The ProLine® standard electric water heater is a reliable 40 gal water heater choice when you are looking to maximize your hot water output and is designed with environmentally-friendly insulation to reduce standby heat loss. With a 40 gal (nominal) tank producing 6000 W, the ESX-40-DONS delivers a first hour rating of 55 gals and a recovery rate of 21 gph. With an 0.92 Uniform Energy Factor, this water heater is not ENERGY STAR® qualified. It carries a 10-year limited tank warranty.