The expense of a fresh HVAC system in San Diego can differ significantly depending on the size and variety you necessitate. Generally, installation costs range from $3,000 to $7,500 for an average-sized home. The exact price will depend on factors such as the brand and model chosen, the complexity of installation, additional features or components needed (such as ductwork), and labor costs. It's important to get quotes from several reputable contractors before making your decision.