Why Covering Your AC Unit In Winter Is A Recipe For Unwanted Visitors

As winter approaches, homeowners are always looking for ways to protect their homes from the cold temperatures, blustery winds, snow, and ice. If you've prepared your pipes, cleaned the gutters, and brought in your potted plants, you may be eyeing your outdoor AC unit as the next item to check off on your list. Covering it seems to make sense — it can't be good for the unit to have all the snow and ice pile up directly on top of it. However, before covering up your AC unit in the winter, it's important to understand that a cover could put the unit at risk for a pest infestation. A fully covered AC unit provides a warm, safe spot where rodents, birds, lizards, and other critters are protected from the cold, snow, and ice, so these pests will nest inside all winter long. By the time you uncover your unit in the spring, they may have done serious damage to the AC.

This potential risk may seem worth it to protect the AC unit from snow and ice, but the system actually doesn't require any protection against the elements. It features durable, weather-resistant materials that withstand corrosion and tolerate moisture exposure. In fact, your AC unit requires air to flow freely around it, so the internal components can dry out after rain or snow. In addition to encouraging pests to make the unit their home, a cover can also prevent it from drying out, which can cause mold to grow.

AC units are costly investments, so you are probably interested in tips to prolong the life of your HVAC system. Preventing rodents and other pests from making a winter home of your covered AC unit can certainly help. That's because mice, rats, squirrels, chipmunks, birds, lizards, opossums, and other critters can destroy vital components of the system. Invading animals often bring in debris, such as leaves, grass, twigs, and feathers, for their nests, which can pose a fire risk or block airflow in the unit when you turn it on in the spring.

Mice and other rodents also have a habit of chewing through wiring and insulation. In some cases, they'll even use these materials to help build their nest. This type of damage can cause a short in your HVAC system or become a potential fire hazard. Pests that live in your AC unit also urinate and leave droppings inside. Animal urine is extremely caustic, so it can corrode the metal components.

Depending on the type of pests that take up residence in your covered AC unit, you may even be in for a confrontation come spring. Larger critters, such as squirrels or opossums, may not appreciate being disturbed in their safe haven when you uncover the unit in the spring, which can put you at risk for an attack. So when it comes to prepping your home for cold weather, it's best to skip the AC cover.