HVAC units, which stands for Heating, Ventilation, and Air Conditioning, are systems designed to control the indoor climate of buildings. They provide heating during cold weather, cooling during hot weather, and ventilation to ensure fresh air circulation. These units can be found in homes, offices, and various commercial spaces. There are different types of HVAC units, including central air conditioning systems, furnaces, and heat pumps. Each type serves a specific purpose and can vary in size and efficiency. Proper maintenance of HVAC units is essential for optimal performance and energy efficiency.