TP25-08 The Invisible Source of Lost Heat TransferBiofilm is a hidden cause of lost heat transfer efficiency in heat exchangers and chillers. Surprisingly, few water treatment suppliers are aware of this loss of heat transfer efficiency and dont conduct measurements of the bacteria in the biofilm. Its difficult to control conventional biofilm treatment (non oxidizing biocides) because the water treatment supplier must estimate the chemical dose and feed schedule. There are several methods to measure