When it comes to taking care of your air conditioner during the offseason, there's plenty of advice to be heard — both good and bad. One piece of advice commonly heard by countless homeowners is that you must keep your outdoor AC unit covered if it's not being used. In reality, keeping your AC unit wrapped up throughout the winter could actually be bad for its health, as explained below.
1. Preexisting Protection
Outdoor AC units are built with outdoor usage in mind, featuring weather-resistant materials that are capable of enduring years of harsh weather conditions, including heavy snowfall and extreme cold. These materials often include rust-resistant stainless steel and copper. After all, your AC unit has to sit out in the open day in and day out for years on end and work perfectly while doing it.
2. Rodent InfestationTo the average small rodent in search of wintertime shelter, a covered AC unit seems like an oasis against the bitter cold. As long as the cover keeps snow and icy winds out, it can also hold in enough warmth to make any critter feel at home once they're inside. Once these pests have set up shop inside your AC unit, that's when the trouble starts.
Mice, squirrels, raccoons and other small rodents are notorious for gnawing through electrical wiring and foam insulation. The result of an ongoing infestation can easily hobble your AC system for days or even weeks as your HVAC technician works to undo the damage. In some cases, the damage may be enough to warrant a complete replacement of your HVAC system.
3. Moisture and Rust IssuesAC covers don’t have proper ventilation which allows moisture to become trapped within the AC unit. As that moisture builds up, it also increases the risk of your unit becoming susceptible to rust and corrosion. Although the various copper, aluminum and stainless steel components may resist rust buildup, the same can't be said for components made from ordinary steel.
Rust issues can make it difficult for the moving parts to move freely, creating unnecessary friction that could cause further damage. Heavy moisture buildup can also cause AC components to freeze solid under freezing temperatures, which could result in serious damage if said components repeatedly freeze and thaw out.
Although a mesh cover allows air to flow through the AC unit and remove moisture-laden air, you're still better off just leaving your AC unit uncovered.
4. Mold and MildewHeavy moisture buildup inside a covered AC unit can also set the stage for mold and mildew growth. While outdoor mold and mildew buildup doesn't pose the same health risk as it does for your indoor air handler, it can still keep your AC unit from operating efficiently the next time it's turned on.
Airflow blockages caused by heavy mold and mildew growth on the condenser coil, for example, can prevent your AC unit from working properly. Keeping your AC unit uncovered not only prevents excess moisture buildup, but it also keeps mold and mildew growth at bay.
Although you'd want to cover your AC unit before a severe weather event such as a hailstorm or blizzard, there's no reason to keep your AC covered throughout the entire winter. Contact Heatcraft Heating & Cooling to learn more about protecting your HVAC system and to get a free estimate.