According to estimates by the World Health Organization, approximately 44,000 people die prematurely each year in Poland due to excessive air pollution. The European Commission brought a lawsuit against Poland to the European Court of Justice in Luxembourg in 2015 for failure to comply with EU air quality legislation. Due to poor air quality, Poland has been threatened with penalties that could reach €1 billion. Although Poland has managed to significantly reduce emissions from industrial plants, a very serious problem with low emissions persists. This article aims to identify the main sources of low emissions in Lubuskie Province and to indicate the environmental benefits resulting from the modernization of the central heating system, involving the replacement of boilers. The article points out that reducing low emissions from boilers in private houses, due to its significant share in air pollution and the fact that this is an underreported problem, could bring a significant positive ecological effect. Analysing the issue from an economic viewpoint, it should be noted that replacing inefficient coal-powered boilers so far provides the largest ecological effect in relation to the investment costs.