Suburban 6 Gal. Water Heater Pilot IgnitionHeated water attacks all metals, but not porcelain. That's why Suburban uses a porcelain lined, steel water heater tank with an anode rod to "absorb" the electrolytical action just like your water heater at home. In fact, when a Suburban porcelain lined tank is properly maintained, tank life may double or triple its 3 year limited warranty, saving owners the cost of premature replacement. In addition, every Suburban tank is pressure tested twice