Guide · Descaling and cleaning
How to descale a Melitta Purista step by step
When the descaling light comes on a Melitta Purista bean-to-cup machine, here's how to run the descaling programme from Melitta's own UK manual, what you need and how often to do it.
If the descaling symbol on your Melitta Purista has lit up, the machine is asking for its descaling programme. This guide covers how to descale Melitta Purista machines (the Series 300, sold in the UK as the F230101 in silver and the F230102 in black). The programme takes about 25 minutes and needs Melitta’s ANTI CALC liquid descaler. We haven’t tested this in person. Everything below comes from the Purista Series 300 operating instructions linked from Melitta UK’s manuals page, read on 3 Oct 2026. Read how we compare.
How to descale Melitta Purista: the short answer
- Take out the water filter if you use one, and stand it in a jug of tap water.
- Hold the Service button for more than 2 seconds, tap it until the descaling symbol shows, then hold it again for more than 2 seconds to start.
- Empty the drip tray and grounds container when asked, then put 0.5 litres of descaling fluid in the tank.
- After about 20 minutes, empty the tray again, rinse the tank, fill it with fresh water and let the machine rinse itself.
Who it isn’t for: owners of other Melitta ranges, which have their own manuals.
When the Purista asks for descaling
The descaling symbol lights up when the machine wants descaling. To avoid damage, Melitta recommends descaling every 3 months, or whenever the machine asks, unless you regularly use a water filter.
How often the light comes on depends on the water hardness you’ve set (see below). Melitta’s troubleshooting table also lists limescale as one cause of coffee only dripping from the spout.
What you need
- Melitta ANTI CALC liquid descaler. The manual says to use only this, warning that unsuitable descalers can damage the machine. A 250ml bottle was £5.99 at Melitta UK, checked 3 Oct 2026, and shown as in stock. See it at Melitta UK. Follow the bottle’s instructions to make up the 0.5 litres of fluid.
- A jug of tap water for the water filter, if one is fitted.
- About 25 minutes. Melitta says the programme shouldn’t be interrupted.
Melitta also warns that descaler can irritate eyes and skin, so follow the safety notes on the pack.
How to run the descaling programme, step by step
These are Melitta’s steps, in our own words. The machine needs to be on and ready. Coffee bean symbols show which stage you’ve reached, and the descaling symbol flashes until the end.
Before you start
- Remove the water filter. Melitta says a filter left screwed in during descaling can be damaged. Unscrew it from the base of the tank and stand it in tap water.
Stage 1: start the programme (one bean lit)
- Open Service mode. Press and hold the Service button for more than 2 seconds.
- Find the descaling function. Press the Service button briefly, as many times as needed, until the descaling symbol appears.
- Start descaling. Hold the Service button for more than 2 seconds.
- Empty the drip tray and grounds container when the drip tray symbol lights up, then put the drip tray back.
- Add the descaling fluid. When the water symbol lights up, take out the tank, pour in 0.5 litres of descaling fluid and refit it.
Stage 2: let the descaler work (two beans lit)
- Wait about 20 minutes while the descaler works. The machine runs several rinses.
- Empty the drip tray and grounds container when asked, then put the drip tray back.
Stage 3: rinse (three beans lit)
- Rinse the tank. When the water symbol lights up, take out the tank, rinse it thoroughly and fill it with fresh water.
- Refit the tank. Hot water runs into the drip tray.
- Finish off. Empty the drip tray when asked, then refit it with the grounds container. The descaling symbol goes out and the machine is ready to use.
- Refit the water filter if you took one out.
Who this isn’t for: anyone hoping to use a home remedy. Melitta’s manual only approves its own ANTI CALC liquid descaler.
What to do if descaling gets interrupted
If the machine is switched off part way, Melitta says to switch it back on and carry on from emptying the drip tray and grounds container (step 8 above). It will then work, but may not be fully descaled, so run the whole programme again from the start to finish the job.
Water hardness and the water filter
The hardness setting decides how often the Purista asks for descaling. Melitta lists four levels: soft (descale after 150 litres), medium (100 litres), hard (70 litres) and very hard (30 litres). A test strip comes in the box, and you set the level in Service mode 1.
With a Melitta Pro Aqua filter fitted and changed regularly, the manual says descaling once a year is enough, based on 6 drinks of 120ml a day and 6 filter changes a year. Melitta recommends a new filter every 2 months, or when the filter symbol lights up. With a filter in, the hardness is set to soft automatically.
A Pro Aqua filter cartridge was £10.99 at Melitta UK, checked 3 Oct 2026. See it at Melitta UK.
Descaling isn’t the same as cleaning
The Purista has a separate 15-minute cleaning programme for coffee oils, using a Melitta PERFECT CLEAN tablet in the brewing unit. Melitta recommends it every 2 months, or when the clean symbol lights up, plus rinsing the brewing unit weekly. PERFECT CLEAN cleaning tabs were £5.99 at Melitta UK, checked 3 Oct 2026. See them at Melitta UK.
What the Purista costs right now
Still deciding? The silver Purista F230101 was £299.00 at Currys, checked 3 Oct 2026, prices can change. See it at Currys. The black F230102 was £349.00 at Currys, checked 3 Oct 2026. See it at Currys. Melitta UK lists a 1.2 litre tank and 20cm width.
Downsides to know about
- Melitta’s descaler only. Currys listed no Melitta descaler when we searched on 3 Oct 2026, so Melitta UK may be the simplest place to buy it.
- Stay nearby. You’ll need to empty the tray and refill the tank during the 25 minutes.
- The filter has to come out, which is easy to forget.
Where to go next
- Other brands: Siemens EQ300 calc’n’clean, Krups Sensation calc mode and how to descale a Philips 5400.
- A bigger Melitta: our Melitta Barista TS Smart review.
- Still choosing? See our bean-to-cup machines.
FAQ
How long does it take to descale a Melitta Purista? About 25 minutes, according to Melitta, with around 20 minutes of that for the descaler to work.
How often should you descale a Melitta Purista? Every 3 months or when the machine asks, says Melitta, or about once a year with a regularly changed Pro Aqua filter.
Do you need to take the water filter out? Yes. Melitta says to remove it before descaling and keep it in tap water, then refit it afterwards.