As the hot summer sun starts to fade and the refreshingly cool weather of fall starts to settle in, residents of Melbourne start preparing their homes and yards for the winter. For many, that leads to the question of whether they ought to cover their outside air conditioning unit for the winter.

While it may seem like a smart idea, the fact is there are a number of reasons why you shouldn’t cover your AC unit in the winter. On top of not being needed, covering your outdoor air conditioning equipment can even cause problems.

Here, the professionals at The Chilly Pig 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. Your AC Unit Isn’t Damaged by Snow

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

2. Covering AC Systems can Encourage Mold

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

Mold and mildew not only have an undesirable odor, but they can also pose health risks, especially for people with respiratory issues or allergies. Also, the unwanted 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 hide out for the winter months. For many critters, a covered air conditioner is an ideal winter refuge.

Birds, mice, chipmunks and even rats commonly make winter dens inside covered air conditioners. Animals living in a covered air conditioner can cause many problems. Rats can chew through wires, insulation and other components, causing damage that may require costly repairs. Debris animals bring into the AC to make themselves a warm and comfortable place to get out of the cold weather can obstruct airflow and ventilation, reducing the efficiency of the unit and potentially causing it to overheat. Additionally, animal waste can result in unsanitary conditions and potent odors.

Leaving your air conditioner uncovered helps discourage creatures, because an uncovered AC gives them less shelter from the elements than a covered unit. That’s better for your AC—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 it's better that you don't cover your air conditioning equipment in the winter is because a cover restricts airflow through the unit. Adequate airflow is vital for the AC system because it assists heat exchange and enables the unit to cool effectively. When airflow is severely limited, the system has to work harder to achieve the desired temperature, causing greater energy consumption and strain on the components.

In addition, if you turn on your AC without knowing that the exterior unit is covered or because you simply forgot, it could result in a range of problems. One issue is that the shortage of correct airflow could cause the compressor to overheat, resulting in its failure or damage.  That’s why it is crucial to ensure the outdoor unit is free from barriers and is not covered to maintain the best possible airflow.

5. AC Maintenance Is More Effective Than Covering Your Air Conditioner

The bottom line is, it's a lot more effective to do a little maintenance for your cooling system than to cover your outside AC unit.

There are a number of key maintenance activities you should prioritize to ensure maximum operation and longevity of your AC unit. First, it’s wise to look at your outdoor AC unit regularly and pull out any debris such as leaves, sticks and dirt to promote proper airflow. Second, examine and clean the coils, fins and filters to make sure there isn't any dirt and dust buildup that would hinder effective heat exchange or airflow.

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