Descaling a coffee machine: a simple, regular method

A coffee machine that flows more slowly, makes more noise or whose coffee loses flavor is almost always a victim of limescale. Heating water deposits crystals on the heating element and in the circuits, which reduces the flow, degrades the aroma and can cause irreversible breakdowns. Descaling your coffee machine is simple, takes only a few minutes and should be done regularly, depending on the type of appliance and the hardness of your water.

How often to descale

In hard water (northern and eastern France, for example), descaling every two months is required; in soft water, every three to four months is enough. Espresso and bean-to-cup machines, whose circuit is narrow and hot, foul faster than percolators. Most modern appliances even display a "descaling" light or message when the time has come.

The materials needed

• A specific coffee machine descaler (the most effective and risk-free)
• Or white vinegar (diluted to 1/3 with water) as an economical stopgap
• A container large enough to catch the water (carafe, bowl)
• Clean water for the rinses
• A soft cloth to wipe the outside and the reservoir

Descaling an automatic or espresso machine

1. Empty the reservoir and fill it with the diluted dose of descaler (follow the proportions in the manual)
2. Place a container under the nozzle (and under the steam wand if your machine has one)
3. Run the descaling program if the appliance offers one, otherwise run out half the reservoir
4. Let the product work for 15 to 30 minutes without touching the machine
5. Run out the rest of the reservoir, then discard the water from the container
6. Rinse: fill the reservoir with clean water and run 2 to 3 full cycles to remove all product residue

Descaling a percolator or pod machine

For a percolator, pour the descaling solution into the reservoir and run the water out until empty, spending extra time on the steam function if the appliance has one. For a pod machine, remove the pod holder and circulate the liquid through the circuit before rinsing thoroughly. Also think about soaking the filter holder and the metal filter in a bowl of hot vinegar to clean the mesh.

White vinegar or a specific product: which to choose

The specific descaler is designed to dissolve limescale without attacking the seals, soft hoses and valves of your machine. White vinegar, much cheaper, is an acceptable alternative as a stopgap, but it is more aggressive in the long run and its smell can soak into the circuits. For an expensive bean-to-grind machine, the specific product recommended by the manufacturer remains the safest choice, even if it costs a few euros more per year.

Softening your water to descale less often

The descaling frequency depends directly on the hardness of your water, measurable with a simple test strip sold at garden centers or supermarkets (above 20°f, the water is considered hard). Using a filter jug, an integrated cartridge or a lightly mineralized bottled water noticeably reduces deposits: you will descale less often and your coffee will gain in roundness, because limescale masks the aromas.

Be careful however: pure demineralized water is not recommended for everyday use, because it no longer provides the minerals needed for the proper operation of certain appliances and can accelerate corrosion. Filtered water, neither too hard nor too pure, remains the ideal balance for the machine's longevity and extraction quality.

Special case of capsule machines

On capsule machines, descaling follows the same principle, but the product must pass only through the water circuit, never through the capsule compartment. Remove the capsule holder and the tray, then run hot water cycles with the descaler before rinsing thoroughly. Some machines require using only the brand's product: follow the manual so as not to reset the descaling counter wrongly.

The mistakes to avoid

• Using pure vinegar without dilution: it attacks the seals and leaves a stubborn taste
• Forgetting the final rinse: descaler residue ends up in the cup
• Descaling dry: the reservoir must always contain liquid during the cycle
• Neglecting descaling until breakdown: the fouled heating element heats poorly and the appliance can jam

Regular descaling, even brief, extends the life of your machine, maintains the ideal water temperature for extraction and fully preserves the aroma of your coffee. Simply add this task to your household maintenance calendar, like the vacuum filter or the dishwasher seals.