As the scorching summer heat starts to fade and the refreshingly cool weather of fall starts to settle in, residents of The Bay Area start preparing their homes and yards for the the upcoming cold weather. For many, that leads to the question of whether they should cover their exterior air conditioning unit for the winter.

While it may seem like a smart idea, the reality is there are many reasons why you shouldn’t cover your AC unit in the winter. In addition to not being something you need to do, covering your outdoor air conditioning equipment can even cause problems.

Here, the experts at Contra Costa Heating & AC share five reasons why covering your air conditioning equipment doesn’t need to be on your fall to-do list and what you should do instead.

1. Your AC can Handle Snow

Exterior AC units are designed to withstand harsh weather conditions like snow in the wintertime. These systems are built with solid materials and components that can handle the outdoor elements without damage. The coils and fins of the unit are engineered to resist corrosion, and the housing is crafted to protect the internal parts from moisture and debris.

2. Covering Your Air Conditioner Can Cause Mold

One of the reasons you should not cover your outdoor air conditioning equipment in the wintertime is because doing so can trap moisture—which is not at all what you want in your outdoor unit. That’s because allowing moisture to collect inside the unit produces the perfect conditions for mold and mildew to thrive.

Mold and mildew not only have an undesirable smell, but they can also pose health risks, especially for people with respiratory issues or allergies. Plus, the trapped moisture can corrode the internal components of the AC unit.

As an alternative to covering the unit, instead provide proper drainage and keep the area around the unit clean of debris, allowing for efficient airflow and preventing moisture buildup.

3. Covered AC Systems Can Attract Animals

Humans aren’t the only ones who get ready for winter. Animals that live around your home are also looking for a warm, cozy place to crash for the winter months. For many critters, a covered air conditioner is the perfect winter dwelling.

Birds, mice, chipmunks and even rats frequently make nests inside covered air conditioners. Animals living in a covered AC unit can cause many problems. Rats can chew through wires, insulation and other parts, causing damage that may require pricey repairs. Debris animals bring into the AC to create a warm and comfortable nest can impair airflow and ventilation, reducing the efficiency of the appliance and potentially causing it to overheat. In addition, animal waste can result in unsanitary conditions and foul odors.

Leaving your air conditioner uncovered helps dissuade wildlife, because an uncovered AC offers less shelter from chilly temperatures than a covered unit. That’s better for your AC—and leaves you with less mess to pick up and things to repair when winter is over.

4. A Winter Cover for AC Units Restricts Airflow

Another reason it’s better that you don’t cover your air conditioner in the winter is because a cover restricts airflow through the unit. Adequate airflow is crucial for the AC system because it facilitates heat exchange and allows the unit to cool effectively. When airflow is restricted, the system has to work harder to reach the desired temperature, leading to additional energy consumption and strain on the components.

In addition, if you use your air conditioning without realizing that the outside unit is covered or because you simply forgot, it could result in a range of problems. One issue is that the lack of appropriate airflow could cause the compressor to overheat, leading to its failure or damage.  That’s why it is necessary to ensure the outdoor unit is always cleared of any blockages and is not covered to maintain the best possible airflow.

5. AC Maintenance Works Better Than Covering Your Air Conditioner

The bottom line is, it’s a lot more effective to do a little maintenance for your air conditioning unit than to cover your exterior AC unit.

There are several key maintenance projects you should prioritize to ensure the best possible performance and longevity of your AC unit. First, it’s a good idea to look at your outdoor AC unit regularly and clear any debris such as leaves, twigs and dirt to allow proper airflow. Second, check and clean the coils, fins and filters to make sure there isn’t any dirt and dust buildup that would impede efficient heat exchange or airflow.

Routine air conditioning maintenance not only enhances efficiency, but it also helps extend the unit’s life span, lowers energy consumption and protects against costly repairs. Rather than using a cover, committing time and effort into routine air conditioning maintenance is a proactive approach that can substantially benefit your entire HVAC system in the long run.