- Delivers 81-gallon first hour rating
- 40,000 BTU input atmospheric vent design delivers up to 0.64 Uniform Energy Factor
- Ultra-Low NOX Green Choice® Gas Burner, meets or exceeds emission requirements in California & Utah
- Push-button piezo ignitor makes lighting pilot fast & easy
- Patented Blue Diamond® glass tank lining protects against corrosion
- DynaClean™ automatic cleaning system protects against sediment build-up
- Stainless steel CoreGard™ anode rod protects against corrosion longer than ordinary anodes
- 8-year limited tank and parts warranty
The ProLine® Master 40-Gallon Ultra-Low NOx Atmospheric Vent Tall Natural Gas Water Heater delivers an efficient, reliable performance and features an innovative design that protects against accidental ignition of flammable vapors. Featuring a 40-gallon (nominal) tank and a 40,000 BTU gas burner, the HUR-40 Standard Vent delivers a first hour rating of 81 gallons and a recovery rate of 41 gallons per hour. It carries a 8-year limited tank warranty, and meets Ultra-Low NOx emission requirements. Environmentally-friendly insulation and factory-installed heat trap nipples reduce heat loss for maximum energy savings. This ProLine® Master water heater is designed with A. O. Smith's superior commercial-grade tank protection. Advanced tank features include stainless steel CoreGard™ anode rod, Blue Diamond® glass lining and DynaClean™ automatic sediment-cleaning system, all designed to help protect the tank from the corrosive effects of water and extend the life of the water heater. A. O. Smith’s ProLine® water heaters are residential products built to commercial-grade standards and are only available for purchase through professional wholesalers and contractors.