Close collaboration between Cogra and Harman permitted the development of the first air tight combustion circuit * in the world in 2005!
From that date on, all models in the range have benefited from this innovative feature.
Our ability to anticipate gave us the opportunity to show the way to a major technological improvement.
What is a device air tight combustion circuit?
These stoves use as combustion air, the air taken from outside the home, more specifically so, in the concentric (Dualis EDPA air intake part) which is then channeled thru the wood pellets in the burner.
The stove operates regardless of the conditions inside the home; i.e. ventilations, kitchen hood and so on. The ambient air heating circuit is independent of the combustion circuit and there is a perfect seal between the two.
It is thus impossible for smokes to leak inside the room, even in case of power failure.
The channeled combustion air has then been preheated in contact with the flue combustion products, which largely improves performance.
As a result, all the air entering the combustion circuit is actually being used for fuel oxidation. No outside air can then enter the stove thru its wide open door or structure even.
Hence, the control of the combustion together with the resulting efficiency and a clean combustion is perfectly achieved.
What are our measurements?
We make it our policy to achieve perfection in this field with a view to stifle any possible objection; hence we chose the system of reference applied to gas appliances.
The leakage rate of Harman stoves is about 800 l / h for 50 Pa.
This rate can be compared with sealed appliances requirements.
For example: according to EN 613 « self-regulating gas-fired convection heaters » which applies to C11 type appliances, the seal test is 0.25 m³ / h per kW to 12 kW and 3 m³ / h above 12 kW.
Decree No. 2008-1231 of 27 November 2008 (prevention of CO poisoning) (see ADEME)
*Order of August 2, 1977
Order of June 9, 2009 (Title V certification in RT 2005)