Why Is Replacing Sauna Stones Important?
The condition of sauna stones has a direct impact on the lifespan of the sauna heater, which is why replacing the stones is one of the most important heater maintenance tasks. If sauna stones are not replaced regularly, they will begin to crumble and can ultimately damage the heating elements. Crumbling, worn‑out stones also affect the electricity consumption of an electric heater as heating time increases and overall energy use rises. A well‑maintained sauna heater is safe to use, functions correctly, and keeps electricity consumption at an optimal level.
Regularly replacing sauna stones also improves overall sauna comfort, as one key ingredient of perfect steam lies in the stones themselves. For example, in the Rakka heater, the heater’s structure combined with its massive stone capacity vaporizes water in a way that produces rich, long‑lasting, and humid steam, similar to that of a wood‑burning heater. Both the heater and the stones play an important role in the quality of the sauna experience.
Over time, various odors and impurities may also develop in the sauna and become absorbed into the stones. Replacing the stones helps improve indoor air quality and remove unwanted smells. New stones provide a cleaner and more hygienic sauna experience, while old stones can accumulate dirt and bacteria over time. Changing them regularly helps keep the sauna fresh and clean.
It is important to keep the replacement interval in mind and monitor the condition of the stones. If the stones appear to be crumbling, it is time to replace them. One common sign of deterioration is a recently sunken stone surface inside the heater. In some cases, damaged heating elements are the first indication that the stones should have been replaced earlier. As a general rule, sauna stones should be replaced every 100 sauna sessions. If you sauna twice a week, this means replacing the stones approximately once a year. The user interface of Mondex WiFi sauna heaters also provides reminders when the stone replacement interval is approaching.
Stack sauna stones carefully
Correct stone stacking is essential to prevent damage to the heating elements.
Instructions for stacking sauna stones:
- Removing old stones: Begin by removing all old stones. Clean out any debris or stone fragments that may have accumulated inside the heater.
- Rinsing new stones: Rinse new sauna stones with water before placing them into the heater. This ensures clean, fresh steam and prevents unnecessary dirt from spreading in the sauna during the first sessions.
- Stacking the stones: Stack the stones so that those placed between the heating elements are arranged more loosely, while stones on the outer sides are stacked more tightly. This allows proper air circulation around the elements. Stones must not wedge against or press on the heating elements, as this may cause them to bend or break. Wearing gloves is recommended when handling sauna stones.
Recycling sauna stones
Recycling sauna stones is an environmentally friendly way to dispose of them. Most sauna stones consist of natural stone material, which means they can often be reused in your own garden, for example around plants or flower beds.
A small number of stones can be disposed of with mixed waste, but larger quantities should be taken to a local recycling facility. Recycling practices may vary by location, so always check the guidelines provided by your local waste management authority.
Sauna stones for the Mondex sauna heater
Mondexin erikoisuusMondex's speciality, the Rakka heater, appears externally to be made entirely of stone and requires special perforated stones as its outer layer. These stones have a longer replacement interval than regular sauna stones. However, the inner stones beneath the perforated layer must still be replaced according to the standard recommendation of approximately every 100 heating sessions. When replacing the inner stones, the positions of the perforated stones can be rotated so that stones previously located lower are moved upward and vice versa. The upper stones are exposed to higher temperatures during operation and therefore wear out faster. Perforated stones should typically be replaced after three to five replacement cycles of the inner stones.
The required stone quantities for different Mondex sauna heater models can be found in the technical specifications. New sauna stones are available from our retailers across Finland and online.