Free Flow

The Free Flow is a highly effective, reliable, safe and long-lasting heating device. The outward functional form of the Free Flow has remained unchanged for forty years now because it simply cannot be improved upon as a design for a pure hot air stove. Having originally been conceived as a stand-alone wood-fired heating device – and often used as the only heat source – one of the key qualities of the Free Flow hot air stove has always been the fast and even heating of rooms. Lined with high-quality vermiculite, the Free Flow 2017 (FF17) meets all emissions requirements currently in force in Germany and Europe.

The striking and logical design of the Free Flow is so unique that it makes a positive statement in any sur- roundings. It is equally at home in the countryside, in town, or in the workshop. As such, the Free Flow also stands out for the way its appearance and operation can be adjusted. The combination of side-covers or stor- age ceramic, bases and handles allows you to design your Free Flow to best suit you and the space where you intend to install it. Different nominal heat output ratings (6.8 to 14.2 kW) allow it to be used not only in small but also in very large space.

The Free Flow is a hot air stove in its purest form. Air from the room is quickly heated in the convection pipes without direct contact with the fire and rises up (thermal convection effect). Cooler air from the room flows up into the pipe and is also heated. The undetectable flow of air created in this way spreads the heat immedi- ately, quickly and evenly into the spaces to be heated. Due to these exceptional heating qualities, the Free Flow is often used in spaces with complex layouts, or in sporadically heated areas such as function rooms or conservatories.

New: from the middle of March 2017, the FreeFlow FF17 is also available as a “Basic” version with all types. In this variant, the oven is supplied without thermal safety cover. When operated without cover, a distance to combustible materials of 70 cm must be observed only.

The Highlights

Main features and design
  • The epitome of a high-performance hot air/convection stove
  • Nominal heat outputs: 6.8 kW (Type 00), 10 kW (Type 01) and 14.2 kW (Type 02)
  • Very high efficiency factor of up to 81 per
  • Choice of various heat-protective covers mode of steel, stainless steel and glass
  • Hand-made Bavarian heat-storing ceramics in many colours available for type 00 and 01
  • Handle versions in wood or steel (chromed or brass-plated)
  • Different pedestals allow various designs and height settings
  • Height adjusters in the pedestals (with the exception of Carré) allow the stove to be levelled on uneven floors


Function and quality – Made in Germany
  • Extremely robust combustion chamber made of curved steel pipes
  • Fire box lined with high-quality vermiculite
  • Effective integrated window washing system
  • Intuitive control of the fire using a precisely coordinated inflow of air
  • Warranty extension (total 5 years) to the stove body on registering the product
  • Comprehensive service offering by the Bullerjan specialist dealers or Bullerjan customer service


ModellFree Flow FF17
Type 00
Free Flow FF17
Type 01
Free Flow FF17
Type 02
Performance6,8 kW10,0 kW14,2 kW
Depth62,4 cm72,1 cm88,2 cm
Width52,3 cm59,9 cm64,0 cm
Width for model Basic -
without cover
44,3 cm52,0 cm57,0 cm
Width with heat accumulators ceramic61,0 cm66,0 cmNot available for this type
Height63,8 cm66,9 cm80,0 cm
Weight for model Basic - without cover 83,2 kg 107 kg 140 kg
Weight incl. heat safety covers 90 kg 115 kg 150 kg
Weight with equipment ceramic 187 kgNot available for this type
Depth of combustion chamber37,5 cm47,5 cm57,5 cm
Exhaust gas nozzleØ 12 cmØ 12 cmØ 15 cm
Air supply nozzleØ 10 cmØ 10 cmØ 10 cm
Height centre exhaust gas nozzleca. 47,0ca. 51,0 cmca. 48,0 cm
Height centre air supply nozzleca 19,2 cmca. 34,2 cmca. cm
Exhaus gas mass flow rate (nominal heat output)9,7 g/s9,8 g/s11,0 g/s
Delivery pressure12 Pa12 Pa 12 Pa
Mean exhaust gas temperature225 °C290 °C346 °C
CO content (13 % O2 )0,10 Vol.-%0,08 Vol.-%0,10 Vo.-%
CO content (13 % O2 )
1250 mg/m³1000 mg/m³1250,0 mg/m³
NOx (13 % O2 )126 mg/m³20 mg/m³ 95 mg/m³
Dust (13 % O2 )28 mg/m³20 mg/m³22 mg/m³
Efficiency 81 %80 %80 %
Distances to combustible