Versatile Heating Solution for Smaller Installations
The KWB Multifire2 is designed to serve small to medium heating demands with automatic operation and high energy efficiency. It combines flexibility with advanced combustion technology, so you get consistent performance whether you’re heating a multi‑unit building, workshop, commercial space, farm facility or a small heat network.
Ideal for a Range of Settings
The Multifire2 is perfect wherever reliable biomass heating is needed, including:
- Residential buildings and multi‑family homes
- Small‑to‑mid‑sized commercial properties
- Agricultural facilities
- Light‑industrial and workshop spaces
- Community buildings and small district heat systems
Its revolutionary crawler burner technology ensures reliable performance even in continuous high-load applications.
Fuel Flexibility
One of the key strengths of the KWB Multifire2 biomass boiler is its ability to operate with different biomass fuels.
Supported fuels:
- Wood chips (up to 40% water content)
- Shredded wood
- Wood pellets
The Multifire2 accepts both wood chips and pellets, and its automatic combustion control ensures optimal performance even with varying fuel qualities. This gives you the freedom to choose fuel based on availability and cost.
Advanced Combustion Technology
The crawler burner is the heart of the KWB MultiFire2’s combustion process. Fuel is slowly carried along the moving grate, allowing it to dry, gasify, and burn in carefully controlled stages. This continuous movement prevents buildup, reduces ash and slag, and ensures consistent, efficient heat output. Even with varying fuel types and qualities, the system maintains low emissions and high performance. Unlike some competing technologies, the crawler burner never needs to power down for cleaning, providing uninterrupted operation and maximum reliability.
The heat recovery unit features a vertical three-pass fire-tube heat exchanger with an extensive heating surface, allowing the Multifire2 to achieve nominal output even with fuels containing up to 32–35% moisture. An automated cleaning system employs spring-based mechanisms inside the tubes to remove fly ash as it accumulates. The ingenious design induces a spinning motion of the flue gases within the tubes, enhancing heat transfer and maximizing efficiency. Dislodged ash falls to the bottom of the unit, where an auger beneath the heat exchanger transports it to a dedicated ash container, ensuring convenient and hassle-free disposal.
Intelligent Control & Monitoring
The Multifire2 KWB Comfort 4 combines intuitive controls with advanced functionality to ensure optimal performance and ease of use.
Operation is simple with a scroll wheel and two buttons, while the dual “turn & press” function allows for easy navigation through menus. The 4.3” touch display provides clear system feedback and settings at a glance.
Remote monitoring and control are available through Comfort Online (basic version included free of charge). The integrated KWB algorithm ensures efficient, modulating boiler operation and precise buffer management with support for up to five buffer sensors. For larger installations, the system supports cascade control and boiler sequencing, enabling multiple boilers to work together seamlessly for reliable, high-efficiency heating.
Smart Monitoring and Remote Control
With KWB Comfort4 control connected to Comfort Online, operators can monitor and control the heating system remotely from a smartphone, tablet, or computer.
Features include:
- Real-time system monitoring
- Status alerts
- Remote access for technicians and service providers
- ModBus connectivity for smooth integration on larger control systems
This digital control platform ensures greater reliability, easier troubleshooting, and improved system management.
Designed for Easy Transport and Setup
The MultiFire2 is designed with a modular construction, allowing for quick, flexible, and hassle-free installation. Its components can be transported and assembled on-site with minimal effort, making it ideal for new buildings, retrofits, or locations with limited access. The modular layout also simplifies maintenance, as individual sections can be removed or serviced without dismantling the entire system, reducing downtime and installation costs.
Benefits include:
- Easier transport into boiler rooms
- Simplified installation in existing buildings
- Reduced maintenance effort
- Long-term durability thanks to high-quality components
Various silo solutions are available depending on the fuel type, delivery method, and the required operating time of the boiler between silo refills.
Scalable Output
Currently, the Multifire2 boiler has CSA certification for an output of 120kW (409,000 BTU/hr) and the certification process is underway for the following outputs: 60kW (205,000 BTU/hr), 80kW (273,000 BTU/hr), 100kW (341,000 BTU/hr). For greater outputs, multiple KWB Multifire2 boilers can be combined.
For projects with higher heat demand, multiple KWB Multifire2 boilers can be installed in a cascade configuration. This modular approach allows large facilities or district heating networks to match heating capacity precisely to their needs while maintaining operational flexibility. Boilers can be staged to operate based on real-time demand, improving efficiency, system reliability, and maintenance scheduling.
Reliable, Efficient, and Connected Heating
The KWB Multifire2 combines advanced combustion technology, modular design, and intelligent modulating automation to deliver efficient, reliable, and environmentally friendly biomass heating. From the durable crawler burner to the high-performance heat recovery unit, every component is engineered for maximum efficiency and minimal maintenance. Its flexibility with wood chips and pellets, modular layout for easy installation, and Comfort Online connection for remote monitoring and control make it an ideal solution for residential and commercial buildings, agricultural facilities, and small district heating systems.
With the KWB Multifire2 biomass boiler, sustainable, high-efficiency heating has never been more accessible, dependable, or convenient.
Key Benefits
- High Efficiency Heating: Automatically optimized combustion.
- Flexible Fuel Compatibility: Works with wood chips and pellets.
- Automated Operation: Minimal maintenance and automatic fuel handling.
- Low Emissions & Eco‑Friendly: Clean combustion and reduced environmental impact.
- Made in Austria Quality: Durable design, engineered for reliability.