household that matches the high draw pattern. A household with lighter use falls outside the condition of the 269 therms figure. To compare against another unit, find a same-class replacement by model number and check its figure at the same draw pattern.