The DEFRO Optima Eko boiler has been designed for heating single-family houses, holiday homes, and modernized buildings. The unit combines high energy efficiency with reduced emissions while ensuring comfortable day-to-day operation. The model complies with Class 5 requirements according to PN-EN 303-5:2012 and the Ecodesign directive, confirming its environmentally friendly performance.
This bottom-combustion boiler is manufactured from certified boiler steel, and its water jacket is based on a durable structure with a multi-pass flue gas channel system. The vertical heat exchanger equipped with turbulators enhances heat transfer efficiency and reduces harmful emissions. The fixed cast-iron grate ensures long service life and facilitates easy cleaning.
The enlarged loading chamber allows for extended operation between fuel refills. The boiler can also burn seasoned split logs as supplementary fuel. Thanks to the use of natural chimney draft, the unit does not require an electrical power supply. It can operate with a heat buffer tank, a domestic hot water cylinder, and a 4-way mixing valve, enabling integration with both gravity-fed and forced circulation heating systems.
The DEFRO Optima Eko model is equipped with a secondary air supply control system and the option to install a draft regulator, allowing precise combustion control without the need for advanced automation. The boiler can operate in open and closed systems (in accordance with PN-B-02413:1991), provided appropriate safety measures are applied. Its simple design and intuitive operation ensure reliable and long-term use.
The unit meets the requirements of support programs such as “Clean Air”. Its high energy efficiency class translates into economical fuel consumption and reduced environmental impact. Low emissions and high thermal efficiency make this model a modern solution among solid fuel boilers.
Standard equipment:
water grates, movable grates, analog thermometer, vertical grate, tilting flap, boiler service tools, turbulators.
Optional equipment:
adjustable feet, draft regulator, safety fittings, BVTS thermostatic valve, thermal safety relief valve with automatic refill (series 544 / DBv2), blower kit.
| Parameter | Unit | 12 | 16 | 20 |
|---|---|---|---|---|
| Boiler output | – | 12 | 16 | 20 |
| Fuel | – | hardwood logs – birch | ||
| Loading chamber capacity 1 | kg | ~14 | ~19 | ~23 |
| Efficiency at nominal output | % | 89.1 | 89.2 | 89.4 |
| Energy efficiency class | – | A+ | ||
| Max. permissible operating pressure | bar | 1.5 | ||
| Required chimney draft | Pa | 17 | 19 | 21 |
| Max. supply water temperature | °C | 75/90 | ||
| Boiler weight 2 | kg | 350 | 378 | 409 |
| Water capacity | l | 81 | 97 | 102 |
| Flow and return connection diameter | inch | G 1” | G 1½” | G 1½” |
| Flue outlet diameter | mm | Ø 159 | Ø 178 | Ø 178 |
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