Ruud PROG29-32N RH63 *

It holds 28 gallons in the test, 1 gallon less than its 29-gallon sold size. Over one hour from a full tank, it gave 63 gallons in the test (its first-hour rating). Its tank holds 28 gallons, so reheating adds 35 gallons during the first hour. In the first hour, 655 of the 763 gas storage models give more hot water. The median gas storage model gives 78 gallons in its first hour.

On Oct 26, 2026, this heater was not listed as ENERGY STAR certified. In tests, 60% of the energy it uses ends up as hot water (UEF 0.60). Its test simulated a day of medium hot water use (its draw pattern). Of 288 gas storage models with the same draw pattern, 88 have a higher UEF. On its draw pattern, its UEF is also the median gas storage UEF. When it reheats water in the test, 74% of the energy it uses ends up in the water.

There are 3 more basic models with the same test figures. Of those, one or more are under the Friedrich, Rheem, and Richmond brands. You can find the whole group on the page for the Rheem PROG29-32N RH63 *.