Gridless AYHW50G

It holds 47 gallons in the test, 3 gallons less than its 50-gallon sold size. Starting full, it gives 69 gallons of hot water in its first hour of use. Its tank holds 47 gallons, so reheating adds 22 gallons during the first hour. Among 481 heat pump models, 263 have a higher first-hour rating. Among heat pump models, the median first-hour rating is 72 gallons.

The single model number sold under it is ENERGY STAR certified. In the test, it delivered 3.75 units of hot water energy for each unit used (its UEF). A UEF above 1 is possible because it moves heat from the air into the water. In the test, daily hot water use was set to medium (its draw pattern). Its UEF is lower than that of 59 of the 226 heat pump models with its draw pattern. On its draw pattern, the median heat pump UEF is 3.68. When it reheats water in the test, the water gains 430% of the energy it uses.

There are 19 more basic models with the same test figures. In all, 17 other brands list one or more of them. You can find the whole group on the page for the 1HVAC ACIQ-50G-HP-WH.

It may qualify for 21 rebate programs in 20 states. Another 7 rebate programs may accept it if it meets their other terms.