15 AC Maintenance Tips Every Homeowner Needs to Know – Don’t Ignore These!

Summer is coming, and the last thing you want is your air conditioner breaking down on the hottest day of the year. Proper AC maintenance isn’t just for technicians—you can do many of these simple tasks yourself. Here are 15 maintenance tips that can help you keep your air conditioning unit in top shape and avoid expensive repairs.

1. Remove AC Cover Before Use

If you cover your AC unit during winter, don’t forget to remove it before turning your unit back on. Running your AC with a cover on can damage the unit and reduce efficiency.

2. Clean the Condenser Coil

The condenser coil collects dust, debris, and leaves over time, blocking airflow and decreasing efficiency. Simply hosing it down at the beginning of summer (and periodically) helps keep it clean. Avoid using harsh chemical cleaners as they may damage aluminum fins.

3. Check for Mouse Nests & Broken Wires

Critters love to nest inside AC units during winter. Check the electrical sections for nesting materials, wire damage, or broken connectors. Ensure all wiring is intact before running your AC.

4. Test the Dual Run Capacitor

The capacitor is a common point of failure. Use a multimeter to ensure it remains within its rated specifications. It’s a good idea to have a spare capacitor ready during peak summer months.

5. Inspect the Suction Line Insulation

The thick suction line should have insulation to ensure efficient cooling. If the insulation is worn out or missing, replace it to keep refrigerant temperatures stable.

6. Ensure the AC Unit Is Level

An uneven AC unit can stress components and lead to premature failure. If your unit sinks or tilts, carefully use a shovel to lift and level it by adding support materials underneath.

7. Test AC Early

Don’t wait for a heatwave—run your air conditioner when outdoor temperatures are around 60–65°F. This helps you catch any issues early so you have time to fix them before summer really kicks in.

8. Check for a Stuck Fan Motor

Sometimes, the fan motor may seize up after winter. If your fan isn’t moving or is barely spinning, try giving it a push with a screwdriver. If this happens frequently, the capacitor may be weak or failing.

9. Measure Temperature Differences

Use a thermometer to check the temperature difference between your return air and supply air—it should be between 15–20°F. A lower difference can indicate issues with airflow, refrigerant levels, or a dirty evaporator coil.

10. Clear the Condensate Drain Line

A clogged condensation drain can lead to water backups, damaging your furnace. Use compressed air or a bleach-water solution to clear the drain line and prevent blockages.

11. Change the Furnace Filter

Your AC relies on proper airflow. Replace your filter every 1-2 months for 1-inch filters and every 6-8 months for thicker filters. A clogged filter can lead to frozen coils and inefficient cooling.

12. Check the Blower Wheel

Dust accumulation on your furnace blower wheel restricts airflow, lowering efficiency. After turning off the power, inspect your blower wheel for dust buildup. If dirty, clean it thoroughly.

13. Turn Off the Humidifier

Many homeowners forget to turn off their humidifier during summer. Switch your humidistat to “off” and set the humidifier damper to the summer setting to prevent excess moisture buildup.

14. Don’t Close Too Many Vents

Closing too many supply registers can restrict airflow and stress your AC system. Keep at least two-thirds of your vents open to maintain proper cooling efficiency.

15. Replace Thermostat Batteries

If your thermostat uses batteries, replace them every few years to prevent unexpected malfunctions. Also, if you installed a new thermostat recently, ensure the jumper between R and RC is in place for power to cooling.

By regularly performing these maintenance checks, you can keep your AC running smoothly, improve efficiency, and minimize costly repairs. Do you have other maintenance tips? Share them in the comments below!

If you need professional assistance, contact E & R Heating and Cooling for a free estimate!