State has introduced the ProLine® XE Non-Powered Damper—the first high efficiency gas product that does not require electricity. This product uses an inlet air damper underneath the combustion chamber that operates using gas pressure. This damper reduces airflow through the heater during the off cycle or when water is not being heated. This increases efficiency, allowing these heaters to be listed as ENERGY STAR® qualified product.
Featuring a 40-gallon (nominal) tank and a 40,000 BTU gas burner, the GS6-40-BDHT standard vent delivers a first hour rating of 82 gallons and a recovery rate of 40 gallons per hour. With an 0.68 Uniform Energy Factor, this water heater is ENERGY STAR® qualified. It carries a 6-year limited warranty.