The answer to 'how does replacement work' is that when your HVAC system needs to be replaced, it typically involves removing the old system and installing a new one. This is usually necessary when the existing system is no longer able to efficiently heat or cool your home, has become unreliable, or is nearing the end of its lifespan.
The replacement process typically involves an HVAC technician assessing your home's heating and cooling needs, selecting the appropriate new system, disconnecting the old system, and then installing the new one. This may include updating ductwork, electrical connections, and other components to ensure the new system is properly integrated into your home's infrastructure.