A soggy air filter may seem benign, but it's a sign your AC unit is in bad shape. A wet air filter can spread foul odors and bacteria through your home's air ducts. Over time, if your air filter stays soggy, it can even corrode your HVAC unit and reduce its lifespan.
Understanding the issues that lead to a wet air filter can help diagnose what's wrong with your air conditioner and allow you to perform the correct maintenance to keep your house cool all year long.
Your Air Conditioner Has A Clogged Filter
The leading cause of a wet filter is a clogged filter. If you don't change your filter regularly, debris builds up onto this and your air conditioner. Once it becomes clogged with dust, airflow becomes drastically reduced, which compromises the efficiency of your air conditioner. As such, with the airflow reduced, moisture can't leave your unit effectively. This excess moisture leads to excess condensation in the unit and a soggy filter.
Moisture is part of the regular function of your air conditioner. However, you should change your air filter every 90 days if your family doesn't have pets or as often as every month if you do have pets.
Clogged filters also lead to another problem in the form of frozen coils. When airflow becomes limited in your air conditioner, it can cause issues with the heat transfer process that allows your air conditioner to function. When that heat transfer process becomes interrupted, it results in condensation clinging to the coils and freezing.
This condensation will continue to freeze in layers until it entirely restricts the airflow of your HVAC unit, often freezing the filters to the unit. When your air conditioner is frozen, you may hear the unit running but feel no cool air. Conversely, when your air conditioner turns off, the frozen coils are allowed to melt, and the water saturates your filters.
If you open up your HVAC and see the coils are frozen, you should turn off your unit and let the coils melt. Once a filter has frozen or has water damage, you should replace it with a fresh filter.
Dust that can't cling to the filter is at risk of clogging the conditioner's drain pan. Once the drain pan is clogged, water can overflow the pan and saturate your air filter. Water may also seep down the unit onto the floor.
To solve a clogged drain pan, clean the drain pan and replace the filter. Then, carefully monitor the situation and make sure the pan is draining while your air conditioner is running.
If you can't get your drain pan to drain normally, or you can't figure out what's causing your soggy air filter, reach out to an HVAC technician for diagnosis. An air conditioning contractor can provide further insight.