Tronic electric tankless water heaters offer up to 99% efficiency with a variety of installation options and configurations. These point-of-use units eliminate wait time for hot water as well as piping heat losses, the company says. The Tronic 3000 series is for under-sink applications while the Tronic 5000 is powerful enough for entire-home hot water production. Both come standard with a limited 10-year warranty. 866.330.2725.