It's 2pm on a Tuesday in June. You walk inside, expect that familiar cool air to hit you — and it doesn't. The house feels warm. You check the thermostat. It says 81°. The AC is running but nothing is happening, or worse, it's not running at all.

First: don't panic. Some of the most common AC failures in the Lowcountry have surprisingly simple fixes. Others do need a professional — but even then, knowing what you're dealing with before you call saves you time and helps your technician diagnose faster.

Here's how to think through it.

Start Here Before You Call Anyone

Check the thermostat first. It sounds obvious, but it's worth saying. Make sure it's set to COOL and the temperature is set below the current room temperature. Check the batteries if it's a battery-powered unit — a dead thermostat battery is one of the most common "my AC stopped working" calls we get, and it's a two-minute fix.

Check your circuit breaker. Head to your electrical panel and look for the breaker labeled AC, HVAC, or Air Handler. If it's tripped (sitting between ON and OFF), flip it fully off, then back on. A tripped breaker can cut power to your system completely. If it trips again immediately after resetting, stop there and call a professional — that's a sign of a bigger electrical issue.

Check your air filter. A severely clogged filter can cause your system to freeze up and stop producing cold air entirely. Pull the filter and hold it up to a light — if you can't see light through it, it's overdue. Replace it, then give your system 30–60 minutes to recover before assuming something else is wrong.

Look at the indoor unit for ice. If you see frost or ice on the refrigerant lines or on the unit itself, your system has frozen up — usually from a dirty filter, low refrigerant, or restricted airflow. Turn the system OFF and switch the fan to ON to let it thaw. This can take a few hours. Once thawed, replace the filter and try again. If it freezes up again, it's time to call.

Check the condensate drain line. Your AC removes humidity from the air and that moisture has to go somewhere — through a drain line. When that line clogs with algae or debris (which happens fast in the Lowcountry humidity), many systems have a safety float switch that shuts the whole unit down to prevent water damage. Look for a small PVC pipe near your indoor air handler, usually draining outside or into a utility sink. If it's clogged, sometimes a wet/dry vac on the end of the line can clear it. This is one of the most common summer service calls we make.

What These Symptoms Usually Mean

AC runs but the house won't cool down — Could be a dirty filter, low refrigerant, frozen coil, or a system that's undersized for the heat load on an extreme day. Start with the filter. If that's clean and the system is running normally, low refrigerant is the likely culprit — that requires a certified technician.

AC turns on and off repeatedly (short cycling) — This usually signals low refrigerant, a refrigerant leak, an oversized system, or a failing compressor. Don't ignore this one. Short cycling puts serious wear on your equipment and will shorten its life significantly.

AC won't turn on at all — Check the thermostat, the breaker, and make sure the disconnect switch near your outdoor unit hasn't been accidentally flipped off. If all of those check out, it's likely electrical or a failed capacitor — a quick, inexpensive fix for a technician but not a DIY job.

Warm air blowing from vents — If the fan is running but the air isn't cold, low refrigerant or a failing compressor is the most common cause. This one needs a pro.

Unusual noises — banging, screeching, or rattling — Banging usually means something is loose or broken inside the unit. Screeching can indicate a failing motor bearing. Rattling often means debris in the outdoor unit. Turn it off and call — running a system that's making these sounds can turn a moderate repair into a full replacement.

When to Skip the DIY and Call Immediately

Some things are genuinely not worth troubleshooting yourself. Call a certified technician if:

• The system is freezing up repeatedly after a filter change

• You smell burning or electrical odors coming from any part of the system

• Your breaker keeps tripping after being reset

• The outdoor unit is making loud banging or grinding noises

• The system is over 12–15 years old and struggling — it may be time for a replacement conversation rather than another repair

One More Thing Worth Knowing

In the middle of a Lowcountry summer, a failed AC isn't just uncomfortable — it can be a health issue, especially for elderly family members, young children, or pets. If your system fails and you can't get same-day service, get fans circulating, close blinds on sun-facing windows, stay hydrated, and consider spending the hottest part of the day somewhere with air conditioning while you wait.

We're Here When You Need Us

At Legacy Home Helpers, our HVAC-certified technicians serve Summerville, Goose Creek, Ladson, Charleston, and the surrounding Lowcountry — and we know how urgent an AC failure feels in June. Whether it's a quick diagnostic, a refrigerant recharge, a frozen coil, or a clogged drain line, we'll get to you fast and tell you exactly what's going on before any work begins.

Don't sweat it out longer than you have to.

Legacy Home Helpers | Summerville, SC | 843-212-6934 | legacyhomehelpers.com

Licensed technicians. HVAC certified. Serving the Lowcountry.

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