Answer
How often should I change my AC filter in Louisiana humidity?
The short answer
Check a one-inch AC filter every month in Louisiana and change it as soon as it looks gray. Albers Air Conditioning puts the interval at one to three months depending on use, filter type, pets and allergies. A cooling season that runs most of the year pushes most Northshore homes toward the short end of that range.
Why does Louisiana humidity shorten the filter interval?
Humidity does not clog a filter by itself. Run time does, and in Louisiana the air conditioner runs for most of the year, so far more air passes through the filter between changes than it would in a climate with a real winter. A filter rated for three months by its maker is rated for average use, and a Northshore summer is not average use.
The humidity adds a second problem. Albers Air Conditioning’s own humidity guidance says a dirty filter restricts airflow and reduces the system’s ability to remove moisture from the air, so a filter left too long makes the house feel clammy before it makes the house feel warm. A filter that gets damp and sits can also start to smell, and that smell goes through every vent in the house.
Does the filter type change how often I replace it?
Yes, more than anything else. A one-inch fiberglass filter is the thin, see-through kind and its makers generally rate it for about a month. A one-inch pleated filter is usually rated by its maker for one to three months. A thick media filter, the four or five inch kind that sits in its own cabinet, is generally rated for six months to a year because it has far more surface area to load up.
Those are maker ratings for ordinary conditions. In a house on the Northshore with the system running from April into October, treat them as the longest you should wait, not the normal interval. Albers Air says the same on its filter replacement page: one to three months, shorter with pets or allergies, and the site’s winter advice is to inspect filters monthly even in the cold months.
How can I tell the filter is due?
Hold it up to a light. If you cannot see light through it, or it has gone from white to gray, change it. Two other signs come from the system rather than the filter: airflow at the vents has gone weak, or the system struggles to hold the temperature it used to hold. Albers lists both of those on its filter page as signs a new filter may help.
A filter can look clean and still be due if it is thick with pet hair on the side facing the return. Check the upstream face, the one the dust hits first.
What happens if I leave a dirty filter in?
The system works harder for less cooling. Albers Air’s filter page lists the sequence: reduced efficiency, higher energy bills, poorer air quality and, eventually, damage to the equipment. The damage comes from airflow, because a coil that is starved of air gets too cold, frost forms on it, and the ice blocks what little air was still getting through.
That frosted coil is the same symptom a refrigerant leak produces, which is why a technician checks the filter before anything else on a frozen system. The refrigerant leak page explains the leak version. If the filter was the cause, a new filter and a few hours of thawing fix it. If it was not, the filter was hiding the real fault.
Which filter size and rating should I buy?
The size is printed on the edge of the old filter or in the system’s manual, and the new one has to match it. A filter that is slightly small lets air go round it, which is the same as having no filter. Albers Air’s filter page says the same about matching the size.
The rating is the harder choice. A filter that catches more also restricts airflow more, and not every system is built to pull air through a dense filter. The site’s winter guidance suggests a high-efficiency filter if someone in the house has allergies, and that is a sensible place to start. If the airflow drops noticeably after you fit a denser filter, the system is telling you it cannot handle that rating, and a technician can say what it can.
Does Albers change filters for me?
Yes, two ways. Filter replacement is listed as a service on the site, and it is part of every tune-up: the AC tune-up described on the site covers a full system inspection, coil cleaning, air filter replacement, refrigerant checks, thermostat calibration and performance testing. The annual membership includes filter replacements along with two tune-ups a year, an indoor air quality check, an annual ductwork inspection and a blower and coil deep cleaning.
Between visits the monthly check is still yours. The page on what an HVAC maintenance plan covers sets out what the plan does and does not do.
Is a filter enough for allergies and musty smells?
Often not, in this climate. A filter catches dust, pollen and pet dander on its way to the coil. It does nothing about moisture, and damp air feeds dust mites and mold, which is where many allergy complaints on the Northshore actually come from. Albers Air’s page on whether you need a whole-home dehumidifier explains the signs: a house that feels clammy at the right temperature, musty odors, condensation on windows.
The site also offers air cleaners and purifiers that go beyond what a standard filter does. A filter, a dehumidifier and an air cleaner each handle a different part of the problem, and the company says filtration and dehumidification are often recommended together.
Questions we get asked
Should I change the filter more often in summer than in winter?
Yes, because the system runs far more hours in summer. The filter loads up with run time, not with the calendar, so a filter that lasted three months over a Louisiana winter may last half that from June to September. Check it monthly in both seasons and let what you see decide.
Can I wash and reuse a filter?
Only if it is sold as washable. Albers Air’s filter page says some filters are reusable and can be cleaned, but most are meant to be replaced. A disposable pleated filter that has been rinsed loses its shape and its ability to trap fine dust, and a washable one has to be fully dry before it goes back in or it will grow mold in a Louisiana return.
Does a thicker filter mean I can change it less often?
Usually, yes. A four or five inch media filter holds far more dust than a one-inch filter before airflow drops, which is why its makers rate it in months rather than weeks. It needs a filter cabinet that fits it, so it is a change to make with a technician rather than at the hardware store.
Can a dirty filter make the AC freeze up?
Yes. Blocked airflow makes the indoor coil run colder than it should, moisture in the air freezes onto it, and the ice blocks the remaining airflow. The fix for that cause is a new filter and time to thaw. If the ice returns with a clean filter, call 985-624-8831, because a refrigerant leak produces the same frost and does not fix itself.
Need someone to look at the system?
Call the office and tell us what it is doing. We will tell you whether it needs a visit and what that visit covers.
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