Hotels provide case study of physical water conditioning and ion exchange

The relative pros and cons of ion-exchange water softeners compared with physical water conditioners are highlighted by installation at Two Radisson SAS Hotels, one in London’s Portman Square and the other at Stansted Airport. The Portman has 272 bedrooms and uses 40 t of salt a year at a cost of £6800. Servicing the softener adds a further £1800 to bring the total annual cost to £8600. For cleaning and sterilising shower heads, there is a rolling 3-month programme of removal, soaking in sulphamic acid and replacement. The hotel at Stansted Airport opened in 2004 and has 500 rooms on five floors. It uses 48 000 m3 of water a year with a hardness of 315 ppm calcium-carbonate equivalent. It has two Water-King WK4 units from Lifescience Products on the 10 cm boosted cold-water service and a WK3 on each of the 5 cm returns from the Hoval plate and frame heat exchangers. Their total installed cost was £5100, and their total annual running costs are just £40. The Hoval heat exchangers are opened every year in November for inspection and descaling. Simon Pearson, chief engineer for the two hotels, described them as ‘spotless — the Water-Kings keep them completely scale free’. The shower heads of the hotel at Stansted Airport are maintained in the same way as those at Portman Square. However, some shower heads show slight marking from scale encrustation towards the end of the -3-month period before they are cleaned. Simon Pearson describes the problem as ‘aesthetic’. The showers still work normally. The scaling is not heavy, but some is visible so the condition of the shower heads cannot be described as perfect. Given one estimate of £45 000 for installing conventional water softeners at Stansted and projected sale and maintenance costs of £15 600 a year, Simon Pearson is content to live with this minor aesthetic problem. He is also very impressed by the cleanliness of the heat exchangers and cognisant of the reduced environmental impact of the Water-King units. Jonny Seccombe, managing director of Lifescience products comments, ‘Simon’s experience at the Radisson SAS bears out our advice to hotel owners. For a 5-star hotel, you really could do with an ion-exchange softener. A 4-star hotel has the choice of using physical water conditioning. 3-star or less, a Water-King is the most sensible option.’

Related links:

• www.hoval.co.uk/

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