HERESS, the hot air recovery system for wood-burning stoves
InfoWeb Marketplace · Editorial teamPublished on 14 November 2022 · 3 min read
In France, in 2021, sales of domestic wood-burning heating appliances rose by 34,4% compared with 2020*. Less polluting, this heating method is the most economical on the market, unlike other energy sources (fuel oil, electricity, gas, etc.). To optimize the performance and efficiency of a wood-burning stove, and thus make use of the heat it produces in all the main rooms of the house, not just the living room, the appliance can be fitted with a hot air distribution system.
For more than 30 years, DMO has been designing and marketing innovative solutions for chimney sweeping, air treatment and hot air distribution. To effectively optimize the efficiency of the wood-burning stove and save on heating bills, DMO offers a hot air recovery system: Heress. Made in France, the Heress system is easy to install and, when coupled with the hot air unit, redistributes heat evenly throughout the home for the greatest comfort of the occupants.
* Source: Observ'ER study - Renewable Energy Observatory - May 2022
Heress - Air recovery system for wood-burning stoves: how does it work?
Heress is a casing fitted with fins that is placed at the top of the flue and through which ambient air circulates. The fins optimize heat recovery. As it rises along the wall of the flue, the air heats up. The hot air then passes into the adjustable, ceiling-mounted plenum, which is connected by a duct to the DMO hot air unit. Installed in the attic, this unit blows and redistributes the hot air through a network of ducts to the air outlets located in the living areas.
A system that optimizes stove efficiency
The energy recovered by the DMO Heress system provides additional heating of up to 2000 W*, in the main rooms served by the distribution network. Black in color, the Heress system blends perfectly with the flue and does not detract from the interior decor. Its installation requires no modification to the existing installation.
* Spread over 2 to 6 rooms. Tested with the 4/6-room hot air unit.
Hot air recovery, filtration and distribution
The hot air is drawn from the fireplace hood using a semi-rigid aluminium intake duct of class M0 connected to a motorized distribution unit. After the fireplace has been running for a few minutes, the distribution unit starts automatically, and the hot air is filtered in a G4 box, then conveyed through a network of thermally and acoustically insulated ducts to the outlets that diffuse the purified hot air into the living areas.
A high-performance air recovery system for controlled consumption
Installed in the attic, the RUBIS 550 m3/h DMO hot air unit is very quiet. It starts automatically a few minutes after the fire is lit. The motor speed adapts to the desired room temperature.
A radio-frequency receiver - connected to the RUBIS unit and to a power supply (230V-50Hz) - and a mobile programmable radio-frequency room thermostat make it possible to control the temperature in the room where the thermostat is installed. In addition, a G4 filter box can be connected to the RAC RUBIS to filter the hot air before it is diffused into the rooms. This ensures good indoor air quality. The RAC RUBIS is suitable for a duct network of 2 to 8 air outlets, and its 6 speeds allow it to adapt to the required installation. Depending on the motor speed, power consumption varies between 30 and 117 W and the average flow rate of each outlet ranges from 50 to 70 m3/h depending on the chosen configuration.