ROJEK KTP 20 natural draft boiler for split logs – 20 kW
The ROJEK KTP 20 is a robust hand-fed natural draft boiler for split logs with a rated output of 20 kW.
The boiler operates without a fan, relying solely on natural chimney draft, and is suitable for reliable heat supply to
single-family homes, workshops, or smaller commercial units.
Unlike wood gasification boilers, combustion in the KTP 20 is based on the classic natural draft principle.
The combustion air is controlled via adjustable air flaps and a thermostatic draft regulator. As a result, the boiler operates
technically as a split log natural draft boiler with simple, durable technology.
Highlights
- ⭐ Natural draft boiler for log wood without a fan
- ⭐ 20 kW heat output for single-family homes and smaller buildings
- ⭐ Robust welded steel construction
- ⭐ Thermostatic draft regulator for output control
- ⭐ EN 303-5 tested solid fuel boiler
Application area & target group
The ROJEK KTP 20 is suitable for buildings with medium heat demand. Typical applications include:
- Private households and single-family homes
- Workshops and agricultural buildings
- Renovation projects with an existing chimney system
- Wood heating systems with buffer storage
Operation is carried out with untreated split logs with a recommended wood moisture content of maximum 20%.
Everyday advantages
The natural draft boiler operates without complex electronics or fan technology. This makes the heating technology
especially robust, low-maintenance, and durable. The output control is mechanical via the
thermostatic draft regulator, which automatically controls the air supply.
Thanks to the large combustion chamber, longer burn times are possible, which significantly increases comfort in daily
heating operation.
Technology & equipment
The boiler consists of a sturdy welded steel construction with a water-cooled grate.
Combustion takes place classically in natural draft mode via the chimney draft.
- adjustable primary and secondary air
- thermostatic draft regulator RT3
- integrated pressure gauge and thermometer
- cooling loop to protect against overheating
- connection flow/return G 2"
The required 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+
- Flue gas temperature at rated output: approx. 220–300 °C
For efficient and low-emission operation, combination with a buffer storage tank is recommended.
Technical data
| Manufacturer |
ROJEK |
| Model |
KTP 20 |
| Boiler type |
Log wood natural draft boiler |
| Rated output |
20 kW |
| Minimum output |
12 kW |
| Combustion chamber volume |
47.9 liters |
| Water volume |
98 liters |
| Max. log length |
33 cm |
| Flue pipe diameter |
159 mm |
| Max. operating pressure |
2 bar |
| Max. operating temperature |
90 °C |
| Weight |
261 kg |
| Energy efficiency class |
A+ |
Scope of delivery
- ROJEK KTP 20 heating boiler
- Operating instructions
- thermostatic draft 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.
Connection of a safety group and a correctly installed cooling loop is required.
Only dry split logs may be used as fuel.
The use of liquid fuels for lighting the fire is not permitted.
FAQ
Is the ROJEK KTP 20 a wood gasifier?
No. The KTP 20 operates as a classic natural draft boiler for split logs and not on 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 split log length is about 33 cm.
Is a buffer tank necessary?
Technically not mandatory, but recommended for efficient operation.
What chimney draft is required?
The recommended chimney draft is between 8 and 12 Pascal.
What is the optimal wood moisture content?
A residual moisture content between 12% and 20% is recommended.
Matching system components