Leak Sealer F4 10L

Product Code: 62556

Leak Sealer F4 is an internal leak sealer developed for use in HVAC and light commercial heating and cooling systems 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 on vulnerable system components such as pumps, air vents and safety devices. A leak can be quickly and efficiently sealed, without the need for a complete system drain down. One 10 litre product treats up to a 2000 litre system at a dose rate of 0.5%.

  • Silicon emulsion-based formulation designed to migrate to the sides of the pipework to plug microscopic, inaccessible leaks and weeps in HVAC and light commercial systems
  • Eliminates the need for a complete system drain down
  • Proven to be effective within 1- 24 hours after application
  • Resolves pressure loss issues quickly and efficiently with minimal intervention
  • Safe to use – does not cause blockages in pipework or vulnerable boiler components such as pumps, air vents or heat exchangers
  • Disperses quickly within the system to find the area of oxygen ingress and seal the pinhole
Application, Fitting & Dosing

The recommended in-use concentration of the product is 0.5% which will treat a 2000 litre system. Fernox Leak Sealer F4 10L can be introduced into the system via a suitable point such as a dosing pot. To ensure rapid dispersion, partly drain down the system to introduce the required amount of Fernox Leak Sealer F4 10L. The product is effective within 1-24 hours after application and does not need to be removed from the system afterwards.

Package, Handling & Safety

Fernox Leak Sealer F4 is supplied in 10 litre containers.

Fernox Leak Sealer F4 is classified as non-hazardous, but as with all chemicals, keep out of reach of children. In case of contact with eyes or skin, rinse immediately with plenty of water.

Physical Specification / Properties

Fernox Leak Sealer F4 is a polymer emulsion.
Colour: Off white
Odour: Faint
Form: Viscous liquid
pH (conc.): 5.0 – 7.0
pH (in-use): 7.0 – 8.5
SG: 1.0 at 20°C

Volumetrics / Dimensions
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310 × 230 × 205 mm
310 x 230 x 205 mm


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