HCG3-100T199-3NA American Water Heater 100 Gallon 199,900 BTU High Efficiency Commercial Gas Water Heater The full line of American High Efficiency condensing water heaters have been designed to provide years of dependable service and feature industry leading technology. The unique helical coil heat exchanger limits weld joints for optimal service life while maximizing heat transfer.INTELLIGENT CONTROL SYSTEM WITH LCD DISPLAY Exclusive American designed control systemProvides detailed water heater status informationPrecise temperature control adjustable from 90 to 180 degreesBuilt-in diagnosticsRun history information SUBMERGED COMBUSTION CHAMBER, WITH HELICAL HEAT EXCHANGER COIL Positioned in center of tank, surrounded by water to virtually eliminate radiant heat loss from chamberDirect spark ignitionSpiral heat exchanger keeps hot burner gases swirling, uses centrifugal force to maximize efficiency of heat transfer to water in tankSpiral heat exchanger reduces lime scale from forming on water-side surfaces, which maintains energy efficiency over time POWERED ANODES STANDARD ON ALL MODELSProvides long-lasting tank protection in varying water conditionsPowered anodes are non-sacrificialAutomatically adjusts output needed to properly protect the tank GLASS LININGGlass coating is applied using a liquid slush coating technique to ensure uniform coatingHeat exchanger coil is glassed both externally and internally for optimum protection MECHANICAL VENTING VERSATILITYConventional power-venting or direct ventingVents vertically or through a sidewallFront located exhaust and condensate connections allow for easy install and accessVents with low cost PVC Schedule 40 intake and exhaust pipe. Approved for optional CPVC Schedule 40, Polypropylene and AL29-4C stainless steel vent materialsDirect-vent intake and exhaust pipe can terminate separately outside building, or through single opening, using concentric vent assemblyTHERMAL EFFICIENCY : 97 percent