Calmag HV HV400 Is suitable for use with all componets. It will not harm aluminium or other metals. Rquires No neutralisation, Materials treated with Sludge flux remover is unlikey to form a solid mass again. Overdosing the system does not present a problem. HV400 is a flocculent blend that typically used to shift deposits of silt, mud and sand from open drains. HV400 gives the silt particles to buoyancy in water and by putting a small electrical charge on each particle, it cause them repel each other. Materials treated with HV400 are unlikey to form a solid mass again as this enables the silt and sludge content of the heating system to be removed quickly and effectively. You can use this in a powerflush machine as per instruction on the cleaner. Dosing between 250ml (1/4 of a 1Litre bottle). 10 or so minutes after the addition of HV400 it is quite common for noisy pumps to begun quietening down. HV400 can be left in the system for upto 2 weeks without any detrimental effects. HV400 Performance Cleaner is specifically designed for cleaning older central heating systems. It is a non-acid treatment which restores circulation to radiators and pipework. Its ruthlessly efficient formula shifts built-up magnetite sludge, eliminating cold spots in radiators and restoring proper heat distribution. KEY FEATURES Restores systems suffering with circulation problems Eliminates radiator cold spots Prepares older systems for the installation of new components Has a non-acid formula which does not cause pin-holing or leaks Can be used in all types of indirect heating systems, including those containing *For Professional Use Only*