The article explores HVAC systems, which are essential for maintaining comfortable indoor temperatures and air quality in buildings. HVAC systems can be central or local, with primary equipment including heating, ventilation, and cooling units. Central HVAC systems are located outside buildings and use ductwork to distribute conditioned air. Different types of central systems include all-air, air-water, and all-water systems. Key components of central HVAC systems are heating and cooling panels, as well as water-source heat pumps.