Ariston ENS40H-*

It holds 37 gallons in the test, 3 gallons less than its 40-gallon sold size. Over one hour from a full tank, it gave 51 gallons in the test (its first-hour rating). That is 14 gallons more than its tank holds, since it reheats during the hour. Of 477 electric storage models, 286 give more hot water in the first hour. The median electric storage model gives 55 gallons in the first hour of the test.

In tests, 92% of the energy went to hot water, so its UEF is 0.92. Its test simulated a day of medium hot water use (its draw pattern). Of 297 electric storage models with the same draw pattern, 81 have a higher UEF and 2 a lower one. For its type and draw pattern, its UEF sits at the median. The water took in 98% of the energy used to reheat it (its recovery efficiency).

There are 3 more basic models with the same test figures. Of those, one or more are under the AMERICAN STANDARD WATER HEATERS, Lennox, and Ruud brands. You can find the whole group on the page for the AMERICAN STANDARD WATER HEATERS ENS40H-*.