All-in-one boiler protection
Pump, valve, and thermometer in one station
Combines return-temperature protection, circulation, and temperature monitoring in one insulated assembly.
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UNI Series — Best for Most Wood Boiler Projects
Heating Capacity: Up to 8,000 ft²
The largest model in the standard UNI size tier, before stepping up into the UNI Industrial range.
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Installed in real homes and workshops
A proper installation is the foundation for reliable performance, greater efficiency, and long-term comfort with your UNI 15 boiler.
UNI 15 Boiler Installation
See how an installer sets up the UNI 15 boiler step by step for reliable, long-lasting performance.
High-efficiency wood boiler designed for large commercial and high-demand applications, featuring gasification technology, extended burn time, and multi-fuel flexibility for powerful and reliable heating performance.
| Heat area | Up to 8,000 ft² |
|---|---|
| Water volume | 48 gal |
| Connection | 2 in |
| Chimney | 8 in |
| Firebox size | 81 gal |
| Log length | 30 in |
| Width | 39½ in |
| Depth | 50 in |
| Height | 69 in |
| Weight | 1,490 lb |
Complete the system
All-in-one boiler protection
Combines return-temperature protection, circulation, and temperature monitoring in one insulated assembly.
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Water heater tank
The combined buffer and indirect tank stores boiler heat and supplies household hot water — no separate water heater needed.
View detailsBoiler protection
A thermostatic valve keeps return water above 130°F to reduce condensation and corrosion inside the boiler.
View detailsUNI remote control
Connects compatible TIS controllers to Brager Connect for remote monitoring, alarms, and adjustments.
View detailsAnswers
UNI is a wood gasification boiler built for homes, workshops, and estate heating. It burns firewood in two combustion stages and transfers the heat into a hydronic system for space heating and domestic hot water.
UNI 15 covers up to 2,500 ft², UNI 40 up to 4,000 ft², UNI 60 up to 5,000 ft², and UNI 95 up to 8,000 ft². For commercial or industrial-scale loads, see the UNI Industrial sizes (150–1000). Square-footage ranges are approximate — final sizing depends on heat loss, insulation, climate, and how the boiler will be used.
UNI and TITAN Lambda are both the stronger fit for wood gasification heating. TITAN Lambda adds automatic ignition and lambda-sensor combustion control for up to 95% efficiency; UNI's smart controller delivers 86%+ efficiency with a simpler design. PRO is the non-gasification, off-grid option that needs no electricity at all.
Yes — UNI pairs with a domestic hot water tank such as the APOLLO DHW80 to provide hot water alongside space heating from the same boiler.
Many wood gasification boiler systems benefit from a buffer tank, because a full burn can produce more heat than the building needs at that moment. Thermal storage can capture that heat, reduce cycling, and improve comfort when the system is designed correctly.
Maintenance includes burning dry wood, removing ash, cleaning heat exchanger surfaces, inspecting the chimney and flue, checking door gaskets, and servicing pumps, controls, valves, the expansion tank, and water quality.
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