Ariston GSN30T1-3-*

It holds 29 gallons in the test, 1 gallon less than its 30-gallon sold size. It delivers 72 gallons of hot water in the test's first hour. Reheating lets it give 43 gallons beyond the 29 gallons in its tank. Among 763 gas storage models, 488 have a higher first-hour rating. The median gas storage model gives 78 gallons in the first hour of the test.

On Oct 26, 2026, this heater was not listed as ENERGY STAR certified. In the test, 40% of its energy does not reach the hot water (UEF 0.60). The daily hot water use in the test, called its draw pattern, was medium. Its UEF is lower than that of 88 of the 288 gas storage models with its draw pattern. Its UEF is the median for its type and draw pattern. When it reheats water in the test, 77% of the energy it uses ends up in the water.

All of its test figures are shared by 3 other basic models. The AMERICAN STANDARD WATER HEATERS and Lennox brands list one or more of them. For the full group, see the AMERICAN STANDARD WATER HEATERS GSN30T1-3-* page.