Sauna stones Harvia AC3020 Ø 10–15 cm, 20 kg pack

Harvia AC3020 sauna stones Ø 10–15 cm, packed in a 20 kg bag, are volcanic rocks intended for use in both electric and wood-fired sauna heaters. These stones are sized to fit typical heater stone chambers and are chosen for their heat retention and ability to create even steam when water is poured over them. Designed to replace worn or cracked stones, the set helps maintain consistent temperature distribution and humidification in the sauna.

Advantages

The stones are made from dense volcanic material that retains heat effectively and resists frequent thermal cycles. Their Ø 10–15 cm size provides a balance between surface area for steam formation and mass for stable heat storage. Supplied as a 20 kg pack, the quantity is suitable for topping up or refilling most domestic and small commercial sauna heaters. The stones are irregularly shaped to allow airflow between pieces, improving circulation and even heating.

Suitable for

• Electric sauna heaters that accept Ø 10–15 cm stones
• Wood-fired sauna stoves requiring durable heat-retaining stones
• Replacement of broken or heavily weathered sauna stones
• Refilling stone chambers to restore even heat distribution and steam production

Key specifications

• Stone material: volcanic rock (heat-retaining natural stone)
• Stone diameter: approximately 10–15 cm
• Pack weight: 20 kg
• Shape: irregular pieces promoting airflow and even heating
• Intended use: suitable for electric and wood-fired sauna heaters

How to use

Before adding new stones, ensure the heater is cool and disconnected from power or fully extinguished if wood-fired. Remove any crumbled or damaged stones and clean the stone chamber of ash or debris. Place the Ø 10–15 cm stones into the chamber so they form a stable, well-ventilated stack that allows air to circulate between pieces while covering heating elements as recommended by the heater manufacturer. After refilling, heat the sauna gradually for the first use to allow the stones to adapt to thermal cycling.

Usage recommendations

Use the stones in accordance with the sauna heater manufacturer’s instructions regarding maximum stone pile height and placement. Replace stones in sections if some pieces are still intact, and inspect periodically for cracking or crumbling. For safe steam production, pour water sparingly and at safe distances from heating elements and control units. Store unused stones in a dry place to avoid contamination with dust or debris.