Should you cover your central air conditioner in the winter?

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Should you cover your central air conditioner in the winter?

As fall descends upon us, we know winter’s on its way. This time of year, there’s no shortage of tasks for homeowners to check off their to-do lists to prep their houses for the coming cold. The amount of winterizing that’s necessary will depend on the climate you live in, as well as the particulars of your home.

One long-standing debate — and a remarkably divisive one, at that — is whether you should cover your HVAC unit in the winter. HomeServe will settle it, once and for all.

Do You Need to Cover Your Central AC Unit in the Winter?

It makes sense, in theory, to cover your AC unit to protect it from the elements in winter, particularly if you live in an area that gets a lot of snow and ice. But the truth is that modern HVAC units were built and tested to withstand extreme temperatures and precipitation. They are made with materials capable of handling winter weather and have built-in drainage to get rid of winter precipitation and snow melt, so contrary to what you may think, most outdoor AC units don't actually need a lot of protection during winter months.

In fact, covering your air conditioning unit during winter can do more harm than good, because it may trap moisture and condensation in the unit, which can lead to mold and rust. That’s especially true for plastic covers, like a tarp, or covers made of other nonbreathable materials that can similarly foster mold growth and corrosion. What’s more, snug, air-tight covers can be very appealing to critters looking for a spot to cozy up during cold winter months, and the last thing you want is mice or other rodents making a nest in your AC unit — and they can squeeze into smaller spaces than you might think.

How to Cover Your Central AC Unit

Although an air conditioner cover isn’t necessary for the coldest months, it can be helpful to have some protection for your unit in the fall — or, if the area where you live doesn’t get all that cold, throughout the mild winter. Covering the top portion of your unit with an outdoor AC cover can help keep leaves, twigs, nuts and other falling debris from getting lodged in your unit, which can cause problems down the line.

Think of it like your AC unit putting on a windbreaker rather than a great big parka and snowsuit.

Here are a few tips:

• Choose a cover made from a breathable material. It isn’t meant to keep out air and water; it’s just going to prevent animals and plant debris from getting in the unit. Check with your HVAC manufacturer to see if there’s a specific weather shield top cover option that’s meant for your unit.
• Only cover the top of the unit. Choose a cover that feels almost too small for your central AC unit. Make sure it only covers the top and extends no more than 6 inches down each side. This will ensure that, although the top of your unit is protected, the unit still has plenty of room to breathe, preventing the trapped condensation buildup that can cause issues with rust or mold.
• Remove the cover promptly. Well before it’s time to turn the AC back on, make sure you remove the cover to give the unit some time to air out.

When Should You Cover Your Air Conditioner?

You should cover your central AC unit when you’re sure you’re done with it for the season, and before the leaves start to change and fall. For many in the U.S., that could be October or November, depending on the climate in your area.

If you choose to, you can remove the cover after all of the leaves have fallen, but before the snowy weather sets in. Otherwise, you can remove it in the spring before you turn your unit back on.

This story was produced by HomeServe Editorial and reviewed and distributed by Stacker.