Normally a treatment will last the life of the system but an annual check to determine whether further dosing is necessary is recommended.
If the system is drained, it will need to be re-treated with a further full dose of Protector. You can check if the system is properly dosed using a Fernox Protector Test Kit.
Yes, Fernox Boiler Noise Silencer F2 is designed for use with any Fernox Protector. It should be left permanently in the system with Protector F1 or Protector + Filter Fluid and replaced or topped up at the same time.
Systems should be cleaned when commissioning a new system or installing a new boiler within an existing system. The purpose of cleaning and flushing is to remove mineral oil, harmful flux residues and installation debris which can cause corrosion. Cleaning existing systems removes magnetite (black iron oxide), haematite (red iron oxide) and limescale improving the circulation and reducing fuel wastage
You should only drain central heating system water into the foul water drain or a septic tank. Never drain system water into road drains or rain water gullies as these go directly into rivers. Never pour water from a central heating system onto the garden or lawn.
