CalcFree

CalcFree has been developed by Guldager and is a water treatment plant with carbon oxide acid addition to prevent stones and lime in hot-water installations.
When water is heated, lime is precipitated as stones on the installation surfaces. Stone precipitation is directly dependent on the hardness of the raw water and the heating temperature. In Denmark, where we are normally having a lot of trouble with hard water, installations with heated water, in particular, have always been especially exposed to stone precipitation.
A mixer must be mounted on the inlet to ensure a good absorption of the carbonic acid. To achieve an effective functioning of the mixer the flow must be around 1.4 m/s. Heat exchangers and heating elements are kept free of stones using CalcFree, however, as soon as the water in the piping system gets colder causing a natural fall in the circulation system, it may become corrosive. We therefore recommend that you never install a plant without having considered the construction of the installation as well as the choice of materials, and in most cases plants should only be installed if a catholysis unit is available for corrosion prevention.

Generally, CalcFree should not be used in installations with copper pipes, except for plants with heating elements of copper and plants where copper is used as the last section for tapping points. The reasons adduced for installing CalcFree should always be that there are problems with precipitation of lime. When CalcFree has been installed, after a certain period (e.g. ½ to 1 year) it should be considered whether the carbonic acid addition is appropriate.