Sauna stones don’t last forever. Contact with water and temperature fluctuations have an impact, and over time they eventually start crumbling. Therefore it is natural that every now and then they should be replaced with new stones.
Frequency of inspecting the condition of sauna stones and replacing them depends on:
frequency of using the sauna, and
the quality of sauna stones.
How frequently should sauna stones be exchanged?
Check the condition of sauna stones once a year or after 300 hours of heating.
If you heat your sauna three times a week on average, you should replace the sauna stones once a year.
If you use your sauna less frequently, you should exchange the sauna stones once every couple of years.
You should check the condition of the sauna stones when heating the sauna takes more time than usual or when the sauna heater does not warm up properly. This may be caused by small stone pieces that block air movement between the sauna stones.
How to check the condition of the sauna stones?
In order to inspect the condition of the stones, remove all the stones from the heater.
Replace all the sauna stones that are eroded or have become remarkably lighter.
Clean sauna stones that are dusty or covered with residues of iron-rich water.
The most convenient solution is to replace all the sauna stones at the same time.