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Do I Need to Cover My Air Conditioner During Winter?

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Tom Lohr is an avid home improvement enthusiast. He prefers to spend the money he saves on new tools and gardening supplies.

Are outdoor and window air conditioner units safe through the winter?

Are outdoor and window air conditioner units safe through the winter?

Should You Cover Your AC in the Winter?

Your air conditioner is your friend. It keeps your home from becoming a sweltering jungle during summer, cools your bedroom so you can sleep better, and likely costs as much as your first car. Despite refrigerated air being a relatively new invention, few of us can imagine living without it. If you were born later than 1980, you probably don't remember your world without it. Trust me, you can live without it, but not near as comfortably.

Most people, especially those that live in hot climates, would rather give up cable, internet, vacations, and at least one meal a day than give up air conditioning. And we all dread the day when we have to call the AC repairman to bring our loved one back to life, and we fear even more the day we have to fork out the cash to replace it.

Your air conditioning unit (we are talking out the unit that sits outside of your house) is a costly investment and is closely linked to our summertime quality of life. Being such an important part of our 21st-century life, we obviously want to keep it running as long as possible. Nothing is more depressing than flicking on the air conditioning during the first hot day of the year and nothing happens.

As winter approaches and you begin to winterize your house, what should you do with your air conditioner? The seemingly obvious choice would be to cover it up to keep the snow and weather out of it. But is that really necessary?

It is important to keep leaves and other autumnal debris out of the AC unit's top grate.

It is important to keep leaves and other autumnal debris out of the AC unit's top grate.

When to Cover Your Air Conditioner

Most people believe that covering an air conditioner during the fall and winter is a good way to keep snow, ice, and other debris from entering the fairly wide gaps on the top grating.

Protect Your Outdoor AC Unit From Leaves and Other Debris

In actuality, outdoor AC units are designed to withstand harsh winters. The real enemy is leaves, nuts, and other autumn-related hazards. If your unit is close to trees, especially trees that bear nuts or acorns, you most definitively should use an AC unit cover. But only cover to the top, sliding a sleeve-like covering over the unit will trap moisture and hasten the demise of your unit. Top only covers are affordable and readily available.

When Not to Cover Your Air Conditioner

As previously stated, winter is not a major concern for your unit. They are designed to remain uncovered during the coldest months. And just like using a full-length covering during the fall, during the winter, it will trap moisture to promote rust.

AC Unit Coverings Attract Rodents

There are, however, some fans of wintertime AC coverings. Rodents love them. Rodents view a covered AC as a great place to set up camp for the cold months. It will trap some warmth and keep the precipitation away. And they can build a lovely nest in it. Great for the rodents, not good for your AC unit.

AC units don't need to be protected from cold temperatures, just falling debris.

AC units don't need to be protected from cold temperatures, just falling debris.

AC Unit Covers Aren't Necessary for Winter

You should cover your AC unit with a top-only cover during fall only if leaves, nuts, and other debris are an issue. Otherwise, leave it uncovered. In winter, keep your unit uncovered until it is time to turn it on again.

Air Conditioner Unit Winter Maintenance

Despite the frigid temperatures, turn your AC on for a few minutes a month. This gets the parts moving a few times during the cold season and can help prevent equipment seizures. Only run it for a few minutes, and preferably when it is not below zero.

If the oil becomes too viscous due to the outside air temperature, it may not lubricate enough to prevent the unit from overheating. A minute or two per month will keep your AC at the ready for when you really need it.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.


Danny from India on September 06, 2020:

This is very informative, Tom. It's during summers that I find debris, mud, hairs, and other external materials getting in and settling inside the duct. Only recently when I switched on the AC and kept it at the lowest degree, i found mud residue all over my pillow.

We need to open the outer cabinet and clean the inner space. Asthmatics and respiratory illness are also aggravated when the AC spews debris out.

Liz Westwood from UK on September 06, 2020:

Air conditioning units come top of our list when choosing accommodation in warm climates. Not many homes have it in the UK currently, but there are some hot days in the summer that make us all ponder it. No doubt, in the future more of us will get air conditioning. Given the English weather in winter, your article is very useful.