Fernox Central Heating Cleaner (500ml) F3 Protecting your central heating system shouldn't be expensive, which is why we have reduced the price of the Fernox F3 Cleaner 500ml so you can save money in the long term. The Fernox F3 Central Heating Cleaner is a quick and effective cleanser for your central heating system, it removes debris, sludge and scale that allows your heating system to work efficiently. Features and Benefits: Central heating system cleanser Suitable for all heating system metals Can be used with Powerflush Machines Size: 500ml