Getting your AC through hurricane season in Miami

Before the season: tie-downs, pad and drain

Miami-Dade's wind code requires outdoor units to be anchored to their pads with approved hardware. Walk out and look at yours: rusted straps, loose bolts or missing hardware mean the unit can shift or tip in high wind, kinking the refrigerant lines and tearing the wiring. A pad that has sunk or cracked won't hold an anchor well.

The storm season also overlaps the rainiest months, so it's a good time to have the condensate drain flushed and the float switch tested. A spring tune-up covers both, along with the capacitors and contactor that storms and power surges tend to finish off.

When a storm is coming

Switch the system off at the thermostat, then at the breaker for the outdoor unit. Clear loose items from around the unit that could be thrown against it. Photograph the unit and its nameplate for insurance.

Covering the outdoor unit is only safe while it's off, and the cover has to come off before the system runs again. A covered unit can't move air across its coil.

After the storm: don't switch it straight back on

Look before you restart. If floodwater reached the unit, if it moved or tilted on its pad, if the copper lines look kinked or the insulation is torn, or if debris is lodged in the fan guard, leave it off and call. Water in the electrical components or the base pan can cause a short the moment power returns.

Salt spray is the slower damage. Near the water, a storm can leave salt deposits on the coil that speed up corrosion over the following weeks. A gentle freshwater rinse of the coil, with the power off, helps; a technician can do it as part of a post-storm check.

Questions to ask at a pre-season visit

When a technician checks the system before the season, ask them to look at the tie-downs and pad, the disconnect and wiring for corrosion, whether a surge protector is fitted, and whether the unit sits where water pools in heavy rain. Ask how to shut the system down before a storm and what they want to see before it is restarted. It is a short conversation that saves a lot of guesswork when a storm is two days out.

If you have a generator, ask whether it can safely run the AC at all, and which circuits it should carry. Many portable generators cannot start a central air conditioner, and trying can damage both.

Power surges and restoration

Outages and the moment power comes back are hard on compressors and control boards. A surge protector at the outdoor disconnect is inexpensive compared with those parts. When power returns, wait a few minutes before switching the AC back on, and if the system trips its breaker or makes unusual noises, turn it off and call.