As winter approaches, many homeowners wonder if they should cover their outside air conditioning unit. An AC unit exposed to winter weather can potentially sustain damage, so covering it seems logical. However, most experts advise against covering your outdoor AC unit. There are a few exceptions, but in general, covering your AC can cause more harm than good.
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Quick Answers
Should you cover your outside AC unit in the winter?
In most cases, no. Leaving your AC unit uncovered is usually best to prevent moisture buildup and other potential problems.
What are the disadvantages of covering your AC unit for winter?
– Can lead to moisture buildup and corrosion
– Can provide shelter for pests
– Can cause overheating if cover is not removed in time for spring
– Potential for cover to blow away and damage unit
When is it OK to cover your outdoor AC unit?
– In extremely cold climates with frequent heavy snow
– If cover allows airflow and won’t trap in moisture
– Unit must be thoroughly inspected and cover secured
What precautions should you take if you do cover your AC unit?
– Use breathable, waterproof cover that won’t blow away
– Frequently inspect for moisture buildup
– Remove cover in early spring to prevent overheating
– Ensure proper drainage away from unit
Why You Should Not Cover Your AC Unit
The main reason not to cover your outdoor AC unit is that it can lead to moisture buildup inside the covered space. This moisture can cause corrosion and damage to the internal parts of your AC system. Here are some specific reasons why covering your AC unit is generally not recommended:
Trapped moisture causes corrosion
When you cover your AC unit, any moisture that gets inside the cover has nowhere to go. This creates a damp environment within the covered space, allowing corrosion to occur. The coils, wires, and other parts can corrode over time from this excess moisture exposure.
Pests can take shelter
A covered AC unit provides an attractive shelter for pests like rodents, spiders, and insects. They can nest in the warm, dry space and chew through wires or clog drainage areas. This can cause severe damage to your AC system.
Heat buildup when uncovered too late
If your AC unit has been continuously covered all winter, it can overheat when the weather warms up. If you forget to remove the cover in early spring, the trapped heat can damage your AC system.
Covers may blow away
Unless your cover is very securely fastened, wind gusts can catch the edge and blow the cover right off your AC unit. This leaves your system exposed to the elements and also creates a risk of accidental damage if the flapping cover hits your AC equipment.
Difficulty doing maintenance
Covering your AC unit makes it harder to do routine maintenance like coil cleaning. You either have to remove the cover each time or work around it and hope you can access all the necessary areas. Important maintenance keeps your AC running efficiently.
When Covering Your AC Unit is OK
There are a few circumstances when it may be alright to cover your outdoor AC unit:
Extreme cold climates
If you live in an area with a true winter climate of heavy snow and subzero temperatures, covering your AC unit may be beneficial. Just ensure the cover is breathable and moisture can escape. Remove the cover occasionally to check for snow buildup.
Using a waterproof, breathable cover
If you use a high quality, water-resistant cover that still allows airflow, covering your AC unit may not cause moisture issues. Look for covers made of waterproof, breathable materials without vents that can let in snow or rain.
Inspecting regularly for moisture
If you do cover your AC unit, inspect it frequently for any moisture buildup. Remove and wipe down any condensation you find right away before corrosion occurs. Checking it routinely can allow you to cover it safely.
Removing cover in early spring
As soon as temperatures begin rising in spring, take the cover off the AC unit. This prevents overheating issues when you turn the system on for cooling. Just remember not to accidentally leave it on too long.
Tips for Covering Your AC Unit
If you decide to cover your outdoor AC unit, here are some tips to do it properly:
Use breathable materials
Choose a cover made from a waterproof but breathable fabric, like Gore-Tex or Tyvek. Avoid plastic sheeting that will trap in moisture. The cover should repel water but allow air to flow through.
Allow for airflow
Avoid wrapping the cover too tightly. Leave space for airflow around the sides of the unit. Don’t press the cover flush to the top of the AC equipment.
Secure the cover
Use straps, ties, hooks, or other fasteners to keep the cover securely in place. Choose attachments that won’t blow loose in high winds. Check them periodically for slack.
Slope cover to divert water
Install the cover at an angle so precipitation drains away from your AC equipment. Water should run off the sides and not pool on the flat top surface.
Check drip pan and drainage
Before covering, clear debris from any drip pans or drainage holes around the base of your AC unit. This allows proper water runoff.
Inspect for pests first
Check around and under your AC unit to ensure no pests have begun nesting there. Remove any signs of pest activity before putting on a cover.
Conclusion
Most experts recommend against covering your outdoor AC unit, except for in very specific circumstances. In general, leaving your AC uncovered through winter is the safest option. Covers tend to trap in moisture and lead to corrosion, pest problems, and overheating issues come spring. If you do cover your unit, take precautions like using breathable materials, allowing for airflow, securing the cover properly, and frequently checking for moisture buildup. With careful maintenance, you may be able to cover your outdoor AC safely in areas with extreme winters. But for most climates, keeping your AC uncovered is typically the wisest choice. Just take care to divert water away from the unit and do occasional maintenance to keep your system in good shape through the winter.