The article investigates HVAC (heating, ventilation, and air conditioning) technologies aimed at mitigating Primary Energy (PE) consumption in renovated buildings. This research is part of a broader initiative focused on enhancing air quality and reducing the carbon footprint within the fields of architecture and urban planning. Conducted since 2018 by a team from the Institute of Architectural Design at the Department of Contemporary Architecture, Faculty of Civil Engineering and Architecture, University of Technology in Lublin, the study exemplifies the application of these technologies at the historic Marshal Piłsudski’s “Milusin” Manor House in Sulejówek, near Warsaw. The primary objective of this research is to present HVAC solutions, particularly a free cooling and heating system, which are specifically tailored for the renovation of historic structures. This technology effectively recovers thermal energy from groundwater, achieving low energy consumption levels while simultaneously minimizing CO2 emissions.