Manufacturer takes control of limescale prevention with KalGUARD

A large manufacturing and R&D site located in a hard water area in the southeast of England has reduced limescale deposition dramatically on its calorifiers and hot and cold water outlets thanks to KalGUARD, a scientifically-proven electrolytic device from Sentinel Commercial. As a result, energy efficiency, component longevity and cleaning times have been improved greatly, reaping significant financial savings for the manufacturer.

Like 65% of the population in England, the manufacturing site is supplied with hard mains water (defined as water of more than 200ppm total hardness). Until recently the plant had relied on an ‘external-to-pipe’ coil system for its water conditioning needs, however, the system was almost completely ineffective – all water outlets and calorifiers at the site suffered from extensive limescale accumulation. “The old calorifiers are due to be replaced; one has just failed and looking inside I have never seen such a scaled up calorifier in my life,” reported the plant’s water team manager.

Unfortunately, limescale deposits in calorifiers and heat exchange surfaces can reduce energy efficiency significantly – in fact British Water states that just 1.6mm of limescale build-up can increase a heating system’s fuel requirement by as much as 12%. Increased CO2 emissions, inadequate hot water supplies, and component failures are just some of the additional consequences. Sanitary ware, such as taps, wash basins and showers – which are numerous at the site – also suffered from relentless limescale deposits that were difficult and time consuming to clean.

Unsurprisingly, eliminating the limescale problem was a top priority for the site’s FM team, which is charged with asset protection and improving cost efficiencies. After consulting with Sentinel Commercial, the UK’s leading water treatment specialist in the commercial and industrial sectors, a 54mm KalGUARD system comprising a zinc anode, water meter, filter and controller, was selected to deal with the water hardness issues, and was duly installed in November 2013.

KalGUARD permanently ‘conditions’ water in both new and existing systems by dosing it with a very low level of stable zinc via an electrolytic process that uses a zinc anode and a copper cathode. This forces naturally-occurring calcium carbonate crystals to form as soft non-deposit-forming aragonite rather than into hard, deposit-forming calcite (limescale).

Independent tests carried out at Cranfield University have proven KalGUARD’s ability to reduce limescale. Furthermore, electrolytic technology is recommended by the UK Part L Building Regulations Building Services Compliance Guide 2010 (BSCG) for the control of limescale, unlike ‘external-to-pipe’ devices such as magnetic, impulse field and electrostatic technologies, all of which are supported by claims that are difficult to validate.

According to Ian Barnes, Head of Sentinel Commercial, KalGUARD also offers many benefits over other Part L BSCG approved technologies: “We’re seeing a lot of commercial and industrial facilities switching from traditional salt-based water softeners to KalGUARD. Unlike salt-based water softeners KalGUARD doesn’t waste water, doesn’t require salt, and maintenance is minimal. This can save thousands of pounds a year, remove a lot of unnecessary administration, and improve a company’s eco-credentials.”

As the treatment does not decay on standing or agitation, the KalGUARD unit (which is also WRAS approved) can be installed on a rising main before the water storage tanks and booster sets. This means that limescale control can be provided wherever the water is delivered, and both hot and cold flows can be treated by a single unit. Installing KalGUARD on a rising main can also reduce capital expenditure significantly when compared with installing it on a larger distribution pipe – for example, if a location has a 108mm distribution pipe size and a 54mm rising main application feeding a water tank, the savings will be around 65% compared with a standard installation.

Since KalGUARD was installed at the manufacturing and R&D facility, all sanitary wares in the building have remained completely free of limescale, as verified by one of the water team managers who works for the site’s FM company: “I have checked the building’s showers thoroughly and the shower heads are exceptionally clean. There is little to no scale.” As for the calorifiers, there have been no reported limescale issues whatsoever. “This is a great result in a region plagued by the limescale that results from hard water,” concluded Ian Barnes.

Following the success of the first installation, the manufacturer plans to extend KalGUARD protection to other buildings on the site.