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A brand-new police authority headquarters in the Midlands has had its closed, low temperature hot water system saved from potential failure thanks to DosaFil-Duo.

DosaFil-Duo is a unique conditioning device that combines solid or liquid chemical treatment dosing with constant side stream filtration and continuous air removal.  

This patented technology is providing an economical and convenient alternative to powerflushing by cleaning and protecting the system online. DosaFil-Duo was installed after Anker Elemental, a fast-growing water treatment specialist contracted on the site, discovered there were harmful levels of contaminants within the system’s circulating water.

Despite being only recently installed, the hot water system, which controls ambient temperature in the building, contained extremely poor quality water, as Ian Looms, Managing Director at Anker Elemental, explained: “The water’s pH was wrong, it was full of suspended metal solids and so on. In-depth testing revealed that the system had not been cleaned correctly, or possibly at all, while the inhibitor concentration was insufficient. 

“It was also apparent that water treatment had not been maintained in the lengthy period between completion and handover. These conditions are likely to lead to serious problems such as accelerated corrosion, blocking of the system’s control valves, and even complete system failure.” 

In the absence of correct system cleaning and flushing, contaminants, such as flux residues, installation debris, and greases and oils from manufacturer components, will remain in system water. Such impurities not only cause corrosion but prevent subsequently dosed inhibitor from working effectively. Furthermore, water treatment, even when applied correctly, must be maintained to ensure lasting protection.

The first step in Anker Elemental’s remediation programme was to clean the system. Traditionally, the company may have chosen powerflushing for this purpose, however, DosaFil-Duo presented a better solution.

Looms said: “It is our role, as custom water treatment specialists, to devise programmes that ensure the safe and reliable operation of critical systems while minimising energy, water and maintenance costs for our clients. In this case, powerflushing would have necessitated the opening of every valve on the system, all of which are behind wall panels. This would have been an extremely expensive endeavor and incredibly disruptive, potentially requiring large parts of the building to be shut down, a situation that is far from ideal for a police headquarters where operational continuity is imperative.

“DosaFil-Duo, on the other hand, enables commercial and industrial systems that are fouled with corrosion, limescale and harmful deposits to be cleaned up online (filtration is possible to 0.5 microns). By installing DosaFil-Duo, we eliminated the need for costly and inconvenient offline cleaning, and made it possible to optimise the energy efficiency, performance and longevity of the system, as well as minimise unplanned maintenance and system downtime. DosaFil-Duo was the obvious choice.”

Once installed on the system – a process which took less than a day as DosaFil-Duo removes the need for separate bypass chemical feeder, auto air vent and filtration devices – the DosaFil-Duo was dosed with BSK100, a solid online cleaning chemical product from SolidTek Limited. 

Looms continued: “We chose to use SolidTek’s solid online cleaning chemical because it is easier for us to introduce the quantities required. Also, solid chemicals dissolve at a steady, constant rate, as opposed to liquid chemicals which are introduced in one go. This ensured even distribution of the cleaning chemical throughout the system and meant that suspended solids were not mobilised too quickly, preventing potential blockages.” 

The remainder of Anker Elemental’s remediation programme includes bi-monthly visits to the site, where water quality samples are taken for analysis and the filter bags inside DosaFil-Duo are changed (a process which takes less than five minutes). 

DosaFil-Duo is the only water conditioning device on the market with smart monitoring technology out of the box that automatically notifies users when filter bags require changing (with communication options for BMS built-in as standard). 

This feature was particularly attractive to the Head of Maintenance at the Police authority, as well as the principal mechanical contractor on the job. Looms said: “The filtration alarm provides reassurance to the customer that filter bags are changed as necessary, ensuring active and efficient management of the remediation process. Without such an alarm, the client would have to rely on the filter bags being checked regularly. This approach leaves room for error, or at best wastes labour and resources.” 

Work started over the summer period, when large parts of the system were offline. For the parts of the system that were online, DosaFil-Duo delivered excellent results: “We worked down from a 50-micron filter to a 10-micron filter, which shows just how much suspended solids the DosaFil-Duo picked up,” explained Looms. “We’ve only had to switch back up to a 25-micron filter since the offline sections of the system were placed online, as this mixed dirty water back in to the cleaner water. However, we’re confident that the system will be clean soon given DosaFil-Duo’s efficient performance.”

Results from the water quality samples have also been positive. “We test each sample for variables such as iron content, turbidity, conductivity and so on, and have seen vast improvements in water quality. In addition, we have documented progress for the client, who is pleased to receive visual and data evidence of the cleaning and protection programme.” 

Anker Elemental has also since introduced a liquid chemical corrosion inhibitor into the system via the DosaFil-Duo device. “It is really important for us that we can use solid and liquid chemicals in the system as it gives us more control over the water treatment process, and DosaFil-Duo is the only device on the market which can do this,” said Looms. 

The Police authority has been so impressed with DosaFil-Duo that a second device has now been installed in another building, this time on an existing medium pressure hot water system. DosaFil-Duo’s standard operating pressure and temperature ranges are unmatched in the market, enabling DosaFil-Duo to be used in a far wider range of systems (such as medium pressure hot water systems) than most other similar devices. 

Furthermore, the principal mechanical contractor recommended DosaFil-Duo to the council, where two further devices have since been installed. 

Steve Crick, Managing Director of DosaFil, concluded: “The contractor and end-user have recognised the value of DosaFil-Duo as a means of cleaning, protecting and maintaining closed circuit systems in a cost-efficient and convenient manner. As a relatively new British manufacturer in the highly competitive HVAC industry, we are delighted that DosaFil has so quickly established itself as a highly-regarded and exceptionally effective conditioning device.”

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