March 2026 · Soligo Air
Florida's heat puts more stress on AC systems than almost anywhere else in the US. When your system stops working — especially in the middle of summer — it's almost always one of a handful of common causes. Here are the 8 most likely reasons your AC stopped working in Florida, starting with the ones you can check yourself.
Check your electrical panel first. AC systems have dedicated double-pole breakers (usually labeled AC, HVAC, Air Handler, or Condenser). If a breaker is tripped to the middle position, switch it fully off then back on. If it trips again immediately, there's an electrical fault that requires a technician — don't keep resetting it.
This is the most Florida-specific cause on the list. Most AC systems have a float switch that shuts the system off completely when the condensate drain pan overflows. Florida's humidity means your system removes massive amounts of water from the air — and algae clogs these drain lines constantly. Look for standing water in the drain pan under your air handler. If you find it, the float switch has triggered a safety shutdown. Clear the drain line with diluted vinegar.
Capacitors help start and run the compressor and fan motors. They're one of the most common components to fail — especially in Florida's summer heat, which dramatically shortens capacitor lifespan. A failed capacitor often causes the outdoor unit to hum but not start, or the system to run but not cool. This is a technician repair but typically quick and affordable ($150–$250).
A severely restricted filter can cause the system to overheat and trip a high-limit safety switch, shutting the system down entirely. Replace the filter and reset the system (turn it off at the thermostat for 5 minutes, then back on). If the system starts normally after a filter change, that was your problem.
Ice buildup on the indoor coil blocks airflow completely, causing the system to stop cooling even though it's running. Caused by restricted airflow (dirty filter, blocked vents) or low refrigerant. Turn the system to FAN ONLY for 2–3 hours to thaw the coil. If it freezes again, you have a refrigerant or airflow problem that needs professional diagnosis.
The contactor is a relay switch in the outdoor unit that connects power when the thermostat calls for cooling. When it fails, the outdoor unit won't run even though the indoor unit is blowing air. You may hear a humming sound from the outdoor unit. This requires a technician but is similar in cost to a capacitor replacement.
Low refrigerant causes the system to progressively lose cooling capacity until it can no longer maintain setpoint, eventually triggering safety shutdowns. Signs include ice on the refrigerant lines, warm air despite the system running, and a hissing or bubbling sound. Refrigerant leaks must be found, sealed, and recharged by a licensed technician — handling refrigerant without EPA 608 certification is illegal in Florida.
Sometimes the system itself is fine but the brain controlling it has failed. Try replacing thermostat batteries first. If the thermostat display is blank or showing incorrect readings, the thermostat may need replacement ($150–$400 installed). Control board failures are less common but more expensive ($400–$900) and require professional diagnosis.
Quick checklist before calling: thermostat set correctly → circuit breaker checked → filter replaced → drain pan inspected for water. If all clear and system still won't work, it's time to call a technician. Soligo Air offers same-day diagnosis across Orlando, Sanford, Clermont, and all of Central Florida.
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