All Florida homes need regular upkeep and maintenance during the year. One of the systems in your home that especially needs regular maintenance is your HVAC system. “HVAC” stands for “Heating Ventilation & Air Conditioning”. We may not use heat for much of the year in Florida, but even your cooling system will use some sort of “Air Handler” that will need regular maintenance. One of the simplest parts of maintaining your HVAC system is to change the filter regularly. This is needed for several reasons and can really spell trouble if the filter is not changed regularly.
So, what is the purpose of a filter?
The filter catches all the dirt and airborne contaminants in the air to keep us healthier right? Well… yes, but that is really just a happy side effect of its real job, despite what most people are led to believe. The real function of the filter in your HVAC system IS to trap airborne contaminants, but not primarily to maintain air quality. The main purpose of catching all that debris is to keep it from going into your system.
How often do I need to change my filter?
This is different from system to system and filter to filter. The home itself can also impact how often you should change your filter. If you go to your local hardware store where the filters are located you will see a wide range of different types, sizes, thicknesses and uses. Changing your filter should be done anywhere from once a month to almost once a year. The filter thickness and manufacturer recommendations will tell you how often it needs to be changed. Here is a very rough guide on how often each type of filter should be changed:
- Filters at 1-2 inches thick should be replaced every 1-3 months.
- Filters at 3-4 inches thick should be replaced every 6-9 months.
- Filters at 5-6 inches thick should be replaced every 9-12 months.

Other variables that can affect how often you should change your filter are:
- The amount of people in the household: More people living in the home generates more debris and contaminates. This means in a large household; the filter should be changed more often.
- Pets: This is a big contributor to the amount of contaminates in the air as well. Pets shed fur and dander and can decrease the life of your filter.
- Indoor Air Quality: If a home already has issues with indoor air quality, the filter will pick up a large amount of contaminates and will not last as long either. If your filter is becoming blocked very quickly, consider having an HVAC specialist add an air purifier.
- Allergies: If there are people in the household who suffer from allergies or asthma, the filter may need to be changed more often to accommodate those more sensitive people. There are also special allergy sensitive filters you can get to help with this even more.
- The frequency of use: In Florida, we tend to run our AC pretty frequently. If you are someone that likes it really cool inside, this could cause the filter to need changing more often as well.
Putting off easy maintenance could lead to big and complicated problems.
When you forget to change the filter in your system for too long, problems can arise pretty quickly. Here are just a few things that happen when the filter is too dirty:
- HVAC System Damage
- There are a large number of mechanical and electronic components inside the HVAC system that can be damaged or blocked when debris settles inside the unit.
- When filters are dirty and blocked, it causes the unit the work harder because the air is not moving properly through the unit. This uses more energy and stresses the unit which can damage or decrease the useful life of the system.
- A blocked filter restricts airflow which can cause the internal temperature inside the unit to rise, causing the system to overheat. This in turn can cause components to fail or become damaged.
- When too many contaminates flow through the system, they can become lodged in the condensate removal components. These could be drain lines, condensate pumps or could even spill into the home. This is a common occurrence in Florida due to the high humidity.
- Poor Personal Comfort & Low Air Quality
- When the filter is blocked the air will not flow through the home properly and can cause difficulty in maintaining the desired temperature consistently through the home.
- A blocked filter cannot trap contaminates as easily and the current contaminates will stay in the air, causing discomfort or allergy flare ups.
Don’t Forget Another Filter Change!
Changing your HVAC filter is a very important maintenance task for you and your system! It’s easy for everyone to forget to change the filter. But you should make it a priority to check your filter once a month to make sure it’s in good shape. If the filter is completely covered with contaminants, it’s time to change your filter.
A few ways to help you remember to check your filter is to mark your calendar for once a month, set a reminder on your phone or link the task of changing your filter with paying your utility bill. Don’t pay the bill until you check the filter!
Do yourself and your HVAC system a favor and remember to change your filter!