Defro Firewood Plus 15 kW natural draft boiler

2025-04-16T12:24:18+02:00

Vendor: Defro
Type: Solid fuel boiler
Price: 2519.00

The Defro Firewood Plus 15 kW This is a modern natural draft wood-burning stove with electronic primary air control and an integrated safety heat exchanger. With an efficiency of 92.3% and an energy efficiency rating of A+, it is ideally suited for new or existing single-family homes.

Highlights/Advantages

⭐ 92.3% efficiency – efficient heat utilization and reduced fuel costs
⭐ Energy efficiency class A+ – future-proof wood heating
⭐ Integrated safety heat exchanger – suitable for closed heating systems
⭐ Electronic primary air control – convenient combustion control
⭐ Multiple connections possible at the chimney – flexible integration into existing buildings

Detailed description

Area of ​​application & Target audience

The Defro Firewood Plus 15 kW is a natural draft boiler for burning logs (hardwood, residual moisture 12–20%). With its nominal output of 15 kW, it is particularly suitable for single-family homes with medium heating requirements or modernized existing buildings.

The secondary air can be adjusted on both sides, allowing for placement close to a wall and flexible mounting conditions.

Everyday benefits

The electronic control system automatically regulates the primary air supply and can also control the boiler circulation pump and an optional induced draft fan.

Large loading doors ensure convenient loading of logs up to 290 mm in length. An integrated sight glass allows visual monitoring of the gasifier flame during operation.

Technology & equipment

The boiler body is made of high-quality steel. The factory-installed safety heat exchanger allows for installation in closed heating systems.

The required delivery pressure is 0.20 mbar. The boiler is suitable for multiple connections to a common chimney.

Efficiency & Environment

With a standard efficiency of 92.3%, the Firewood Plus 15 kW achieves energy efficiency class A+.

The recommended minimum buffer storage capacity is 800 liters to ensure efficient and low-emission operation.

compatibility & System integration

The exhaust connection has a diameter of 159 mm.

The flow and return lines are made with 1½" (IG) threads.

The electronic control system is powered by a 230 V/50 Hz supply.

Suitable accessories such as buffer tanks, thermal relief valves, safety groups or boiler circuit sets can be found in the product range at gemashop.de.

Technical data

feature | Value
Manufacturer | DEFRO
Model | Firewood Plus 15
Product type | Natural draft kettle
Rated power | 15 kW
fuel | Firewood (hardwood 12–20%)
efficiency | 92.3%
Energy efficiency class | A+
boiler weight | 348 kg
Exhaust gas temperature | 142 °C
Exhaust gas mass flow | 12.5 g/s
CO₂ content | 12.6%
Required delivery pressure | 0.20 mbar
Exhaust connection | Ø 159 mm
Flow/Return | 1½" internal thread
Flow temperature min./max. | 75/90 °C
Minimum return temperature | 65 °C
Minimum buffer capacity | 800 l
power supply | 230 V/50 Hz
Dimensions (W x D x H) | 480 x 555 x 1230 mm

Scope of delivery

Defro Firewood Plus 15 kW natural draft boiler

Analog boiler thermometer

Electronic fire draft regulator

Chain for the fire regulator

Short-circuit valve

Vertical grate insert

Wirbulators

Cleaning tool

Operating and assembly instructions

Assembly & Safety instructions

Installation and commissioning must only be carried out by a qualified specialist company.

To comply with efficiency and emission requirements, a buffer storage tank with a capacity of at least 800 liters must be provided. The applicable national regulations regarding hydraulic integration and the exhaust system must be observed.

FAQ

1. For which buildings is the 15 kW version suitable?
For single-family homes with medium heating requirements or renovated existing buildings.

2. What log length is suitable?
For the 15 kW version, the recommended log length is 250–290 mm.

3. Is operation in a closed heating system possible?
Yes, thanks to the integrated safety heat exchanger, operation in a closed system is permitted.

4. Is a buffer storage tank required?
Yes, the recommended minimum capacity is 800 liters.

5. Can an induced draft fan be connected?
Yes, an optional induced draft fan can be controlled via the electronic control system.

6. What type of power supply is required?
230 V/50 Hz for electronic control.

Conclusion

The Defro Firewood Plus 15 kW combines classic natural draft technology with modern electronic controls. An efficient and robust solution for economical heating with firewood.