Most people in the UK suffer from the problems associated with limescale. Whether that be the added costs and time to clean scaled up fixtures or needing to replace an expensive equipment due to irreparable damage caused by scale. In order to deal with this problem, we need to understand it first. In this article we’ll be taking a straightforward look at limescale and why it forms.
What is limescale
So, what is limescale? Limescale appears as a hard and chalky deposit, firmly bonded to whichever surface it rests on. This build up continues to grow as more calcium is deposited, forming thick layers. The colour of limescale can vary depending on what other minerals may be present. If the water has high iron content the scale will appear reddish-brown, for example.
But if we want to delve a little deeper, we first must touch on water hardness. Hard water is what supplies most UK households either being sourced from aquifers or open water sources. Minerals from these sources end up in your system. It is the mineral content of the water which classifies it as hard, the higher the mineral content the higher the hardness.
The two most common minerals in hard water are calcium and magnesium. It is the calcium, or more precisely calcium carbonate in its calcite form, which is the building block of limescale.
Why does it form?
So why does the calcium carbonate in the water bond to surfaces and form limescale? Without getting too deep into the chemistry, the high temperatures alter a chemical equilibrium in the water causing soluble calcium bicarbonate to become insoluble calcium carbonate. This causes the calcium carbonate to precipitate out of the water and then bond to surfaces forming scale. As we’re sure you’re aware this means that your kettle, boiler and other heating elements are especially susceptible. The same occurs when water evaporates leaving the calcium carbonate behind.
If you would like to a handy description which tackles the subject in a little more detail please head over Compound Interests page on the subject, note it doesn’t cover everything including how systems such as ours help tackle the issue.
What problems does it cause?
Other than the obvious cosmetic issues caused by limescale ruining the appearance of fixtures there are some serious consequences to its formation. The biggest is limescales effect on heating elements. As the scale builds up in these areas their efficiency plummets. For every 1mm of scale built up on a heating element an extra 10% of energy is required for it to function. Eventually the build-up will be so great that the heating element is rendered unusable and will need replacing. This is why expensive pieces of equipment such as boilers break down regularly in areas of high water hardness.
So how do you prevent limescale?
To prevent limescale you have to deal with the source of the problem. The minerals in the water. One way is to remove them completely. This is how salt softeners deal with the issue, changing the hard water to soft. This does however have other consequences in regards to health, plumbing and further expenses.
Another method is to alter the way the minerals behave, preventing them from bonding normally. This keeps the minerals in solution maintaining the positive aspects of hard water without the negatives of scaling. Water conditioners such as the Halcyan deal with limescale in this way.
We hope this was a helpful and straightforward explanation of limescale and its effects. If you would like more detail on how to prevent Limescale issues check out some of our other blogs such as this introduction to water conditioners.