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How to Descale an Espresso Machine

Scale control protects the water system, but not every espresso machine should be descaled at home. Follow the model’s water specification and maintenance instructions; some systems need a qualified technician.

Why scale builds up

Heating water can cause mineral deposits to form, particularly when it contains calcium and bicarbonate. Scale can accumulate on heating surfaces and in water passages. The rate depends on the water chemistry, temperature and use. Hardness, alkalinity and total dissolved solids are different measurements; use the water specifications for your machine.

Signs you need to descale

Reduced flow, weaker steam or unusual heating can have several causes. Follow the machine’s diagnostic instructions instead of assuming scale. If the machine has a descale prompt, use its prescribed procedure. Seek service for unexplained faults or suspected heavy scale.

How often to descale

Use the manufacturer’s schedule or prompt, adjusted as instructed for measured water hardness and use. Filtered water is not necessarily soft water. There is no safe universal interval for every machine.

Descaling vs backflushing

Descaler targets mineral deposits; coffee detergent targets coffee oils. Backflush only if your machine’s manual permits it. Neither product substitutes for the other, and some maintenance belongs with a technician.

The descaling process

Check that user descaling is permitted. Use only the specified compatible product, concentration, cycle and rinse sequence. Do not improvise with vinegar or citric acid, open a boiler, or drain hot pressurised equipment.

Preventing scale with filtered water

Choose treatment that meets your machine’s hardness, alkalinity and other water limits. A carbon filter may reduce chlorine without softening water. Mineral sachets add minerals; they do not filter water. Check the resulting water rather than relying on a brand name.

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