TruSeal® Direct Vent and Sealed Combustion Chamber which is 100% Factory Fire Tested with the Efficiency of 85%.The Maximum Outlet Temperature is 210°F and the minimum Non-condensing Inlet Temperature is 105°FThe Heat Exchanger is Thermal Shock Proof and carriers a Limited Twenty-year Thermal Shock Warranty which is Limited Five-year Heat Exchanger Warranty.The Fault Indicator LED's make diagnostics very reliable. The PolyTuf Powder Coated Cabinet is resistant to the elements and no Combustible Floor Shield is Required. The Fan-assisted combustion process contributes to the efficiency and parts4heating is the place to purchase any and all replacement spare parts.