Rheem PROPH50 T2 RH375-15

It holds 45 gallons in the test, 5 gallons less than its 50-gallon sold size. It delivers 52 gallons of hot water in the test's first hour. Its tank holds 45 gallons, so reheating adds 7 gallons during the first hour. Of 481 heat pump models, 439 give more hot water in the first hour. The median heat pump model gives 72 gallons in the first hour of the test.

All 5 of its model numbers are ENERGY STAR certified. For each unit of energy it uses, 3.75 units end up in the hot water (its UEF). A UEF above 1 is possible because it moves heat from the air into the water. Its test ran at the medium level of daily hot water use. Among 226 heat pump models on its draw pattern, 59 have a higher UEF. On its draw pattern, the median heat pump UEF is 3.68. When it reheats water in the test, the water gains 423% of the energy it uses.

It is sold under 5 model numbers in all. Its test figures match those of 10 other basic models. Of those, one or more are under the Friedrich, Richmond, and Ruud brands.

In 20 states, 21 rebate programs may accept it. It may qualify for 7 more if it meets terms its figures do not show.