Case Study from HydroFLOW France
Hospital hot water scale on very hard Colmar water
Hospital hot water scale is a constant pressure at the 206-bed MGEN Trois-Épis rehabilitation centre in Alsace, where domestic hot water is produced from very hard Colmar water at approximately 330 ppm. The site relied on six ageing salt softeners whose resins needed replacing and whose regeneration consumed significant salt and water. It also saw a few Legionella alerts on its hot water network each year. Twelve HydroFLOW® units replaced the softeners across 2,550 kW of hot water production, installed in a single day without interrupting water service. Five years on, no limescale-related maintenance has been needed, Dalkia has recorded no callouts for scale-blocked pipes, and a dismantled plate exchanger showed no trace of limescale.
The Challenge
- Hospital hot water scale control depended on six ageing salt softeners
- Very hard Colmar water at approximately 330 ppm fed the domestic hot water system
- Softener regeneration consumed significant salt and water
- Ageing softener resins were due for replacement
- A few Legionella alerts occurred on the hot water network each year
The Solution
- Units installed: twelve HydroFLOW® units
- Installation point: main substation, four exchangers, a villa boiler and three villa tanks
- Water: very hard Colmar supply, approximately 330 ppm
- Previous treatment: six salt softeners
- Monitoring period: five years of maintenance contractor records
All twelve units were fitted in one day without interrupting water service, covering the main substation, the 300 kW Roseraie exchanger, the 200 kW Leisure and Balneo exchangers, a villa boiler and the tanks in three villas. With the softeners removed, hospital hot water scale control now comes from the signal alone, so there is no salt, no regeneration water and no resin to replace.
