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Why Air Conditioning Filters Are Crucial to Your Unit

July 9, 2015


Like many of our convenient appliances, we sometimes get so used to our air conditioning working the way it’s supposed to that we forget they need the same kind of maintenance as anything else in our home. That is, until it’s 100 degrees and you’re wondering why you can’t seem to cool the house down.

If you don’t stay on top of your AC maintenance, it is highly likely you’ll run into cooling issues in the future. The air filter is one of the most basic, but crucial, pieces of the system, and failure to keep up with basic care can result in costly air conditioner repairs in the future.


What Exactly Is an Air Conditioning Filter, and Where Is It?

Almost every air conditioning system has a filter upstream of the evaporator coil (this can be a fuzzy-looking or folded paper filter) in the return grille or in slots in the duct system. The filter discards particles from the air stream to keep the AC system clean.

As this takes place, the filter becomes loaded with more and more particles, increasing resistance and reducing airflow. This is how you know it’s time to change the filter. The amount of time this takes to happen all depends on how dirty the air is and the size of the filter.

If the filter does not get changed, it causes the airflow to go down and the system will not perform well. Taking the filter out completely solves the low airflow issue, but only for a short time. The particles that would have been taken out by the filter will build up on your evaporator coil and eventually cause it to fail.

The question still remains though, what would happen if you were to run your AC without a filter? Well, there are several different mechanisms that can become damaged while the filter is out:

  • Metal Tubes. Air is blown from your home across metal tubes that are always wet with condensations and contain Freon. Now this is not a problem as long as the air is clean. Unfortunately it is likely that there will be debris in the air, which sticks to the wet tubes, coating the fins and leading to inefficient cooling.
  • Condensate Drain. This serves as a path to let the condensation escape safely. The drain is designed specifically to handle liquids, not solids, so any buildup of dust, hair, and/or other debris will cause it to clog up. Overtime, this will cause the water to back up inside the unit, which can cause the unit to leak or shut down entirely.
  • Duct System. Knowing all of this, it is okay to leave your AC running without a filter for a maximum of 2-3 days depending on the situation, but it’s important to get a replacement as soon as possible. As determined above, running your AC without a filter can not only cause problems with the air conditioning system itself, but can lead to health issues too.

    Air Conditioner Filter Maintenance Tips

  • If your AC uses disposable filters, stock up.
  • Make sure to get your replacement from a factory authorized dealer.
  • Give your reusable filter time to completely air dry after being washed with water.
  • Keep the AC off while the filter is out, and if you absolutely can’t, don’t go more than a couple of days.

Have other questions or concerns? Call Superior Water & Air today!