How to descale a washing machine

A washing machine can look clean while mineral deposits and detergent residue collect in less visible areas. If your home has hard water, those deposits may form more quickly. Descaling is a maintenance process aimed at the machine itself, not the clothes inside it.

What is washing machine scale?

Hard water contains dissolved minerals. When water repeatedly enters, heats and drains from an appliance, some mineral residue can remain on internal surfaces. Over time this is commonly described as limescale or hard-water scale.

Detergent residue and trapped moisture can be part of the same maintenance problem, but they are not identical to mineral scale. That is why products labelled “cleaner” and “descaler” can have different primary purposes.

Signs your machine may need attention

• A stale or musty smell remains after ordinary laundry cycles.
• Visible chalky residue appears around accessible water-contact areas.
• The manufacturer’s maintenance indicator or schedule says a cleaning cycle is due.
• Your household uses hard water and routine appliance care has been irregular.

Descaler vs washing machine cleaner

Choose based on the main problem:

• Descaler: the more focused option for limescale and hard-water mineral build-up.
• Washing machine cleaner: broader drum and tub care for dirt, detergent residue, odour and some limescale.
• Laundry detergent: designed for clothes, not an empty-machine maintenance cycle.

A safe, label-first descaling routine

1. Read two sets of instructions

Check both the descaler label and your washing machine manual. The appliance maker may specify a maintenance cycle, temperature, compartment or product restriction.

2. Empty and inspect the drum

Remove all laundry and foreign objects. If the manual asks you to clean a filter or gasket separately, follow those instructions.

3. Add only the directed amount

More product is not automatically better. Use the quantity and location stated on the label. Do not mix cleaning chemicals unless both labels explicitly permit it.

4. Run the recommended empty cycle

Select the machine-cleaning or maintenance cycle named in the appliance manual. If your machine has no dedicated option, use only the alternative the manufacturer recommends.

5. Finish and ventilate

Complete any rinse or wipe-down required by the instructions. When safe for your household, leaving the door or lid open briefly can help the interior dry.

How often should you descale?

There is no single frequency for every home. Water hardness, number of weekly washes, wash temperatures and the manufacturer’s schedule all influence the right interval. Use the appliance manual as the primary rule and adjust only within the product’s directions.

How to reduce future build-up

• Use laundry detergent in the amount recommended for your water and load.
• Remove wet laundry promptly so moisture does not sit in the drum.
• Keep accessible seals and detergent compartments clean according to the manual.
• Make machine maintenance a visible household reminder rather than waiting for odour.