How often to descale a steam generator: the trigger

You are halfway through the school shirts when the calc light starts flashing, and a search result tells you to wait until the first Sunday of the month. Those two clocks cannot both be right. How often to descale a steam generator is the cue on your model: a light, a volume of water, or a calendar figure the brand published as a rule of thumb.

Philips UK support talks in months. On the SteamElite Plus, Morphy Richards waits for about five litres and tells you not to start Auto Clean early. Which? ties a monthly collector rinse to hard water or to ironing more than three times a week, and only if that part is fitted. Tower's page of 9 July 2025 calls once a month a hard-water guideline and still sends you to the manual.

This page decides when you start. The button sequence lives in the how-to. We used those public UK pages and the amazon.co.uk listings on our shortlist. We ran no laboratory descale, and a purchase through our links can earn a commission at no extra cost to you.

In short

How often to descale a steam generator follows the light, the litre count, or the interval written in your manual. A month is a rule of thumb, and Philips, Tower and Which? are not timing the same part of the iron. No UK statute names a day of the month.

There is no single UK interval

There is no single UK interval for how often to descale a steam generator. Each published figure describes that source's own routine. Averaging 'one to two months', 'about five litres' and 'three times a week' into one phone alert does not produce a British standard.

Philips, on its UK descale FAQ, says every one to two months so brown stains and leaks are less likely. Easy De-Calc is tighter: once a month, or more often if necessary. Both lines are about Philips routines. They are not a reason to empty another brand's collector on the first of the month.

Tower's support article of 9 July 2025 calls once a month a guideline in a hard-water area, and tells you to follow the manual. It gives no litre figure and it speaks for no other brand. Soft water, plus a manual that never mentions a calendar, does not turn that sentence into a Sunday job.

Which? is writing about cleaning an iron, with conditions attached. Rinse a limescale collector about once a month if you live in a hard-water area or you iron more than three times a week. Cartridges, where the iron has one, are often replaced about every three months. That is guidance, not a statute, and it applies only when your station has the part being described.

If the manual names a light, a volume or a month, that sentence outranks a blend of these four sources. Our steam generator comparison shows the shortlist. It does not print one descale date for every station on it.

Follow the light or the litres

The calc light is the interval when your station has one. How often that light appears is the maker's count of time or of water. Run the routine it asks for, even when the shirt pile is only half finished.

A steam generator after 5 litres is one model's rule, not a figure for every base on a UK socket. Morphy Richards says the SteamElite Plus runs Auto Clean after about five litres, and not before. If your base has no litre memory, waiting until you think you have used five litres is a guess.

On that SteamElite Plus, a weekend Auto Clean because a blog said 'little and often' leaves the procedure the brand published. A time-based light works the other way. Philips says a reminder can blink on a schedule even when the boiler has little scale.

When the light is on, the interval has arrived, including the week you filled the tank with demineralised water. A flashing symbol, a message on the base, or a collector the manual tells you to empty are all now signals. If there is no light, no month and no litre figure, a rule of thumb is only the backstop.

A month is a rule of thumb

Use a month when the manual is vague and your house matches the conditions that source named. Descale a steam iron every month fits three different jobs, and they are not interchangeable. It is Philips language for Easy De-Calc, where the brand says once a month or more often if necessary. It is Tower's hard-water guideline. It is the Which? limescale collector rinse if the water is hard or you iron more than three times a week.

Giving a cartridge that same monthly soak wastes a part Which? still treats as serviceable for longer. In a hard-water area the gap gets shorter, because Tower and Which? both flag hard water, and Philips allows more often if necessary. Water choice sits on the hard-water steam generator guide.

A family load on most evenings is over the three-times-a-week line, so a monthly collector rinse matches Which? if a collector is fitted. Sunday shirts and soft water do not, on their own, demand a rinse every thirty days.

Distilled water does not switch the light off

You can fill the tank with distilled or demineralised water and still owe the routine. Philips says a time-based light can blink even when you use demineralised water and there is no scale to remove. Finish that routine or the iron may not steam.

Do I descale if I use distilled water? Yes, when the cue says so. Distilled water slows how fast scale forms. It does not delete a timer the station has already started. If the reminder follows water volume, distilled water still counts through the pump. About five litres on the SteamElite Plus is a volume, not a hardness score, and that counter still moves in soft water.

Do not invent a weekly vinegar clean

A weekly vinegar clean feels careful, and it is the wrong interval once a steam generator already has a calc routine. Descaling every Sunday with household vinegar is a habit copied from a basic iron. It answers a different machine from the one on your board.

Morphy Richards tells SteamElite Plus owners not to start Auto Clean before about five litres, so an early Sunday cycle leaves that procedure. Waiting three months lets the Philips window of one to two months, and the Easy De-Calc month, pass. A three-month gap is closer to a cartridge change than to a collector rinse.

This page gives no vinegar recipe, dilution or button sequence. The how to use a steam generator page and our how to descale a steam generator article own the method. Use the collector, cartridge or programme the manual names, on the brand's cue.

Water from the hose or the body of the base is a different fault from a brown flake at the soleplate, and another descale this week will not settle it. The checks sit in brown water, leaks and when to stop. If the station will not heat, book a repair.

What this does not change on the comparison

The interval does not choose the station, and a high score does not write a gap the manual never gave you. The Tefal Pro Express Protect GV9230, ASIN B08XXYC9L8, shares the highest score on that set, 90, with two other Tefal Pro Express Protect listings, so it is the top pick featured here.

We did not descale it in a lab, and the listing is not a timetable for the iron you already own. You can open it on amazon.co.uk. A higher score does not buy a longer gap between cleans. Steam rate, pressure and tank size leave the calc light where the manufacturer put it.

Products Compared is the editorial name on this page, updated in October 2026. The interval sources are Philips UK support, Tower Housewares support dated 9 July 2025, Which?, and Morphy Richards UK support for the SteamElite Plus. When your manual and these pages disagree, follow the manual, then the light or the litres it describes.