Leak Sealer F4 is a internal leak sealer developed for use throughout a central heating system to seal small, inaccessible leaks and weeps which may cause pressure loss and boiler breakdown. Once dispersed within the system, the product finds the area of oxygen ingress and forms a polymer to seal the pinhole. Effective within 1-24 hours after application, the unique sealing efficiency of this market-leading water treatment chemical has been proven to prevent blockages or restrictions within the boiler or vulnerable system components such as pumps and safety devices. A leak can be quickly and efficiently sealed, without the need for a complete system drain down. The Fernox Express range uses Barrier Pressure Pack technology and compressed air propellent to expel the product so the entire range is non-flammable. The propellent (compressed air) is not mixed with the active product so there is no risk of air ingress into the system which could accelerate future risk of corrosion.
In single feed indirect cylinder, e.g. 'Primatic' or similar, potable water chemicals must be used.
Fernox Leak Sealer F4 Express is supplied in 400 ml aerosol cans with a universal applicator set.
Fernox Leak Sealer F4 Express is classified as non-hazardous, but as with all chemicals: Keep out of reach of children. Do not mix with other chemicals. Do not take internally. In case of contact with eyes or skin, rinse immediately with plenty of water.