outdoor HVAC unit covered in snow

As the scorching summer sunshine starts to fade and the relief of fall starts to settle in, residents of Sacramento start preparing their homes and yards for the wintertime. For many, that leads to the question of whether they ought to cover their exterior AC for the winter.

While it may seem like a good idea, the truth is there are several 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 professionals at Bishop’s HVAC share five reasons why covering your air conditioner 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 winter season. These units are built with durable materials and hardware 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 shouldn’t cover your air conditioner 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 produces the perfect conditions for mold and mildew to flourish.

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

Rather than covering the unit, instead make sure the unit has proper drainage and keep the area around the unit cleared of debris, allowing for efficient airflow and preventing moisture buildup.

3. A Covered Air Conditioner Can Attract Animals

You and your family aren’t the only ones who prepare for winter. Animals that live around your home are also searching for a warm, cozy place to hide out for the winter months. For many animals, a covered air conditioner is an awesome winter refuge.

Birds, mice, chipmunks and even rats frequently make nests inside covered air conditioners. Animals living in a covered air conditioner can cause several problems. Rats can chew through wires, insulation and other connections, causing damage that may require pricey repairs. Debris animals bring into the AC to create a warm and comfortable place to get out of the cold weather can block airflow and ventilation, lowering the efficiency of the appliance and potentially causing it to overheat. In addition, animal excrement can result in unsanitary conditions and potent odors.

Leaving your air conditioner uncovered helps deter animals, because an uncovered AC offers less shelter from the elements than a covered unit. That’s better for your AC—and leaves you with less mess to pick up and things to repair once the snow melts.

4. An AC Cover Restricts Airflow

Another reason not to cover your AC unit in the winter is because a cover blocks airflow through the unit. Proper airflow is crucial for the AC system because it assists heat exchange and allows the unit to cool properly. When airflow is reduced, the system has to work harder to achieve the desired temperature, resulting in greater energy consumption and strain on the components.

In addition, if you turn on your air conditioner without noticing that the outside unit is covered or because you simply forgot, it could result in a range of problems. One issue is that the absence of correct airflow could cause the compressor to overheat, causing 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 optimal airflow.

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

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

There are numerous key maintenance projects you should prioritize to ensure optimal performance and longevity of your AC unit. First, it’s a good idea to inspect your outdoor AC unit regularly and remove any debris such as leaves, sticks and dirt to maintain proper airflow. Second, check and clean the coils, fins and filters to make sure they are free from dirt and dust buildup that would prevent successful 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 avoids costly repairs. Rather than using a cover, putting time and effort into routine air conditioning maintenance is a proactive strategy that can substantially benefit your entire HVAC system in the long run.