It is recommended to replace the filter sand every 6-8 years. The screens inside the filter also need to be replaced often. Large filters are easier to work with. It is more difficult with smaller ones, which are not always easily accessible and the filters may have been poorly installed during construction.

The price of the filter sand replacement service depends on the size of the filters, their accessibility, the mass of the sand, and their location in the house. The replacement process itself is time-consuming: the old sand must be removed, the internal body must be washed, new screens and new sand must be installed (coarse sand at the bottom of the filter and finer sand on top).