The answer to 'how does installation work' is that HVAC installation is a complex process that requires specialized knowledge and tools. It typically involves removing the old system, preparing the space, installing the new equipment, connecting the electrical and ductwork, and testing the system to ensure it's working properly.
The installation process can take several hours to a full day or more, depending on the size and complexity of the job. It's important to hire a licensed and experienced HVAC technician to handle the installation, as they have the expertise to ensure the system is installed safely and efficiently.