Forsbacka Värmeverk was using steam soot blowing in the economizer once every 24 hours prior to the installation of the infrasound generator. The performance of the existing soot blowers was not satisfying and the cost for maintenance of the soot blowing system was considered too high. Soot deposits on the tubes resulted in corrosion of the tubes. The precipitator and all the tube bundles in the boiler needed extensive cleaning at the annual maintenance stop.