Limescale in Water

Limescale in water blog

Limescale is a chalky white deposit which is made up of primarily of calcium and magnesium that resides in various water supplies across the UK (and the world)! If you live in a “hard” water area, you are already probably very familiar with limescale and its effects. The main nuances being the white spots which are left on surfaces such as shower screens, work-tops and sinks. Not to mention the potentially devastating coating of heating appliances and blocking up pipes in the home which can lead to increased bills and expensive repairs.

So, what is a “hard water” area?

Hard water is a term used when describing water that contains above-average levels of dissolved minerals and is high in TDS (total dissolved solids). A handy map below shows areas of water hardness across the UK:

You will see the measurement used in the scale is PPM (parts per million). This is the unit used to measure the total mineral content of water.

Limescale in the water is actually considered relatively good for you as the two components – calcium and magnesium are essential minerals. Most mineral water bottles you find in store will contain levels of calcium and magnesium in them.

So, what is the reason for different areas having harder water than others? 

It is all actually to do with the water cycle. When water runs through areas with a large presence of a certain stone or mineral, it then filters through these rocks absorbing those minerals into the supply. You will see that generally; hard water areas of the UK have a higher content of limestone rock and chalk.

So, we have mentioned previously that limescale can be detrimental to your plumbing and your wallet, but how bad can it be?

Limescale theoretically ‘attacks’ any appliance in your home where water would come into contact with any heating element, coating it in the hard-chalky white deposit which is primarily calcium. These include boilers and kettles, and any other appliance where water would come into contact with a heating element such as a coffee machine. This reaction happens at an accelerated rate in high temperatures as the limescale builds up quickest around the hottest parts of heating elements.

Other places where you may find limescale build-up include shower heads, leaks around any taps or water outlets in the home and surfaces such as shower screens and washbasins.

Limescale fouling can also occur in cold environments. The most popular of these being when creating ice, limescale can be extracted from the water leaving ice white and cloudy.

What are the costs?

  • British Water calculated that for every 1.6mm of scale built up in your heating system, there is a 12% loss in heating efficiency.
  • The Carbon Trust found that a 1mm layer of limescale causes a 7% increase in energy input to the boiler to get the same heating result as a boiler free from limescale.
  • This could cost the average household an extra £200 per year in energy costs.
  • When no limescale is present it takes, on average, 90 minutes to heat a tank of water.
  • When 5mm of limescale is present it takes, on average, 4 hours to heat a tank of water.
  • When 10mm of limescale is present it takes, on average, 6 hours to heat a tank of water.

(Source – https://www.scaleguard.co.uk/hard-water-cost.html)

What are the effects of limescale coating heating elements?

Limescale acts as an insulator, so the element it is coating will over time reduce the output of heat. This has a knock-on effect for other factors, including the appliance having to work harder which in turn puts more stress on the unit itself. Another factor would be having to wait longer for the water to heat, as well as having to foot a more expensive energy bill at the end of the month.

So, how do we combat limescale?

Luckily for us, there are many ways to remove limescale or inhibit limescale growth from our water. The two most popular methods and the easiest to acquire would be media-based removal or by using a water softener.

A water softener removes limescale by using ionic exchange. It essentially swaps out the Calcium and Magnesium ions for sodium, which is obtained from the blocks of salt that you have to top the machine up with. A water softener is usually installed on the inlet to the household and is usually plumbed in to service all outlets of the home, including showers and bathroom sinks. The popular option is to leave an untreated line to cater to drinking water taps and then to have a separate under-sink system to treat the tap water.

Media-based limescale removal/inhibition is usually the most common, cost-effective and lowest maintenance option out there. When I say media-based, this means using a media such as polyphosphate or TAC to either eradicate or inhibit scale.

Our systems and filters which remove or inhibit limescale:

Undersink kits –

Deluxe Undersink Kit (Sediment, Chlorine, Limescale Inhibitor, etc…) – https://finersystems.co.uk/product/deluxe-undersink-drinking-water-filter-kit-with-1m-1-micron-rated-finerfilters-fc02-filter-choice-of-tap/

3M AP2 Undersink Kit (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://finersystems.co.uk/product/3m-under-sink-drinking-water-filter-kit-with-ap2-c405-sg-bacteria-rated-filter-choice-of-tap/

Finerfilters Premium Undersink Kit (Sediment, Chlorine, Limescale Inhibitor, etc…) – https://finersystems.co.uk/product/finerfilters-premium-under-sink-water-filter-kit/

Doulton DUO Undersink Kit – (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Erradicator, etc…) – https://finersystems.co.uk/product/doulton-duo-undersink-filter-kit-with-ultracarb-and-cleansoft-filters-tap-and-fittings/

Filters –

Finerfilters FC02 (Sediment, Chlorine, Limescale Inhibitor, etc…) – https://finersystems.co.uk/product/finerfilters-fc02-replacement-filter-for-deluxe-undersink-water-filter-kit/

3M AP2-C405-SG (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://finersystems.co.uk/product/3m-genuine-ap2-c405-sg-fc02-0-5-micron-water-boiler-filter-for-lincat/

Doulton DUO Replacement Filter Pack – (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Erradicator, etc…) – https://finersystems.co.uk/product/doulton-duo-limescale-reduction-replacement-water-filter-pack-1-x-ultracarb-and-2-x-cleansoft-6-months-supply/

Doulton Ultracarb Short Mount (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://www.finerfilters.co.uk/doulton-short-mount-ultracarb-with-scale-inhibitor-ceramic-water-filter-w9123019.html

Doulton Ultracarb M15 (Compatible Franke Mount) (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://www.finerfilters.co.uk/compatible-water-filter-for-franke-02-with-scale-reduction-doulton-m15-ultracarb-si.html

Doulton Ultracarb Pushfit (Compatible Franke Mount) (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://www.finerfilters.co.uk/compatible-water-filter-for-franke-08-doulton-push-fit-ultracarb-si-w9223031.html

Doulton Ultracarb M15 (Compatible Franke Mount) (Sediment, Chlorine, Heavy Metals, Bacteria, Limescale Inhibitor, etc…) – https://www.finerfilters.co.uk/franke-07-compatible-filter-doulton-m15-ultracarb-si-w9142011.html

Limescale Removal Whole House Systems (more coming soon!) –

https://www.finerfilters.co.uk/salt-free-water-softener-limescale-prevention-10in-standard-system.html

https://www.finerfilters.co.uk/salt-free-water-softener-limescale-prevention-10in-jumbo-system.html

https://www.finerfilters.co.uk/finerfilters-no-salt-salt-free-water-softener-alternative-limescale-prevention-10-double-jumbo-system.html

https://www.finerfilters.co.uk/salt-free-water-softener-limescale-prevention-20in-jumbo-system.html