For heating purposes in modern households, gas burners are normally applied due to their simplicity, low cost and easy handling. On the other hand, practical experience showed that conventional, open flame gas burners compared to porous medium systems have low dynamic range, i.e. low power modulation capability and, additionally, higher production of pollutants such as carbon monoxide (CO) and nitrogen oxides (NO(x)). This is especially notable when the burner operates at low thermal power regimes. In order to avoid the above-mentioned difficulties and disadvantages of conventional burners, new porous medium gas burner system with maximum thermal output of 8 kW has been developed. The objective of the presented work is focussed on better understanding and enabling further developing of porous medium burners (PMB) for household heating systems. The aim of the work is also to develop a compact and highly efficient combined heating system based on the 8 kW gas PM burner coupled with a new heat exchanger incorporated into an electro-fossil fuel system considering space and domestic water heating in one-family house. The final result was the heating system with modulation of the thermal power up to approximately 1:8 and low emissions of CO and NO(x). (C) 2009 Elsevier Ltd. All rights reserved.