FIREWOOD AND PELLET BOILER
15 – 20 kW
Integrated particle separator
(electrostatic precipitator)
available as an option

Firewood and pellet boiler
NEW! S2 Dual compact
Two systems perfectly combined
The S2 Dual compact firewood and pellet boiler combines two perfect systems – it meets all the requirements for firewood and pellet fuels in two separate combustion chambers. Highly efficient and convenient – the S2 Dual compact ensures low emissions and low energy costs. The new LTC 5000 control system with 7″ glass touch display offers even more options for controlling the boiler. The swivelling flue pipe connection makes adapting to different types of installation possible, considerably facilitating installation. Optionally, an integrated particle separator ensures even lower emissions and fulfils the highest requirements for environmental friendliness. Proven features such as efficient carbonisation gas extraction, the speed-controlled induced draught fan, long refilling intervals and low power consumption make the S2 Dual compact a solution that is as economical as it is convenient. The S2 Dual compact also offers important advantages when installed in the boiler room: The compact design means that installation is child’s play, even when space is limited.
Froling offers a flexible solution for people who may want to use pellets in future: the S2 Turbo comes with a pellet flange as standard, which means that the pellet unit can be retrofitted at any time. This is supplied fully insulated and ready to plug in.

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The latest technology

Lambdatronic 5000 controller with 7" glass touch display for even easier operation
Air-cooled fuel loading chamber
Servo-motor for automatic control of heating, primary and secondary air
Water-cooled pellet flange
Practical, convenient ashcan for simple, dust-free emptying and long emptying intervals
Large pellet container with stoker screw and external suction module
High-quality insulation
Water-cooled pellet burner with slide valve for automatic ash removal and cleaning
Large fuel loading chamber for logs up to half a metre long
(up to 56 cm)
High-temperature firebrick-lined combustion chamber
Individual controller for the heating system
Lambdatronic 5000 controller
With the new Lambdatronic 5000 boiler controller and the modern 7″ glass touch display, Fröling is moving into the future. The new design is impressive, not only for its intuitive operation but also its numerous new features. The most important
components can be freely selected in the tile overview and information and error messages can be customised. For example, the control system will inform you when the ash box needs to be emptied. This makes operating and running the system even simpler and easier to understand. The intelligent control management enables the almost unlimited integration of heating circuits, storage tanks and hot water tanks.
Advantages
- Precise combustion control by a Lambda controller using a Lambda probe
- Connection of heating circuits, water heaters and buffer storage tanks Management systems
- Integration capability for a solar panel system
- LED frame for status display with illuminated presence detection
- Simple & intuitive operation
- Various SmartHome solutions (e.g. Loxone, Modbus TCP) Remote control from the Living room (room console) or via the Internet (froeling-connect.com)



Keep track of everything with the Froling App
The Froling App allows you to check and control your Froling boiler online from
anywhere, at any time. You can read and modify the main status information and settings easily and conveniently online. You can also specify which status messages you want to be informed about via SMS or e-mail (e.g. when the ash box is to be emptied or in the event of a fault message).
The app is available in the Android Play Store and iOS App Store.
Advantages
- Simple and intuitive operation of the boiler
- Status information can be called up and changed within seconds
- Individual naming of the heating circuits
- Changes of status are notified directly to the user (e.g. via
e-mail or push notifications) - No additional hardware required (such as an Internet gateway)
Smart Home
Loxone
Combine your Froling heating system with the Loxone Miniserver and the new Froling Extension and implement individual boiler control on the basis of the single room control of the Loxone Smart Home.
Modbus
Via the Froling modbus interface, the system can be integrated
into a building management system.
Brochures / EU Labels
Tecnical data
| Tecnical data - S2 Dual compact | 15 | 20 |
|---|---|---|
| Nominal output | [kW] | 15 |
| Output range - pellet mode | [kW] | 4,4 - 15 |
| Energy rating label (Efficiency label (boiler + controller) | A+ | A+ |
| Weight - firewood boiler / pellet unit | [kg] | 455 / 190 |
| Water capacity - firewood boiler / pellet unit | [l] | 90/15 |
| Fuel loading door dimensions - firewood boiler (width/height) | [mm] | 350/360 |
| Fuel loading chamber capacity - firewood boiler | [l] | 80 |
| Pellet container capacity (automatic feed) | [l] | 40 |
Dimensions

| Dimensions in mm - S2 Dual compact | 15 | 20 |
|---|---|---|
| L1 Length of the boiler (flue gas pipe connection at rear) | 1070 | 1070 |
| L2 Distance from the flue gas pipe top connection to the front face of the boiler | 915 | 915 |
| L3 Length, pellet unit | 860 | 860 |
| L4 Length, firewood boiler | 1000 | 1000 |
| B1 Total width including WOS lever | 1150 | 1150 |
| B2 Width, firewood boiler | 685 | 685 |
| B3 Width, pellet unit | 315 | 315 |
| B4 Width, boiler | 1000 | 1000 |
| B5 Distance between flue gas pipe connection and side of boiler | 585 | 585 |
| B6 Distance between flow connection and side of boiler | 450 | 450 |
| B7 Distance between return connection and side of boiler | 150 | 150 |
| B8 Distance between safety heat exchanger connection and side of boiler | 420 | 420 |
| B9 Distance between safety heat exchanger connections | 65 | 65 |
| B10 Distance between drainage connection and side of boiler | 890 | 890 |
| H1 Height of boiler | 1335 | 1335 |
| H2 Height of rear connection for the flue gas pipe | 1230 | 1230 |
| H3 Height of the flue gas pipe top connection | 1385 | 1385 |
| H4 Height of hose line connection | 1255 | 1255 |
| H5 Height, safety heat exchanger connection | 840 | 840 |
| H6 Height, return connection | 130 | 130 |
| H7 Height, drainage connection | 125 | 125 |
| H8 Height of connection for flow | 1125 | 1125 |
| Flue gas pipe diameter | 129 | 129 |
Operating and maintenance areas

| Minimum clearances - S2 Dual compact [mm] | 15 / 20 |
|---|---|
| A Clearance from insulated door to wall | 800 |
| B Door swing area | 500 |
| B1 Clearance from boiler side without pellet unit to wall | 815 |
| C Clearance from back side to walld | 400 |
| D Clearance from side of boiler to wall¹ | 500 (200¹) |
| E Maintenance area above the boiler² | 500 |
¹ The heat exchanger for the boiler is accessible for maintenance only from the front
2 Maintenance area for removing the WOS springs upwards
Tecnical documentation
For you personally
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