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Fernox F4 Central Heating Leak Sealer 500ml

Item Code: 354960339

Fernox F4 Central Heating Leak Sealer 500ml
£18.85Ex VAT£22.62 Inc VAT
Click & CollectAvailable for collection
DeliveryFree delivery available (restrictions apply)
Seal small, inaccessible leaks and weeps in a central heating system with Fernox F4 Leak Sealer. There is no need to drain down the system before use, and once dispersed, it will be effective 1 to 24 hours after application.


  • Ideal for reducing pressure loss from sealed systems
  • Proven to seal most weeps and small inaccessible leaks
  • Time saving - no need to drain down the system
  • Does not cause blockages of pumps and air vents
  • Compatible with all metals and materials used in heating systems
  • Can be left in the system permanently
Volume (Litres)500ml
Data SheetsConversion & Materials Calculator

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