HUUM Hive Flow Wood-Fired Sauna Heater

The HUUM Hive Flow Wood-Fired Sauna Heater is engineered to deliver high thermal efficiency with a significantly reduced environmental footprint. Its advanced combustion system is designed so that approximately 75% of the heat generated by firewood is transferred directly into the sauna, rather than being lost through the chimney. In real use, this efficiency allows for four sauna sessions using the same amount of wood that would normally provide only three.

At the heart of the Hive Flow is HUUM’s patent-pending airflow and combustion technology, which dramatically lowers emissions. Carbon monoxide output is limited to 346 mg/m³, compared to more than 1,000 mg/m³ commonly seen in comparable wood-burning stoves. Particulate emissions are reduced to just 25 mg/m³, placing the Hive Flow among the cleanest wood-fired sauna heaters available.

This efficient heat circulation also enables exceptionally short safety distances. The Hive Flow requires only 150 mm of clearance from combustible materials, compared to the typical 200–500 mm. Even heat distribution across the stove body prevents localized hot spots, making it suitable for more compact or precisely planned sauna installations.

Constructed for durability and consistent performance, the stove features a 5 mm thick steel top and 3 mm thick side panels. This robust build promotes even heat release and long service life. The standard Hive Flow weighs 67 kg (73 kg for the LS version) and supports up to 150 kg of sauna stones, with the option to add 35–40 kg more using the external stone cage.

The large stone mass stores heat effectively, allowing for long, gentle steam sessions that continue for over 30 minutes after the fire has burned out. This creates a soft, balanced sauna environment rather than sharp, aggressive heat.

A large glass furnace door adds both function and atmosphere, allowing you to enjoy the movement of the flames and creating a warm, fireplace-like ambiance within the sauna space.

The Hive Flow meets and exceeds strict environmental requirements, complying with Germany’s BImSchV Stufe 2 standard and European Commission Regulation 2025/1185 for solid fuel local space heaters. These certifications confirm its position as a forward-looking, environmentally responsible choice for wood-fired sauna heating.

The HIVE Flow LS (loading side) model allows the stove to be fired from an adjacent room, improving cleanliness and convenience within the sauna itself.

Additional variants are available, including the HIVE Flow Mini and Mini LS, weighing 54 kg and 59 kg respectively and holding 105 kg of stones. With the optional stone cage, these models can accommodate up to 40 kg of additional stones.

Stove Details

• Power Output: 9.8 kW

• Recommended Sauna Room Size (Minimum): 282 ft³ (8 m³)

• Recommended Sauna Room Size (Maximum): 635 ft³ (18 m³)

• Stone Capacity: approx. 330 lb (150 kg)

• Unit Weight: 148 lb (67 kg)

• Heater Dimensions:

  • Height: 34.8? (884 mm)

  • Width: 20.7? (526 mm)

  • Depth: 23.1? (586 mm)

• Maximum Firewood Length: 11.8? (300 mm)

• Flue Diameter: 4.5? (114 mm)