A significant proportion of the worlds increasing energy demand required for space heating of buildings, which has a high relevance for environmental impact. In private households the change of a heating system promotes energy efficiency and reduces energy consumption noticeably. Despite many initiatives in this field, such as government regulations and promotional campaigns, the renovation rate of heating systems are low worldwide. The fundamental research questions of this thesis therefore are when and why households opt for a new heating system, which factors play a role in the decision-making process and which people influence the decision. To answer these questions scientific studies by the aid of literature search, citation and text analysis and Web mining are examined, categorized and compared. Individuals usually choose a new heating system because of dissatisfaction with the status quo or restoration activities, are influenced in the decision-making process by judicial, economic, environmental, demographic as well as technology- and building-specific factors and besides information from the media and they use people in the social environment like family members or neighbours as well as energy consultants as interpersonal sources of information.