Instructional video: How to stack sauna stones into a pillar-model electric heater
Good to know about heater stones and heater maintenance
Due to the strong thermal cycling, the heater stones become weathered and crumble during use.
Re-load the stones at least once a year, more often in heavy use. At the same time, remove any stone debris that has accumulated in the stone space and replace broken stones. This will ensure that the stove retains its fire-extinguishing properties and that there is no risk of overheating.