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Scale Control

The formation of scale on heat exchange surfaces, internal pipework and showerheads is a major water treatment issue. Across most of the UK, untreated mains water contains calcium and magnesium that, once heated or evaporated, creates the scale that we will all have seen inside our kettles.

The presence of scale causes a number of operational issues, as detailed below:

   Reduced energy efficiency 

   Bacteriological growth

   Premature plant failure 

   Loss of flow 

   Increased maintenance 

   Unsightly appearance on fittings 

A 1mm layer of limescale will increase energy costs by 7.5%, while a 12mm layer will raise energy costs by 65%. In serious cases, water temperatures required for compliance with HSE guidelines may not be achieved.

Scale also provides nutrients and breeding grounds for bacteria such as legionella and pseudomonas to thrive. HSG274 (the HSE guidance document on the control of legionella) repeatedly states the importance of controlling scale formation to help control microbiological activity.

Over time, scale build-up will shorten the life expectancy of plant such as water heaters and valves, and can cause significant flow reductions when formed on intenal pipework surfaces and valves.

All of this leads to increased running costs and the need for more maintenance such as descaling of showerheads and water heaters - all to cope with the unsightly appearance of scale and the effects it has on our systems and in extreme cases - human health.

What types of water treatment equipment can be used to minimise issues caused by scale formation?


Water Softening

The traditional and only guaranteed method of preventing scale formation, water softeners operate by removing the dissolved calcium and magnesium within the water and replacing it with sodium.

In doing so, it ensures that scale cannot be created because the minerals that are required are no longer present. It is a reliable, proven method of treatment and strongly recommended for critical applications.

Water softeners can be quite large and do incur ongoing costs in the form of the need for salt to operate as well as regular servicing.

Due to the increased amount of sodium present in the water following treatment, it is inadvisable to use softened water for drinking water purposes.

The operation of our Pegasus range of water softeners can be enhanced with the use of a number of accessories, such as low salt alarms and hardness monitoring.


The main benefits of using a Water Softener are as follows:

  • Only guaranteed method of ensuring a water system is completely free from scale
  • Brass, mechanical valve heads offer reliable performance and longevity
  • Range of accessories available to enhance performance and provide peace of mind

Physical Water Conditioning

In recent years, largely due to space constraints making the installation of water softeners impractical in some buildings, there has been an increased trend in the use of physical water conditioners to alleviate scale related issues.

While there are a number of different types of water conditioners available, the general principle is to generate a significant number of differing polarity fields to, essentially, create scale in a more manageable form that does not cause any of the operational problems described above. The scale that is now present is much finer and ‘softer’ than untreated scale and tends not to stick to heat exchange surfaces, pipework or showerheads.

This treatment is fragile and temporary, being affected by turbulence and typically no longer present after 48 hours. Therefore, the location of these units, as well as the number required, will need to be considered on a job-by-job basis.

Our range of Mediagon physical water conditioners are market leading, having been installed in hundreds of recognised buildings in the UK over the last 20 years, and do not require a power supply or any ongoing maintenance.

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The main features and benefits of our Water Conditioner range are as follows:

  • Compact treatment that requires no floor space
  • Operates without a power supply
  • Cost effective and low maintenance
  • Treated water is suitable for drinking
  • High number of electrostatic field changes provides good quality treatment


More information on hardness and scale can be found in BS EN 806-4:2010 and also -

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Contact us today to chat through your requirements

Our team can provide solutions including any or all of the above services and products to solve your problems and make a difference to your business whilst making sure you are fully compliant in all regards.