As the sweltering summer sun starts to fade and the cooler temperatures of fall starts to settle in, residents of Mobile start preparing their homes and yards for the winter. 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 good idea, the truth is there are a number of reasons why you shouldn’t cover your AC unit in the winter. On top of not being necessary, covering your outdoor air conditioning equipment can even cause problems.

Here, the professionals at Farnell Heating & Air Conditioning Inc share five reasons why covering your AC doesn’t need to be on your fall to-do list and what you should do instead.

1. Snow won't Hurt Your AC

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

2. Covered AC Systems may Encourage Mold Growth

One of the reasons you shouldn’t cover your AC unit in the cold months is because doing so can trap moisture—which is not at all what you want in your outdoor unit. That’s because trapping moisture inside the unit generates the perfect conditions for mold and mildew to thrive.

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

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

3. Covered AC Systems Can Host Animals

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

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

Leaving your air conditioner uncovered helps dissuade wildlife, because an uncovered AC gives them less shelter from chilly temperatures than a covered unit. That’s better for your air conditioner—and leaves you with less mess to throw away and things to repair in the spring.

4. A Winter Cover for AC Units Restricts Airflow

Another reason not to cover your AC unit in the winter is because a cover limits airflow through the unit. Suitable airflow is essential for the AC system because it assists heat exchange and enables the unit to cool properly. When airflow is reduced, the system has to work harder to reach the desired temperature, causing additional energy consumption and strain on the components.

In addition, if you turn on your air conditioner without knowing that the outdoor unit is covered or because you simply forgot, it could result in a range of problems. One issue is that the lack of proper airflow could cause the compressor to overheat, leading to its failure or damage.  That’s why it is essential to ensure the outdoor unit has no obstructions and is not covered to maintain maximum airflow.

5. AC Maintenance Offers More Benefits 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 a number of key maintenance projects you should prioritize to ensure the best possible function and longevity of your AC unit. First, it’s a good idea to inspect your outdoor AC unit regularly and clear any debris such as leaves, sticks and dirt to promote proper airflow. Second, examine and clean the coils, fins and filters to make sure you don't see any dirt and dust buildup that would hinder effective heat exchange or airflow.

Routine air conditioning maintenance not only improves efficiency, but it also helps extend the unit's life span, decreases energy consumption and avoids costly repairs. Rather than using a cover, putting time and effort into routine air conditioning maintenance is a proactive plan of action that can substantially benefit your entire HVAC system in the long run.