High-tech and reliable


The benefits at a glance

  • High efficiency with advanced combustion technology, triple-pass heat exchanger and modulating output control (turndown ratio 4:1).
  • Maximum heat transfer with triple-pass heat exchanger design.
  • High efficiency and ultra-low emissions with precisely controlled primary and secondary air.
  • Automatic ignition device limits idling and saves fuel.
  • Low maintenance with fully-automatic deashing, optional pneumatic cleaning system and flue gas deduster.
  • Advanced safety equipment ensures safe and reliable operation.
  • Custom design of your system by our team of experts.

Industry-leading design

With its patented rotary combustion chamber design, the Vitoflex 300-RF boiler features the industry's most advanced combustion technology. A feed auger continuously moves the wood fuel onto a moving grate, where gasification of the fuel (under precisely controlled primary air) takes place. The combustible gases (syngas) then rise into the rotary combustion chamber, where, through spin impulses of the rotation blower, the gases blend with precisely controlled secondary air, resulting in a complete combustion.

Containerized package

The Vitoflex 300-RF is available as a fully containerized package for applications where housing for the boiler is not available or onsite construction costs must be kept to a minimum. This pre-packaged solution includes the boiler pre-installed in a specialized shipping container and all peripheral equipment. Customized containerized packages are available to suit your individual needs.


Clean-burning and efficient

Equivalent in quality to modern gas combustion, the advanced combustion process of the Vitoflex 300-RF also keeps emission levels of CO (<10 ppm), NOx (<75 ppm) and dust particles (<0.06 lb/ MMBtu) to a minimum.

Plus, unlike oil or gas, wood is a CO2-neutral, renewable form of energy. Used with our digital, modulating-output control, the Vitoflex 300-RF boiler achieves an efficiency of 85%.

Where can I buy a Vitoflex?

To get a quote for a new Pyrot wood heating system including installation, please contact the biomass team at our head office:

Viessmann Manufacturing Company Inc.
45 Access Road
Warwick, RI 02886

Tel.    401-732-0667
Tel.    800-288-0667 (Toll-free)
Fax    401-732-0590

Email  info@viessmann-us.com

Product details


512 to 1843 MBH - 150 to 540 kW
Combustion type
Rotary combustion
Maximum water temperature
250 °F / 120 °C
Pellets, woodchips with max. water content of 35%
Application range
For apartment buildings, commercial applications and district heating, new buildings and retrofits.
Additional features
Fully automatic ash removal.
Cutaway view


A perfect match – System technology

"The whole is greater than the sum of its parts." According to this philosophy, Viessmann does not just make individual heating equipment components that meet the high Viessmann standards for quality, reliability and effectiveness. Rather, all products are part of a matching concept, where all components complement one another. Only the perfect interaction of system integrated components draws out the maximum potential of our innovative leading technology.

Viessmann system technology includes everything you need for a reliable and economical heating system. The Vitotronic control unit with remote control, the powerful Vitocell DHW tanks for best DHW convenience, to high-quality solar thermal systems for cost-saving heating.

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