Generally speaking, you do not want to cover your air conditioning unit during the winter. We have explained this in great detail mentioning the risks of animals, mildew and other weather-related issues in previous posts. But there are a few exceptions to the rule.
Keep your Unit Debris Free:
With the weather changing and winds blowing debris and garbage become not only an issue in your gutter but also builds up in your AC unit as well.
Although external AC units are meant to withstand the weather, this does not mean that they will look brand new after a decade of harsh weather. Lawn debris may be blown in, paint will fade and rust may eventually develop in places.
If done properly, covering can help slow a general weathering of the unit to include paint and rust proofing as well as debris buildup. As mentioned before however, it is important to ensure that there is a healthy air flow through the unit and a regular cleaning to remove leaves and pine needles is a good idea.
One helpful idea is check your weather for the random “sunny day” in the off season. Once you have determined the weather will cooperate, go ahead and pull off your cover for the day. This allows the air flow we have been talking about while keeping your mind at ease for any further damage.
Look Up for Falling Ice:
Unless your have a rooftop unit most of your standard placement for the systems can be placed as an external AC unit near or under a roof. If your rooftop is one that experiences ice buildup, there is a danger that falling ice could cause damage.
Some professionals recommending using a piece of plywood can serve as a protective roof for the unit while at the same time allowing airflow. In fact, damage from falling ice is one of the more common causes of repair calls in the springtime.
If your external AC unit is far enough away from your house or you live in a climate doesn’t see much icing, this type of covering may be entirely unnecessary, but it does avoid the problems of moisture buildup, rodents and mold that other covers can cause. It is always better to be safe than sorry.
Severe Hailstorms and Blizzards:
Depending on where you live and your climate change hailstorms and blizzards can become more of a pain than you think. Your average storm won’t affect an external AC unit but damaging hail storms and severe blizzards may. In this case, proving a temporary cover before a blizzard strikes is a wise move as it prevents snow from building up inside and damaging the coils.
Hail storms can be unpredictable and are not limited to the winter months, but if severe enough, the battering can have an impact on your unit. In the case of hail, a simple plywood cover that allows airflow is again your best bet. Always check your weather beforehand and avoid trying to be out in storm. Your best bet is to be prepared and have everything covered before your find yourself struggling in dangerous weather conditions.
In a nutshell, only cover your AC if there is a “special occasion” that warrants the extra effort and added risks. And then, make sure to follow some best practices for how to cover that AC.