The Piezo ignition system of the GE 29-gal. 32,000 BTU Natural Gas Water Heater offers convenient, match-free ignition. The low-NOx burner provides powerful heating and helps you reduce your energy emissions. This low-maintenance heater has a combustion air intake that saves you the effort of cleaning and replacing filters. A SmartShield sensor system has an exclusive air/fuel shut-off device that gives double protection against the ignition of flammable vapors.