How one large hotel solved its Legionella problem

Combatting Legionella and other bacteria in hotel water systems has never been more challenging.

Project details

Client A leading UK Hotel Group
Location Kent, South East England
System ChloriDOS iOX® Modular
Model iOX 10

With many venues being empty for some two years due to Covid and the slow return of guests post Covid.

Using our unique ChloriDOS® iOX® patented technology, has helped one hotel improve their water quality and get it back into safe compliant levels.

With over 130 guest bedrooms, bars and restaurant plus a gym and pool, this large and very busy hotel consumes a lot of water. Unfortunately, testing revealed the presence of high levels of Legionella in its hot water supply. Despite following best practice by cleaning water tanks, checking for low flow areas and repeatedly flushing the system, the high readings persisted.

The hotel decided to install a secondary disinfection system to treat the cold water feed to the hot water circuit. It chose WRAS approved ChloriDOS® iOX® 10,  Gaffey’s chlorine dioxide (ClO2) dosing system, which can treat up to 20m3 of water per hour. Larger ChloriDOS® iOX® models can treat up to 100m3 of water every hour.

ChloriDOS® was connected within a day and set to give 0.5ppm of ClO2 in the cold water feed tank – calculated by Gaffey as the optimum level to disinfect the entire hot water circuit. Initial tests at the hot water outlet furthest from the input tank confirmed there was still residual ClO2 in the water, proving that the initial dosing was accurate and sufficient biocide remained in the water to provide ongoing protection.

Repeated testing showed consistent ClO2 levels being sustained demonstrating that ChloriDOS® iOX®’s calibrated-for-life dosing technology was continuing to produce exactly the right amount of biocide to keep the hotel’s hot water system safe.

Not only do ChloriDOS® iOX® systems need minimal maintenance, they use unique, accurate blending technology that significantly reduces the chemicals required for effective chlorination. This combination of efficient operation and dosing will realise a recurrent annual cost saving to the hotel’s owners.

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