6-year limited Tank warranty, 6-year parts warranty for Residential applications Ultra-Low NOx High Recovery Code Compliance - The Ultra-Low NOx atmospheric vent residential gas water heater meets the thermal efficiency and standby loss requirements of the U. S. Department of Energy and Current Edition ASHRAE/IESNA 90.1. Fully Automatic Controls with Safety Shutoff -Accurate, dependable control system requires no electric connections. Fixed automatic gas shutoff device for added safety. Heavy Gauge Steel Jacket - Finished with baked enamel over bonderized undercoat Blue Diamond® Glass Coating - Provides superior corrosion resistance compared to industry standard glass lining.