Limescale In Washing Machines

Limescale-damaged-element This page looks at the effects of hard water and limescale in washing machines. Limescale needs to be prevented. Removal products are just dealing with symptoms and can be ineffective if the problem is too bad.

What is hard water?

Hard water is water that has a lot of minerals dissolved in it. The minerals come from the rocks and earth in the area where the water is collected (such as calcium and magnesium salts). It very much depends on where you live as to how hard (or soft) your water is. Soft water conversely has far fewer minerals.

How does limescale and hard water affect washing machines?

The main problem is a build up of limescale on the heating element. This can shorten the life of the element because it acts as an insulator and causes the heating element to get much hotter inside than it should be. This can lead to premature breakdown. A heating element caked in limescale is also less effective at heating water because of the insulating effects.

This means more electricity is used. Limescale can also accumulate in many other places inside the washing machine. It coats the inside of all hoses and surfaces. This can help rot hoses and seals

Finally, with hard water you need to use more detergent to wash the clothes effectively. Clothes washed in hard water can suffer damage to fibres, shortening their life span. Not using enough detergent in hard water areas leads to limescale problems.

How does hard water and limescale affect plumbing and other domestic appliances?

All appliances that heat water are affected by limescale deposits. The life of the heating elements in these appliances can all be shortened. This ranges from the heating element in the hot water tank, to the kettle. Hard water causes staining on certain bath and sinks, clogs shower heads and furs up the insides of pipework in a similar way to how our own arteries get clogged up with cholesterol.

How do I know if I have hard water?

About 60% of UK homes have hard water. I think it’s fairly safe to assume that anyone who has hard water should know about it because of the state of their kettle or the stains in the bath or sinks.

Having said that, you might want to know just exactly how hard or soft your water is. Or maybe you want to find out the state of the water in an area you don’t live in. You can find out how hard or soft the water is by contacting the water company in the area. Water companies are good at providing such information. If you are really interested, most water companies will send you a free water hardness testing pack to test your supply. Choose

Is hard water bad for you?

If anything, hard water is good for you. It may be bad for washing machines, and plumbing, but the calcium and magnesium in drinking water is actually beneficial to us. It may clog up pipework in plumbing, but research has suggested a link between hard water and lower cardiovascular disease mortality. It’s one of life’s ironies that isn’t it? One of the disadvantages of using some full water softener systems is that some of these beneficial minerals are removed.

Do you need to use anti limescale tablets?

Washing machine and detergent manufacturers are well aware of how limescale affects appliances. Therefore washing machine detergent contains essential ingredients to soften the water, which is designed to prevent all these problems and damage.

The problem is many people just don’t use enough, and then have limescale problems. Theoretically, you should not need to use any additional product other than a good quality detergent and the proper dosage for the level of the water hardness. I have a full article looking at anti-limescale tablets and explaining in more detail here – Is Calgon worth using?


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6 thoughts on “Limescale In Washing Machines”

  1. “A heating element caked in limescale is less effective at heating water because the limescale acts as an insulator, which means more electricity is used”

    That actually defies the conservation of energy; if more electricity is used then more heating of the water has taken place.

  2. Hello Anwar, I don’t think more heating of the water occurs other than water is heated for a longer period because the element is not as hot. Some of the electricity used to cause the heater to get hot is wasted because it can’t get heater as hot as it should be. It would be like if we put a insulating cover over a radiator, the radiator would remain as hot inside and continue to use energy, but less of the heat would escape into the room so the room would take much longer to reach temperature.

  3. Annabeth may sowter

    Hello we have a washing machine that uses cold water, but we have limescale and its broken the drum to the point of not spinning.please what can we do

  4. Andy Trigg (Whitegoodshelp)

    Hello Annabeth. Limescale, and grease & slime can build up inside a washing machine to such an extent that it can rot through the aluminium spider on the back of the drum. These days, if that happens most washing machines are not worth repairing. Many have totally sealed outer drums and would need a complete outer and inner drum fitting.

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