AC Running But Not Cooling in New Orleans: What to Check First

When the AC is running but the house will not cool down, the cause is usually one of a handful of things: restricted airflow, a refrigerant leak, a frozen coil, or a failing electrical component. Start with the checks below, then know what to hand off to a technician.

Safe Checks You Can Make

• Check the air filter. In humid, pollen-heavy air, filters can clog within a few weeks. If you cannot see light through it, replace it.
• Confirm the thermostat setting. Make sure it's set to COOL, not FAN, and set several degrees below room temperature. Check batteries if the display looks dim.
• Look at the outdoor unit. With the system off, clear grass clippings, leaves, or debris from around it so it can release heat properly.
• Check for water near the indoor unit. Standing water can indicate a clogged condensate drain, which can shut the system down.

What a Technician Has to Evaluate

• Low refrigerant. Warm air, ice on the copper lines, and rising bills can point to a leak, which requires an EPA-certified technician to locate and repair.
• A frozen evaporator coil. If the indoor coil has iced over, the system should be shut off and allowed to thaw before a technician diagnoses the underlying cause.
• A failing capacitor. Heat and long runtimes are hard on capacitors, which start the compressor and fan motor. A humming outdoor unit with a fan that will not spin often points here.
• Wiring or control issues. A loose connection or failed relay can let the fan run without the compressor engaging.
• An aging or undersized system. An older system may simply be struggling to keep up; a technician can evaluate whether continued repair still makes sense.