ROJEK KTP 25 natural draft boiler for logs – 25 kW
The ROJEK KTP 25 is a hand-fed Natural draft boiler for firewood With a nominal output of 25 kW, the boiler operates without a fan, relying solely on natural chimney draft, and is suitable for the reliable heat supply of single-family homes, agricultural buildings, or small commercial units.
Important: The boiler is sometimes referred to as a wood gasifier. Technically, however, it is a classic wood gasifier. Log-fired natural draft boiler. Combustion occurs via natural chimney draft and is mechanically controlled by air dampers and a thermostatic draft regulator. This means the KTP 25 uses simple, robust, and durable heating technology.
Highlights
- ⭐ Natural draft boiler for firewood without combustion fan
- ⭐ 25 kW heating output for residential buildings and smaller commercial properties
- ⭐ Robust welded steel construction
- ⭐ Thermostatic draft regulator for automatic power control
- ⭐ EN 303-5 certified solid fuel boiler
Area of application & Target audience
The ROJEK KTP 25 is suitable for buildings with medium heating requirements. Typical applications include:
- Single-family homes and larger residential buildings
- Workshops and agricultural buildings
- Renovation projects with existing chimney systems
- Wood heating systems in combination with buffer storage
Natural, untreated firewood is used as fuel. A maximum wood moisture content of 20% is recommended for efficient combustion.
Everyday benefits
Thanks to the simple natural draft principle, the boiler operates without complex electronics or fan technology. This makes the heating technology particularly robust, durable, and low-maintenance.
The generous combustion chamber allows for longer burning times and reduces the number of refueling intervals in daily heating operation.
Technology & equipment
The boiler consists of a robust welded steel construction with a water-cooled grate. Combustion takes place via natural draft through the chimney.
- adjustable primary and secondary air
- thermostatic draft regulator RT3
- integrated pressure gauge and thermometer
- Integrated after-cooling loop for overheating protection
- Connection flow/return G 2"
The recommended chimney draft is approximately 8–12 Pa.
Efficiency & Environment
The boiler meets the requirements of the European standard. EN 303-5 for solid fuel boilers.
- Efficiency: approx. 75%
- Energy efficiency class: A+
- Exhaust gas temperature at rated power: approx. 220–300 °C
The use of a buffer storage system is recommended for efficient and low-emission operation.
Technical data
| Manufacturer | ROJEK |
| Model | KTP 25 |
| Boiler type | Log-fired natural draft boiler |
| Rated power | 25 kW |
| Minimum performance | 15 kW |
| combustion chamber volume | 61.6 liters |
| Water volume | 109 liters |
| Max. log length | 43 cm |
| Flue pipe diameter | 159 mm |
| Max. operating pressure | 2 bar |
| Max.Operating temperature | 90 °C |
| Weight | 301 kg |
| Energy efficiency class | A+ |
Scope of delivery
- ROJEK KTP 25 boiler
- Operating instructions
- Thermostatic pull regulator RT3 with chain
- Heating system outlet valve 1/2"
- Side ceramics
- alignment screws
Assembly and safety instructions
Installation must be carried out by a qualified heating contractor. A safety group and a correctly installed after-cooling loop are required.
Only dry firewood may be used as fuel. The use of liquid fuels for kindling is not permitted.
FAQ
Is the ROJEK KTP 25 a wood gasifier?
No. The KTP 25 operates as a classic natural draft boiler for logs and not according to the wood gasification principle.
Does the boiler require electricity?
Not for the boiler operation itself. Electricity is only needed for the heating circulation pump.
What length of wood can be used?
The maximum log length is approximately 43 cm.
Is a buffer storage tank necessary?
Not technically required, but recommended for efficient operation.
What chimney draft is required?
The recommended chimney draft is between 8 and 12 Pascals.
What is the optimal wood moisture content?
A residual moisture content between 12% and 20% is recommended.
Suitable system components
