Weak airflow at vents, rooms cooling unevenly, and longer run times than normal.
Pull the return filter and hold it up to light. If light barely passes through, it is restricting airflow.
Replace filter, verify static pressure and blower performance, and inspect evaporator coil for airflow damage.
System runs in fan mode, starts and stops unpredictably, or never reaches set temperature.
Confirm thermostat is on Cool, set at least 3 degrees below room temp, and has fresh batteries if applicable.
Test thermostat calibration, wiring, control voltage, and stage calls to restore accurate cooling demand.
Warm supply air, longer cycles, possible hissing noise, and ice on copper lines.
Look for frost on refrigerant lines or the indoor coil panel. Do not keep running the system if icing is visible.
Locate leak, perform sealed-system repair, evacuate, and recharge to manufacturer specifications.
Little to no airflow, AC runs continuously, water near air handler after thawing.
Turn thermostat from Cool to Off and fan to On for thawing. Check if airflow improves after ice melts.
Confirm airflow and refrigerant conditions, clean coil as needed, and correct underlying freeze cause.
Outdoor unit runs hot, cooling is weak in afternoon heat, and utility costs increase.
Inspect condenser fins for cottonwood, grass, or dirt buildup around the cabinet.
Perform coil-safe cleaning, verify fan amperage, and measure split temperature to confirm heat rejection.
Outdoor unit hums, clicks, or struggles to start while indoor fan may still run.
Listen for repetitive clicking at outdoor unit. Do not open electrical panels.
Test and replace failed start/run components and verify compressor/fan startup under load.
AC may stop cooling suddenly and thermostat appears normal, often after heavy humidity days.
Check for standing water near air handler or drain line overflow at primary pan.
Clear drain restriction, test safety switch operation, and confirm proper drainage slope and flow.
System runs but temperature does not drop, sometimes with unusual vibration or electrical odor.
Shut system off if burning smell or hard-start behavior is present and call immediately.
Perform electrical/mechanical diagnostics, isolate failed component, and provide repair versus replacement options.