The ProLine® Ultra-Low NOx gas water heater delivers an efficient, reliable performance and features an innovative design that protects against accidental ignition of flammable vapors.

AO Smith® ProLine® Gas Water Heater, Series: GUC-50, 40000 Btu/hr Heating, Natural Gas, 1/2 in Gas Connection, 50 gal Tank, Piezo Pushbutton Ignition, Atmospheric Vent, 3 in, 4 in Vent, 42 gph at 90 deg F Recovery, Energy Factor: 0.6, 3/4 in Water Connection, 150 psi, Tall or Short: Tall, Ultra Low Nox: Yes, 20 in Dia x 60 in H

• Intelligent control logic - The internal microprocessor provides enhanced operating parameters and tighter differentials for precise sensing and faster heating response to optimize performance
• Uses a thermopile to generate the power needed to operates the electronic gas control without requiring an external power source
• The electronic gas control incorporates an LED status indicator that monitors system operation and service diagnostics
• High energy factors - Eco-friendly non-CFC foam insulation, heat traps and specially designed combustion chamber combine to produce a high energy factor for maximum savings on operating costs
• Green choice® gas burner enhanced Ultra-low NOx burner complies with SCAQMD rule 1121 and other air quality management districts with similar requirements for Nox emissions of less than 10 NG/J
• Dynaclean™ diffuser dip tube - Helps reduce lime and sediment build up and maximizes hot water output, made from long-lasting PEX cross-linked polymer
• Coregard™ anode rod - Our anode rods have a stainless steel core that extends the life of the anode rod allowing superior tank protection for longer than standard anode rods
• Pushbutton piezo ignitor makes lighting pilot fast and easy with one-hand pushbutton spark ignition
• Heat trap nipples Factory installed for faster installation
• Blue Diamond® glass coating - Provides superior corrosion resistance compared to industry standard glass lining
• Enhanced-flow brass drain valve - Our residential water heaters have a solid brass, tamper resistant, enhanced-flow, ball type, drain valve
• Uses a standard female hose fitting that allows for fast and easy draining during maintenance
• Designed for easy operation, this valve includes an integral screwdriver slot that features a 1/4 turn (open/close) radius, which not only permits full straight-through water flow but also a quick and positive shut off
• Approved for installation from sea level to 7700 ft elevation

• Catalog https://www.hirsch.com//ASSETS/DOCUMENTS/ITEMS/EN/AO_Smith_100051462_Catalog.pdf
• Instruction/Installation Manual https://www.hirsch.com//ASSETS/DOCUMENTS/ITEMS/EN/A_O_Smith_GUC3000L010G41_Manual.pdf
• Specification Sheet https://www.hirsch.com//ASSETS/DOCUMENTS/ITEMS/EN/A_O_Smith_GUC3000L010G41_Specification_Sheet.pdf