Fernox 61027 Limescale Remover DS-3 2Kg Using sulphamic acid, this powerful but environmentally friendly product is ideal for use to remove baked-on limescale deposits from domestic appliances and boiler heat exchangers. Designed with the consumer in mind, the product is safe and easy to use; after each application the product changes colour to indicate when DS-3 is exhausted and ready for disposal to foul drain. Application and Dosage Fernox DS-3 should first be dissolved in hot water at the maximum concentration of 1 kg per 10 litres of water (10%) with a minimum in-use concentration of 250g per 10 litres of water (2.5%). Hot water will accelerate de-scaling but do not exceed 80 C. The de-scaling process will release carbon dioxide gas (CO-2), which can cause foaming. Hence, space should be allowed for this before commencing work.
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