Coffee machine water filter
The part that exists to prevent scale, and the manufacturer's descaling procedure begins by taking it out — a step almost no consumer coverage mentions.
Precautions
- Check the manufacturer's instructions
- Rinse thoroughly afterwards
Start here
What this is, what tends to go wrong with it, and what to do about it.
Made from
What tends to go wrong
A hard, chalky calcium carbonate deposit left by hard water. Dissolved by acids, essentially untouched by detergents.
Why it is difficult: Water hardness, Crystallisation, Adhesion and cohesion
- Dustvia its material
Mostly textile fibres and skin, held by static as much as by gravity — which is why a dry cloth on a plastic surface makes it worse.
Why it is difficult: Static and dust, Mechanical action and abrasion, Why different surfaces get different dirt, Surface roughness
A concentrated water-soluble dye with nothing else in it. Nothing has to be emulsified or dissolved — the only question is whether the surface has taken the colour up.
Why it is difficult: Capillary absorption, Dye migration and colour bleeding
A sticky, yellow-brown tar film deposited everywhere at once. It is the reason a room smells after everything visible has been cleaned.
Why it is difficult: Adsorption of odour molecules, Solubility and polarity
Coloured by turmeric in most prepared mustards, and curcumin is a pH indicator — which is why an alkaline cleaner turns a yellow mark red.
Why it is difficult: pH indicators in stains, Fat-soluble pigments, Photodegradation, Pigment retention
The commonest cleaning problem that is not dirt. The tackiness is the plastic's own additive arriving at the surface, which is why wiping it off works for a week.
Why it is difficult: Plasticizer migration, Damage versus soiling
The science behind this: Solvent crazing, Static and dust, Solvents and polymers, Plasticizer migration
Part of Coffee machine.
In detail
Many bean-to-cup machines take a replaceable filter cartridge inside the water tank, which reduces hardness and chlorine before the water reaches the boiler. Two facts about it decide most of the maintenance questions people ask. The first is that it is a consumable with a service life, and a machine that prompts to replace the filter is not malfunctioning. The second is the one the manufacturer states and consumer coverage does not: the filter is REMOVED before descaling and refitted during the rinse sequence. Leaving it in place would mean descaling through the part that exists to prevent scale. The filter is not a substitute for descaling either. It reduces the rate at which scale forms; it does not prevent it, and the manufacturer's water hardness SETTING is what governs how often the machine asks.
Related
- Coffee machine water filter is made from Household plastics
- Coffee machine water filter is commonly affected by Limescale
Sources for this page
Sources
Guide: Descaling — De'Longhi Coffee Machines Help Center
De'Longhi · Manufacturer documentation
Relied on for: That the water tank is removed, the lid lifted and the filter removed if inserted before the descaler is added, and that the water softener filter is put back during the rinse sequence. (states this directly)
Descale light is flashing frequently — De'Longhi Coffee Machines Help Center
De'Longhi · Manufacturer documentation
Relied on for: That the machine's water hardness setting governs how frequently descaling is required. (states this directly)