For use in domestic heating systems for sealing small inaccessible leaks. Quick and convenient, doses in only 30 seconds. Works best in warm / hot circulating water. Once dispersed evenly in the system water it is effective within 1-24 hours. The sealing...

Internal leak sealer developed for use throughout a central heating system to seal microscopic, inaccessible leaks and weeps which may cause pressure loss and boiler breakdown. Saves time and money on draining down the system and repair costs. Does not...

Fernox Leak sealer 500ml.This leak sealer seals inaccessible leaks and weeping joints internally and is suitable for all metals.