Should I Cover My AC Unit in the Summer?

HVAC Logo IconBy Tom MoorAugust 1, 2023

Central air conditioning systems play a crucial role in keeping families safe and comfortable during the summer, so it’s only natural to protect the system so it operates properly and efficiently. This may include regular AC maintenance, air filter changes, and removing debris near the outdoor condenser unit. To provide additional protection for their AC units, some homeowners ask – “should I cover my AC unit in the summer?” Keep reading to learn more about what an AC cover is and whether you should install one.

What Is an AC Cover?

An air conditioner cover keeps leaves, twigs, dirt, snow, rodents, and other debris out of the system in hopes of preventing system damage. Some homeowners also worry water from snow and rain will damage the system’s components. However, today’s AC units are weather-resistant and highly durable to withstand the harshest weather conditions.

Several types of air conditioner covers are sold online or available at big-box stores. Many are constructed with water-resistant polyester and cover either the top of the condenser or the entire unit. They range in price from about $10 to over $100.

Should I Use an Air Conditioner Cover in the Summer?

Most heating and air conditioning experts recommend not using an AC unit cover in the summer as a protective measure for a few different reasons, including:

Moisture Damage

Protecting air conditioners from moisture damage is the main reason homeowners install air conditioner covers in the summer. However, an AC cover may produce the exact opposite effect. Condensation, humidity, and other natural elements often find a way inside the system, and the cover will actually trap the moisture in the unit. This can lead to rusted components and damage.

“The presence of excess moisture can lead to corrosion of internal components, such as the condenser coils or electrical connections,” said Ben Green, owner of Green Leaf Air in Richardson, TX. “Corrosion can compromise the unit's efficiency and lead to costly repairs or even the need for a full replacement.”

Airflow Restriction

AC condenser covers can also restrict airflow to the unit. Proper airflow is necessary to allow the air conditioner to expel heat effectively.

“When the cover obstructs the unit’s intake and exhaust vents, it may lead to reduced cooling performance and increased strain on the compressor,” Green said. “Over time, this added strain can cause the AC unit to work harder, leading to increased energy consumption and potential premature component failure.”

Heat Trapping

AC covers, especially non-breathable models, can trap heat inside the system. Higher operating temperatures can reduce the system’s efficiency and shorten the lifespan of components.

Mold and mildew

If an AC outdoor unit cover traps excess moisture inside, mold and mildew can grow which can be harmful to the health of you and your family members.

Critters

Homeowners also install air conditioning covers to prevent rodents, pests, and other critters from nesting in the AC condenser unit. But, again, this can backfire, as the cover can also provide a warm, cozy place for rodents to nest, especially during colder weather.

Should You Cover Your Air Conditioner in the Winter?

It may seem like a good idea to use air conditioner covers for winter, especially if you live in an area with frequent ice and snow. Modern air conditioning systems, though, are manufactured to withstand the harshest weather year-round and contain built-in drainage systems to eliminate precipitation from snow. Just like in summer, using an AC condenser cover for winter can lead to mold, rust, and rodent infestations.

It might make sense to use an HVAC cover in the fall if your system is surrounded by trees. Adding the proper AC unit cover for a few weeks when the leaves and pine needles fall can offer your system a level of protection.

“If your yard is heavily tree covered, I would consider putting something on top of it to stop the leaves from going through the grill and winding up at the bottom of the cabinet,” said Gary Hullfish, president of Lawrenceville Fuel in the Trenton, N.J. area. “However, I would never cover it in the spring and summer. Just let it dry out after the rain.”

Invest in Regular AC Maintenance

To keep your air conditioning system running smoothly throughout the warmer months, invest in regular AC maintenance each year before the start of the warm-weather season. During an AC tune-up, an HVAC technician will perform several tasks, including:

  • Checking the thermostat settings
  • Lubricating all moving parts
  • Tightening the electrical connections
  • Checking system controls
  • Inspecting the condensate drain
  • Checking the refrigerant levels
  • Cleaning the condenser and evaporator coils
  • Adjusting and cleaning blower components

A couple of DIY maintenance tips to consider include changing your HVAC air filter regularly and clearing any twigs, branches, or other debris from around your condenser.

FAQs on AC Covers

Is it a good idea to cover your AC?

It’s generally not considered a good idea to cover your AC. Although homeowners who cover their air conditioners have good intentions, AC unit covers can trap moisture inside the system which leads to mold and a nesting ground for rodents and pests.

Should you use a window AC cover?

Many HVAC technicians do not recommend using window AC covers because they can trap moisture inside the unit which causes mold and rust.

Does covering the outside AC unit help?

Most experts say covering the outside AC unit does not help and often causes more harm than good. You may want to consider covering your outside AC condenser for a few weeks in the fall to prevent leaves and pine needles from becoming lodged inside the system.