Hurricane season and your AC: a Jacksonville homeowner's checklist

Before the storm

Walk around the outdoor unit. Move patio furniture, grills, planters and anything else that could be thrown against it. Trim dead branches nearby if there's time. Don't wrap the unit tightly in plastic; trapped moisture does more harm than good, and you'll need to remove it before running the system anyway.

If you have a maintenance visit due, getting it done before peak storm season means the drain is clear and the electrical connections are tight, which helps the system cope with the power fluctuations that come with storms.

Cool the house, then shut it off

Some homeowners cool the house a few degrees below normal before the storm arrives, so it stays comfortable longer if power goes out. Then, before the high winds reach you, turn the system off at the thermostat and at the breaker.

The reason to shut it off is power quality. During storms, power can flicker, drop and surge repeatedly, and those swings are hard on compressors, capacitors and control boards. A system that's off can't be damaged by them.

When the power comes back

Wait until power has been stable for a while before turning the system back on. Early restoration often comes with more flickers as crews work. Restoring power at the breaker first and then at the thermostat, after a pause, gives the system a gentler start.

If you run a portable generator, never connect it to the house wiring without a proper transfer switch, and never run it indoors or in a garage. A portable generator generally can't run a central AC safely anyway.

Check the unit before restarting

Look for debris lodged in the fan guard or against the coil, a unit that has shifted on its pad, bent refrigerant lines, or damaged electrical conduit. If the outdoor unit was underwater, don't run it; flood water can ruin the electrical components and the compressor, and it needs a technician's inspection first.

Near the coast, strong onshore winds drive salt spray inland. A gentle freshwater rinse of the outdoor coil after the storm, once it's safe, removes salt before it starts corroding the fins.

Signs something was damaged

After restarting, watch for warm air, unusual noises, a burning smell, breakers tripping, or the outdoor unit humming without the fan turning. A power surge commonly takes out capacitors and control boards, and those failures show up the first time the system tries to start.

If anything seems off, turn it back off and call. Running a damaged system can turn a small repair into a big one.

Protecting against surges

Power surges during and after storms are one of the most common causes of post-storm AC failures. Turning the system off before the storm is the best free protection. Some homeowners also add a surge protector at the outdoor disconnect, which can help absorb spikes that would otherwise reach the capacitor, contactor and control board.

A whole-home surge protector at the electrical panel is another layer. Either way, the goal is the same: keep damaging voltage swings away from the most sensitive parts of the system.

Mold and humidity after an outage

A long outage in summer lets indoor humidity climb quickly. Once power is back and the system checks out, run it on cool with the fan on auto to bring moisture down. If the house stayed closed and hot for several days, look for musty smells or visible growth around vents and in closets, and consider having the coil and drain checked, since standing water in the pan can grow slime.

After the season

Once storm season winds down in late fall, a check of the outdoor unit, the drain and the electrical connections catches anything the season loosened. It's also a good time for the heating check before the first cold night.