For detailed instructions on the cleaning of central heating systems using DS40 System Cleaner, please refer to the instruction leaflet inside the box. The product can be poured as a free-flowing powder directly into a powerflushing unit. Alternatively, by pre-dissolving in warm water, the product can be applied via the FE tank or, in a sealed system, via a Fernox Injector into a radiator. One box (1.9 kg) is usually sufficient to clean a typical domestic central heating system. For large systems and heavily scaled or sludged systems, additional powder may need to be added. During the early part of the clean, a colour change (red-yellow) indicates that the product is exhausted and more powder needs to be added. Once the clean has been completed, add the sachets of System Neutraliser until the solution turns yellow.
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