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Best limescale protection for drinking water installations.
In BWT limescale protection systems - such as AQA nano or AQA total Energy - the unique nanocrystal technology is used. Tiny nanocrystals are formed that stabilise the limescale dissolved in the water. This means that the lime remains in the water, but cannot be deposited. And all the other valuable minerals are also retained in the water.

Technical details

Product number: 023301
Area of application according to DIN 1988-200 Dwelling units | Persons: up to 3 persons
Assembly: Wall mounting
Dimensions in mm (w x h x d): 300 x 710 x 290 mm
Limescale protection: up to max. 20 °dH
Standby power: 1.8 Wh
Water treatment capacity: 25 l/min
Water treatment capacity: approx. 110 m³


Every waterworks knows the hardness levels of the drinking water it supplies and will answer enquiries about the water hardness at your place of residence. In many cases, the respective water hardnesses are also listed on the website of the waterworks.
Alternatively, you are welcome to use our online water hardness search or request a water hardness test strip from us free of charge.
A question that we have to enter the realm of chemistry to answer. Lime is a substance that occurs in nature - in its most compact form as marble. The chemical name for it is CaCO3, which means calcium carbonate. You can find out more about lime in the "Worth knowing" section of our magazine;
Depending on whether you want to get rid of limescale in the long term or at least reduce its negative effects, there are two different methods.
A water softener is the right solution if the limescale content in the water is to be permanently reduced.
Limescale protection devices form tiny crystals of calcium carbonate from some of the limescale dissolved in the water, which in turn bind the remaining limescale to themselves. This prevents the limescale from settling in the pipes or boilers. The ideal solution for everyone who wants to leave valuable minerals in the drinking water and still enjoy safe limescale protection.

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