Ariston GN50T1-3-*

It holds 47 gallons in the test, 3 gallons less than its 50-gallon sold size. It delivers 85 gallons of hot water in the test's first hour. Reheating lets it give 38 gallons beyond the 47 gallons in its tank. In the first hour, 192 of the 763 gas storage models give more hot water. The median gas storage model gives 78 gallons in the first hour of the test.

As of Oct 26, 2026, it was not listed as ENERGY STAR certified. In tests, 63% of the energy it uses ends up as hot water (UEF 0.63). The daily hot water use in the test, called its draw pattern, was high. Of 434 gas storage models with the same draw pattern, 339 have a higher UEF. A UEF of 0.66 is the median for its type and draw pattern. When it reheats water in the test, 84% of the energy it uses ends up in the water.

There are 2 more basic models with the same test figures. Of those, one or more are under the AMERICAN STANDARD WATER HEATERS and Lennox brands. You can find the whole group on the page for the AMERICAN STANDARD WATER HEATERS GN50T1-3-*.