Weather can be unpredictable, no matter the season. Whether it’s a heavy rainstorm in the spring or leaves falling by the handful in the fall, your outdoor AC unit is exposed to a lot throughout the year. That’s why many homeowners start to wonder: Do you really need to cover your outdoor AC unit?
It’s a fair question. After all, your air conditioning system is a big investment, and it sits out in the open all year. Let’s break down why covering your AC unit is something you should avoid and how you can protect your system the right way.
Reasons Not to Cover Your Outdoor AC Unit
While covering your outdoor AC unit might sound helpful, it can actually do more harm than good. It’s important to be aware of the potential risks before you wrap your unit in plastic or toss a tarp over it.
Trapped Moisture and Mold
If moisture gets trapped under the cover, it creates a perfect environment for mold and mildew to grow. Instead of protecting the unit, the cover could speed up corrosion or rust.
Critters and Insects Move In
Covers can provide shelter for mice, bugs, and other pests. Once they get inside, they might start chewing on wires, building nests, or leaving behind waste. That can cause real damage and lead to costly repairs in spring.
Reduced Ventilation
Even if the unit isn’t running, it still benefits from airflow. Blocking off the entire unit cuts off ventilation and can create pockets of trapped humidity. This isn’t great for metal parts, especially ones like copper tubing or stainless steel elements.
Ice and Snow Can Still Get In
Covers don’t necessarily stop freezing rain, ice, or snow from entering through the bottom or sides. In fact, moisture can get sealed in, freezing overnight and damaging the compressor or fan motor. The trapped water can also increase pressure on interior components, including refrigerant lines.
Interferes With Maintenance
Seasonal cleanings and inspections can catch issues like clogged coils, damaged pumps, or restricted airflow early. Covers can hide these signs of wear or create new problems altogether. That makes routine maintenance harder and more expensive in the long run.
The Truth About AC Covers: What Types Cause What Damage?
Not all covers are created equal, but nearly all of them introduce some level of risk. Here’s how the most common types stack up:
Plastic Tarps
While they might keep out rain and sunlight, plastic tarps are notorious for trapping moisture. They create a humid environment, especially after a winter storm or heavy rain. With nowhere for water to escape, mold and mildew form on interior components and even under the base, where soil erosion can weaken the foundation.
Plywood Covers
Wood might sound breathable, but placing plywood over your condenser or heat pump blocks airflow and ventilation. The stagnant air creates condensation, which can lead to rusting of the compressor, fan, or metal brackets. Plus, wood can rot over time, further polluting the area with decaying organic matter and attracting insects.
Store-Bought Fitted Covers
Even “breathable” fitted covers aren’t risk-free. They may prevent hail or falling debris from trees or a nearby roof, but they often become nesting spots for squirrels, spiders, and other pests. Worse, these covers can trap air pollution, dust, and leaf debris, which lowers energy efficiency and increases wear on coils.
DIY Patio or Garden Covers
Some homeowners try building a little shelter using lattice, wood, or patio roofing. While this is better than a full wrap, it still limits sunlight exposure that helps dry the unit naturally. If airflow is restricted, humidity lingers around the coils, accelerating corrosion or internal pressure imbalances.
Maintenance Matters More Than Covers
The truth is that routine maintenance often matters more than any cover. Seasonal cleanings, checking refrigerant levels, and making sure the duct and ventilation system are in good shape can protect your AC far better than a tarp.
Schedule regular service calls to spot problems early and avoid surprises later. You can always ask your technician for honest advice about whether or not you should cover your central air conditioner based on your specific setup and yard.
If you’re looking for trustworthy help, Connors Plumbing, Heating & Air offers AC services in Waseca, MN, and the surrounding areas. Our technicians can give your system a full check and let you know what really matters for your home’s unique conditions.
The Bottom Line
So, should you cover your central air conditioner when the weather cools or leaves start to fall? All in all, it’s usually not worth the risk. Fully covering the unit can trap moisture, which leads to rust, and it can also create a cozy hiding spot for pests. That combination tends to cause more harm than good. If you still prefer to use a cover, we recommend covering just the top of the unit and not using a full cover. In most cases, routine maintenance and keeping the unit clean are the best ways to protect your system year-round.
Call Us Today for Honest, Friendly Service!
At Connors Plumbing, Heating & Air, we recognize how important it is to feel confident about your home’s systems. Since 1949, our family-owned business has helped families across Waseca, Owatonna, and Mankato keep their homes running without a hitch. Our team is known for being friendly, professional, and respectful of your property.
Whether it’s time for routine maintenance or you need an AC repair in Waseca, MN, we’ll get it done right. Give us a call today to schedule a service appointment!