<p>Heating, Ventilation, and Air Conditioning (HVAC) systems represent a major share of building energy consumption, creating both operating cost and emissions reduction challenges for energy communities. This work proposes an optimisation-based management framework for a community of buildings, integrating HVAC operation with renewable generation, battery storage, and demand-side flexibility. The methodology employs a mixed-integer linear programming model to coordinate thermal and electrical energy flows, considering indoor comfort constraints, equipment dynamics, and market price signals. The framework is validated through a case study using real demand, weather, and market data, comparing baseline and optimised operation under varying seasonal conditions. Results demonstrate significant reductions in total operating cost and peak demand of the energy community, alongside improved usage of renewable generation and reduced reliance on the grid, without compromising thermal comfort. The proposed approach highlights the potential of coordinated HVAC scheduling in energy communities as a pathway toward more cost-efficient and sustainable building operation.</p>