descale

Descale is the process of removing mineral deposits, or scale, that accumulate on the inner surfaces of equipment that handle water in hard-water areas. Scale is primarily composed of calcium and magnesium salts that precipitate when water is heated or its carbonates become insoluble. Descaling is necessary to restore heat transfer efficiency, maintain flow, prevent clogging, and extend the life of appliances and piping.

Common targets include household appliances such as kettles, coffee makers, espresso machines, dishwashers, washing machines, and heating or hot-water pipes and boilers. Regular descaling can improve performance, reduce energy consumption, and prevent premature wear due to overheating or restricted flow.

Descaling methods include chemical descalers (acid-based solutions such as citric acid, sulfamic acid, or acetic acid), mechanical cleaning (scrubbing, scraping, or brushing), and, in industrial settings, ultrasonic descaling. The chosen method depends on the device, material compatibility, and the severity of buildup.

Procedure generally involves applying or circulating a descaling solution through the appliance or system for a prescribed dwell time, followed by thorough rinsing with clean water until residues are removed. Some devices require multiple cycles or a combination of circulating and soaking steps. Always follow manufacturer instructions for chemical compatibility and final rinsing.

Safety and environmental considerations include handling acids carefully, using gloves and eye protection, avoiding mixing descalers with bleach or ammonia, and disposing of spent solutions according to local regulations. To minimize future scale, consider water-softening options or regular maintenance based on water hardness and usage.

See also limescale, water hardness, appliance maintenance.