A Versatile Gas-Fired Steam Boiler For Your Unique Home. If you need a new gas-fired steam boiler (or for an expert to maintain your existing steam boiler) in the Robstown neighborhood, McNatt Inc is here to help. We offer the Lennox® GSB8-E, which boasts a diverse menu of benefits. GSB8-E BoilerThis steam boiler rises above its competition with an 82.7% AFUE rating* and notable components like a cast-iron heat exchanger and titanium burners. For years of comfortable heat, look at the GSB8-E. Electronic ignition monitors water temperature and lights the burner only when it needs to Vent damper bolsters efficiency by closing automatically when the boiler shuts off Thick fiberglass insulation minimizes off-cycle heat and energy loss Burns natural gas or convertible to LP gas Compatible with traditional radiator and underfloor heating systems Electronic low water cut-off Big steam chest and multiple supply connections reduce noise Available in seven different sizes to fit your home’s individual needs 12-year limited warranty on heat exchanger, 1-year limited warranty on remaining covered parts Efficiency Rating (AFUE): up to 82.7 Product Brochure Contact Us to Learn More McNatt Inc in Robstown is is here to help you with a new high efficiency boiler! Call us at 361-888-4808 or create an appointment online. *Annual Fuel Utilization Efficiency (AFUE) measures how efficient the appliance is in converting its fuel’s energy into heat over the course of a year.