A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports. After that adjustment is made the furnace emissions could be checked for NOx, SOx and particulate emissions and further adjustments could be made to the burners to reduce those emissions.