Fernox Cleaner F3 should ideally circulate through the system for at least one hour, or up to a week. Afterward, it should be drained, and the system flushed and cleaned before adding Fernox Protector F1 or Protector + Filter Fluid, together with a Fernox TF1 Filter, to protect the system from further corrosion and scale formation.
Do I still need to perform a laboratory test?
BS 7593:2019 recommends that the inhibitor should either be re-dosed at 5-year intervals or, a more comprehensive laboratory test is conducted every five years to provide a more in-depth analysis, and where needed, establish targeted action to resolve issues and restore system efficiency. The Fernox Water Quality Test includes everything needed to take a sample of the system water and



















