| Thermostat | Check the batteries. They may be dead, or the thermostat may be on the wrong setting. | Replace the batteries in your thermostat and double check that it’s on the cool setting. |
| Circuit breaker | The breaker switch may be turned off. | Flip the switch back to the “on” position. |
Not blowing cold air? | Air filter | The filter needs to be clean to do its job. If it’s clogged with dirt or dust, it won’t work. | Replace or clean your filter to allow air to blow better. |
| Outside unit | If the area around the unit has foliage, furniture or debris laying around it can stop air from flowing correctly. | Clear a two-foot space around your air conditioner and keep it clean so that nothing blocks the airflow from your unit. |
| Refrigerant | Leaking refrigerant will cause the unit to be less effective since there is not enough cooling fluid to work. | A professional HVAC technician can fix this for you. |
| Insulation | Without insulation, air can leak out from your home. Cracks, windows and doors are common areas where this happens. | Consider upgrading your windows to ones that are more insulating or use blackout curtains to keep the sun and heat out. |
Dripping water? | Condensate line | The pipe leaving your air conditioner may have debris inside it. | Use compressed air to remove the clog. |
| Drain line | If the drain pan is full, it can cause the drain line to be blocked and water to overflow. | See if there are any blockages in the drain line and clear them. Empty your drain pan as well. |
Making odd sounds? | Blower motor or belt | Squeaking sounds are typically from the belt or the blower motor. | Lubricant can help the parts to run smoothly without squeaking. |
| Fan blades | If the sound is like a card in a bicycle spoke, then it’s likely that something is stuck between the blades. | Turn off the unit, open it carefully and check if there is something caught between the blades and extract it gently. |