Ariston PV50TLN*-65*

It holds 47 gallons in the test, 3 gallons less than its 50-gallon sold size. Starting full, it gives 107 gallons of hot water in its first hour of use. That is 60 gallons more than its tank holds, since it reheats during the hour. Among 763 gas storage models, 77 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 tests, 71% of the energy it uses ends up as hot water (UEF 0.71). The daily hot water use in the test, called its draw pattern, was high. Its UEF is lower than that of 105 of the 434 gas storage models with its draw pattern. For its type and draw pattern, the UEF runs from 0.61 to 0.90. When it reheats water in the test, 82% of the energy it uses ends up in the water.

All of its test figures are shared by one other basic model. That one is listed under the AMERICAN STANDARD WATER HEATERS brand. For the full group, see the AMERICAN STANDARD WATER HEATERS PV50TLN*-65* page.

It may qualify for 2 rebate programs in 2 states.