Five things to check yourself
- Thermostat: set to Cool, and the set temperature is below the room temperature. A thermostat on Fan Only moves air without cooling it.
- Filter: a clogged filter starves the system of airflow and can freeze the indoor coil. If it is gray and packed, replace it and give the system a few hours.
- Breaker and outdoor disconnect: the indoor blower can run while the outdoor unit is off on a tripped breaker. If the outdoor fan is not spinning, that is the first thing to look at.
- Ice: look at the copper line at the indoor unit or the coil itself. Ice means the system should be turned off at the thermostat (fan on) to thaw before anyone works on it.
- Outdoor unit: leaves, cottonwood fluff or a fence crowding the condenser keep it from dumping heat. Clear a foot or two around it.
What it usually is in Louisiana
- Our humidity makes systems work harder and longer, so worn parts show up in July. Capacitors and contactors on the outdoor unit are common failures and are quick repairs.
- Low refrigerant means a leak. Topping off without finding the leak is a short-term fix; ask what was found.
- A dirty evaporator or condenser coil cuts capacity. On older systems in New Orleans, a coil cleaning can restore cooling for the season.
- If the compressor itself has failed on an older system, that is the point where a repair-versus-replace conversation makes sense.
When to call
- Call if the outdoor unit is not running, if you see ice, if the breaker trips again after a reset, or if the air is still warm an hour after the checks above.
- Tell the crew what you checked. It shortens the visit. You hear the visit fee on the phone before anyone is scheduled.
General guidance from the U.S. Department of Energy on home air conditioning. A diagnosis by a technician is the only way to know what your system needs.