Domestic waste combustion in central heating furnaces is illegal in many countries, including Poland, but unfortunately still occurs. These activities have a negative influence on the environment and human health. The local nature of this process makes it difficult to effectively counteract this phenomenon. Information campaigns about the impact of domestic waste combustion in central heating furnaces, especially the impact on human health, are necessary, but undertaking parallel control activities is much more important. To control activity, support is necessary to develop a suitable method to confirm domestic waste combustion in central heating furnaces. In the present preliminary study, we have investigated two methods. The first method is indirect, it is based on the analytical pyrolysis of organic residues in ash and provides direct information on the type of plastic subjected to combustion. The second method is based on the principal component analysis (PCA) of polycyclic aromatic hydrocarbon (PAH) concentrations in ash samples. Special attention was paid to sixteen PAHs: naphthalene, acenaphthene, acenaphthylene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, chrysene, benzo(a) anthracene, benzo(a)pyrene, benzo(e)pyrene, benzo(b+k)fluoranthene, dibenzo(a,h)anthracene+ indeno(1,2,3-cd)pyrene, benzo(g,h,i)perylene, and perylene.