A compendium of knowledge about HITZE fireplaces – Find answers to all your questions about our products.


The power of the fireplace depends primarily on the quantity and quality of the fuel loaded into it. To put it very simply, assuming that the fireplace has an efficiency of 80%, we can obtain approximately 3 kW of power from one kilogram of dry wood. For example, if the fireplace has a declared power of 14 kW, we can load it with 2 kg of fuel and obtain a power of 6 kW, and vice versa, if we want the fireplace to have a higher power, it is enough to throw 7 kg of wood into the combustion chamber and generate over 20 kW. power.

Therefore, the question arises: why should you choose them when choosing a fireplace or wood stove? rated power? To answer this question, you need to ask yourself another: what is rated power given by fireplace manufacturers? I'm in a hurry to explain.

Nominal power in the HITZE-1 fireplace
Nominal power in the HITZE-1 fireplace


Fireplace manufacturers and wood stoves in the specifications of their products they provide a parameter called nominal power. Nominal power of the fireplace is the power at which a given device performs best energy and emission parameters, i.e. high efficiency declared by the manufacturer and low emissions.

Nominal power devices is one of the most important parameters for this type of devices, because the dimensions of its combustion chamber are determined already at the design stage of the insert or free-standing furnace. The fireplace in the fireplace is adjusted to the size of the load and, consequently, to the power with which it will operate. Based on the amount of loading, a system is developed to aerate the combustion chamber, which precisely supplies the right amount of air to the combustion chamber to ensure ecological wood burning.

From depending on nominal power of the fireplace an appropriate heat exchanger is designed to allow for the most effective removal of heat generated during the combustion process.

The nominal power also allows you to determine how the fireplace should be used free-standing cooker so as not to cause it to permanently overheat. This allows you to maintain an appropriate level of security.


What if you still use the fireplace with too small/large load? The overall energy efficiency of the fireplace will decrease and its emissions will, in most cases, increase.

If the load is too large, the fireplace will be overloaded for a long time and its exchanger will not be able to absorb the appropriate amount of heat generated during the combustion process. Simply put, a large part of the energy will escape with the exhaust gases into the chimney. Additionally, the amount of air supplied to the fireplace will not allow for effective combustion of exhaust gases, and as a result, the fireplace's emissions will increase.

If the amount of wood is too small, the chamber will be underheated, which will result in deterioration of the exhaust gas after-combustion processes. There will be too much excess air in the combustion chamber, which will reduce the efficiency of the fireplace. Why? Because the energy generated during wood burning will be partially used to heat this so-called left air.

Therefore, burn according to the instructions provided with the fireplace and observe the required loading. Thanks to this, you will not only save money because the efficiency of your fireplace will be at a high level, but you will also burn it ecologically, which will translate into improved air quality in your area.


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