In St. Augustine's year-round Florida heat, a properly sized and installed AC system is essential — not optional. New AC installation in St. Augustine typically costs between 3,500 and 8,000, depending on system size, efficiency rating, and whether ductwork modifications are needed.
In St. Augustine's hot, humid climate, proper sizing is critical. A load calculation (Manual J) is the industry standard. A rough guide: 1 ton per 400–500 sq ft, but St. Augustine's heat and humidity often require slightly more capacity. An undersized system runs constantly; an oversized system short-cycles and leaves you humid.
Florida requires a minimum 15 SEER2 for new installations. Many St. Augustine homeowners choose 18–20 SEER2 systems for energy savings — with Florida's long cooling season, the efficiency upgrade often pays back in 4–6 years.
A standard central AC replacement takes 4–8 hours. New installations requiring ductwork can take 1–3 days. Plan for your home to be warmer than normal during installation.
Yes — St. Johns County requires permits for AC installation and replacement. Your licensed HVAC contractor will pull the permit and schedule the required inspection. Never skip this step; unpermitted HVAC work can cause insurance and resale issues.
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