A Guide to Air Conditioner Maintenance Plus Useful Tips

Air conditioner maintenance is the key to ensuring your air conditioning unit can keep your house cool even on the hottest days. Air conditioners rely on regular maintenance to work their best. Regular upkeep like replacing filters, cleaning coils, and more will ensure your AC unit runs well and efficiently, saving you money on your utility bill.

While it’s best to keep up with air conditioner maintenance as needed, you should plan on performing AC maintenance in the spring to ensure your AC is ready for the summer heat waves. Below, we’ve outlined steps for performing air conditioner maintenance so you can skip the service call to an HVAC technician.

How to Maintain Your AC Unit

1. Replace Interior Filters

   Replacing interior filters isn’t something you should wait until spring to do. In fact, you may need to replace your return filters more than once a month, especially if you have pets in your home.

   Tip

   If you have a hard time remembering to change your filters, sign up for a filter subscription service, which delivers a filter to your door when it’s time for a new one. You can set the interval to match your home’s needs, so you’re never without a fresh filter.

2. Remove Debris

   Once a month, head to your outside unit and visually inspect the area around it.

   Remove any debris on and around the unit, including mulch, leaves, sticks, and more. As this debris builds up, it can block the unit’s airflow, which will compromise performance.

3. Clean the Coils

   Once you remove all debris on and around the unit, clean the coils on the outside unit.

   About every three months, spray the unit down with coil cleaner following the manufacturer’s instructions for proper application and wait times. If specified, rinse off the cleaner.

4. Clean and Straighten the Fins

   The fins on the outside unit are prone to crushing due to everyday impacts such as rocks thrown by lawnmowers, sticks falling from trees, string trimmers, and more, which hinder airflow.

   After cleaning the coils, use a fin straightening tool to gently straighten the fins. It may take a few passes to straighten severely crushed fins.

5. Clean the Condensate Drain

   Your AC unit relies on the condensate drain to shed the moisture that is created during the cooling process.

   Over time, the condensate drain can get clogged and it must be cleaned out. Take time once every few months to inspect the condensate drain and do a light cleaning.

   To locate the condensate drain, look for a pipe (typically white PVC) coming out of your unit. Some AC condensate drains are fitted with a tee for easy cleanout. You can simply remove the cap if present, then clean out the condensate line using vinegar and a pipe cleaner.

6. Clean the Evaporator Coil

   Dust, hair, and other debris can reach the evaporator coil, which typically sits inside the interior component of your HVAC system. Just like the outside coil, the evaporator coil should be inspected and cleaned about every three months.

   Once you’ve turned off the power to your unit, you can remove the outside cover and reveal the evaporator coil inside. You may need to remove another interior cover to see the evaporator coils.

   Use a flashlight to inspect the coils and gauge how dirty they are. If you see noticeable dirt and debris, follow these steps to clean the evaporator coil:

   1. Use a stiff brush to gently remove as much debris as possible.
   2. Vacuum out the debris.
   3. Spray a foaming coil cleaner on the evaporator coil and let it sit for 5 minutes or as long as specified on the bottle.
   4. If the bottle instructs you to rinse the cleaner, gently do so with a pump-style sprayer.

7. Clean the Evaporator Drain

   If you’ve cleaned out your condensate drain line but you still don’t have a steady flow of water, the drain beneath the evaporator could be clogged. After cleaning the evaporator coil, clean the entire area beneath the coil and unclog the drain.

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When to Hire a Professional

While all the AC maintenance tasks above can easily be completed by DIYers, many are better left to professionals.

Things like measuring and recharging refrigerant, changing capacitors and other electrical components, swapping fans and fan motors, servicing or replacing compressors, and more are better left to a trained professional who has the tools and know-how to get the job done right. Additionally, handling refrigerant requires licensing in many regions.