Air Conditioner Filter [Detailed Guide, Issues & Solutions]

An air conditioner cannot efficiently work without an air filter. Since it is crucial to the functionality of the unit, it is important to maintain an air conditioner filter. This article explains various issues with the filter, solutions, and how to change it.

How to Change the Filter in a Central Air Conditioner

Disconnect the air conditioner from electric power and go to the air handler. It is usually at a high point, and you need a way to reach it. Ensure you use a safe and secure method to avoid toppling. Some have the air handler close to the thermostat, so it is easy to remove the filter.

Slide the tabs on the air handler cover to the side to release its locks. The cover will drop down so that you can reach inside it. The filter is right under the cover; it is the component you see once the cover drops down. Carefully remove it, ensuring you catch loose dust particles. The return vents may have dust and dirt; thoroughly clean them using a damp cloth.

Next, take the new filter and insert it in the place of the old one. Check for the position of the arrow on the filter and ensure it faces the return air vents. Inserting the filter the wrong way causes it not to work and may cause problems in the unit. Finally, close the cover and slide the tabs into place to lock them.

When changing the air filter in a central air conditioner, ensure you know the correct measurements. The same applies to all types of air conditioners. The best way to know them is to check the old filter for its dimensions before throwing it out. You can also check the user manual or contact the manufacturer for the correct dimensions.

Air Conditioner Air Filter Dirty – What to Do

If the air filter in your air conditioner is dirty, it is crucial to clean it. And if it has been in use for too long, replace the filter. Turn the air conditioner off and go to the air handler to clean the filter. Some units secure the front grille or panel with screws so that you may need a screwdriver. 

Otherwise, simply pull the cover off and find the air filter. In some cases of window air conditioners, you may not need to remove the grille; slide the filter out by gently pulling the handle. A portable air conditioner has more than one filter, so you must open the front panel and pull out all the filters.

Remove the filter by pulling it out; nothing secures it in place. Next, use a small brush to remove loose dirt and dust particles, leaving it as clean as possible. Place the filter in a sink and run warm water over it if necessary. Pour mild soap over it and gently wash it to remove all the remaining dirt. Rinse the filter to wash off the soap residue, dry it with a cloth, and leave it out to air-dry. Finally, put it back into the air handler.

An air filter must be replaced as often as possible, especially if you live in a dusty place or an area with a lot of construction work. Not all dirty filters need to be cleaned; some require a replacement. Therefore, check the state of the filter when you remove it to determine whether or not it is still usable. If not, replace it. When putting the new filter, ensure the arrow points correctly.

Note: These steps apply to all types of air conditioners. There may be slight differences in the method of removing the filter, but the basics are the same. Follow the instructions in the user manual for the unit to clean the filter correctly.

Air Conditioner Filter Getting Dirty Fast – Quick Fix

It is frustrating to have to clean or replace an air conditioner filter too often. Several factors cause the filter to get dirty too fast; let us discuss them.

A one-inch pleated filter gets dirty faster than other types. The reason is that it easily catches all types of air pollutants, so it quickly fills up. Consider using one with thicker pleats or a disposable fiberglass option. Also, consider an air cleaner to reduce the contaminants in the air.

The second factor is pets in your house or the area of residence. Pets that shed cause the filter to fill up too fast. The same is true if your area of residence sees a lot of construction or has poor air quality. In such a case, use a home air filtration system and the filter in the air conditioner to improve the air quality and reduce the frequency of replacing the filter.

Furthermore, the air ducts may have leaking areas through which contaminated air enters the room. If the ductwork is compromised, the filter will have more pollutants to remove, causing it to fill up faster than usual. Hire an HVAC technician to check the installation and make repairs if necessary.

Additionally, check the fan setting on the thermostat. Typically, the fan should be on Auto instead of On. If you set it to Auto, it cycles off when the compressor does. That way, it does not constantly run. 

However, setting it to On makes it run all the time, even when the compressor cycles off. And if it runs all the time, there will be a steady stream of air, clean or not, to the filter. So, it has to constantly filter the air, causing it to get dirty too fast.

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What Does an Air Conditioner Filter Do?

The job of the filter is to remove dirt and pollutants such as pet hair, dust motes, pollen, and mold from the air. The filter is designed so that it easily catches these pollutants and improves the air quality in the room. The denser the mesh, the better the filter is at cleaning the air. Without it, the air conditioner will release only polluted air and may stop functioning over time due to clogging.

It is crucial to remove and clean the air filter every two weeks. Otherwise, the air conditioner will work harder to release cold air, stressing it and consuming too much energy. A dirt filter also affects other components such as the evaporator and drain line and may eventually stop the unit from working.

You can only wash the filter so much. Some manufacturers recommended replacing it every month instead of cleaning it. However, some air filters do not need constant replacing and can withstand several washes before they wear out. Nevertheless, monitor the filter and replace it within three months of use.

Does an Air Conditioner Filter Smoke?

Not every air filter in an air conditioner can filter smoke. Smoke has tiny particles that many filters cannot catch; only special filters high on the minimum efficiency reporting value (MERV) scale can do it, as this article explains. If you have issues with smoke in your area, ask the air conditioner manufacturer or a trusted HVAC technician to recommend an efficient filter for your air conditioner for filtering smoke.

Air Conditioner Filter Frozen – Quick Fix

Turn off the air conditioner and disconnect it from electric power. Allow the unit to sit for some time to give the filter time to thaw. Alternatively, do not turn the air conditioner off; simply turn off the cooling function and turn on the fan. The air from the fan will slowly thaw the filter because it will not be cold at this point.

While the filter is thawing, monitor the drain pan to catch the water forming from the ice. Most likely, the filter is dirty, so the water will be too messy to leave in the pan. Remove and empty the drain pan to avoid having a pool of dirty water in it and inside the unit. The dirty water can cause further problems with the unit if left unattended.

However, it is crucial to find out why the filter is frozen. The refrigerant is likely too cold, or the compressor runs too often, keeping the temperature at a pretty low point. You must check for possible reasons for the compressor running too often if that is the case or why the refrigerant is too cold. If the filter is frozen, it is probable that other parts around it, such as the evaporator coil, are frozen.

You may need the help of an HVAC technician to determine the cause of the ice accumulation and fix it. And it is always best to fix it before the freezing problem reaches the compressor and other condenser components. If it does, the entire unit may get damaged beyond repair. After fixing the issue, monitor the filter and indoor unit to see if it freezes again.

Air Conditioner Filter Getting Wet – Solved

The air filter in an air conditioner gets wet primarily due to an overflowing condensate drain pan. And the only reason the pan overflows is that the condensate does not flow out through the pipe, which may be clogged with debris. So, check the drain pipe and clear it with a wet/dry vacuum if necessary.

If you do not have access to this type of vacuum, use water and vinegar or bleach for the same purpose. Pour the solution down the drain until all the debris flows from it and the solution is free and clear. Also, empty and clean the drain pan while working on the drainpipe. The filter should stop getting wet after cleaning the drain.

It is possible the filter does not properly sit in the air conditioner and may be falling in the way of the evaporator coil. As a result, the condensate that forms on the cold coil drops on the filter and wets it. Although rare, this issue is a possibility and stems from poor installation. Contact the installation team for corrections.

The risk of a wet filter is that it may clog the system with dirt and cause problems. But regular maintenance checks prevent it from happening because you can clean or replace the filter before it gets excessively dirty. Moreover, high-quality filters keep both small and large particles out of the system, unlike cheap filters that sift only large particles.

Air Conditioner Filter Is Black – What It Means

Turn off the air conditioner and remove the dirty air filter. Throw it out because it is past usage; it is damaged and you cannot clean it. Replace it with a suitable filter but before doing that, clean the area where the filter sits inside the air handler. Ensure there is no residue of dirt before inserting the new filter. If necessary, let a technician service the unit.

There are two possible causes for an air filter that has turned black in an air conditioner. One is soot from constant smoke and two is extreme dirt. Soot from constant smoke in your home may have darkened the filter over time, and it is crucial to reduce the occurrence of smoke for health reasons. But if it is dirt, it is also possible that there is mold growth on the filter.

Air Conditioner Filter Light Blinking – Quick Fix

If you find the filter light blinking on an air conditioner, it may indicate that the filter needs changing. Check the status of the filter and clean it if it is necessary. Otherwise, replace the filter and reset the indicator. Each air conditioner brand may have different methods of resetting the filter indicator.

Some air conditioners have reset filter light buttons, so you can press them to turn off the light. Other units may require you to press the Sleep button and hold it for about three seconds to turn off the light. A few models reset the light when you press the fan speed or fan button and hold it down until the light turns off.

However, several factors can cause the light to keep blinking even after resetting it. Sometimes, there is an electrical issue that disconnects the light from the controls. That way, the reset process does not work anymore. Hire a technician to check the issue and fix it.

Another factor to check is the filter installation. You may have wrongly placed the filter, with the arrow facing the wrong direction. If you recently replaced the filter and have issues with the light, check the position of the filter. Remove it and follow the direction of the arrow to reinsert it.

If that does not work, the air circulation may be poor. If the air passing through the filter is insufficient or restricted, the filter light may start blinking to alert you. Other possible problems are a dirty condenser, insufficient refrigerant, or a malfunctioning compressor. An HVAC technician should check the unit to find possible causes and fix them.

Air Conditioner Filter Never Gets Dirty – What It Means

A dirty air filter may not be ideal, but it is one way to determine whether or not the air conditioner is working. So, if it is not gathering dirt, something may be wrong. You must determine whether or not it is a recent issue or it has been like that ever since you started using the air conditioner. The air quality may be excellent, but the filter must gather some dirt after a few weeks.

Incorrect installation can lead to the filter not sifting dirt from the air. If you installed it yourself, you may have to remove it and try fixing it so that it snugly fits this time. Follow instructions in the user manual or online videos to make a proper fit. 

Another possible cause is your usage of the unit and your home’s setup. If you have a lot of foot traffic and pets, the filter must get dirty. But if you do not have pets and the house is relatively free of so much foot traffic, it may take a long time for the filter to get dirty. The same applies if you regularly vacuum and clean the house.

One last possibility is that the air conditioner is no longer working as it should. You may need a professional to check the unit and certify its efficacy. The unit may no longer be strong enough to filter pollutants from the air; the technician can fix faults and get the filter working again.

Why Does My Air Conditioner Have Two Filters?

Portable air conditioners usually have more than one filter. Some have two, while others may have four. If you do not use a portable unit, the air conditioner in use must have more than one vent. The vent is the point through which air enters the air conditioner and leaves the unit to circulate in the room. It coils also be that the air conditioning system uses multiple units.

There are usually slots for air filters. If your air conditioner has more than one slot for a filter, it means the unit needs two filters. Using only one filter will compromise the functionality of the unit. Also, if you use a central air conditioner, it may have more than one vent, and each vent needs its filter to work. The design and type of the air conditioner are what determine how many filters it has. But it is not unusual to find your unit has two filters.

Are Air Conditioner Filters Recyclable?

Air conditioner filters are recyclable, but it takes some process to do that. It is not simple as putting the used filters in a recyclable bin; you have to sort through the varying manufacturing materials. Air conditioner filters are typically made of mesh, plastic, fiberglass, and a few other materials. You cannot mix all the materials in one place.

So, if you want to recycle your air conditioner filter, it is best to buy the recyclable type. You will also have to find a mail-in recycling company to collect the filters for that purpose. It is an excellent way to rid yourself of the used filters without adversely affecting the environment. An air conditioner manufacturer or major distributor may also have ways of recycling used filters, so contact one of them.

Another method to try is using reusable filters instead of disposable ones. These are the filters you can remove every two weeks or one month and wash in warm water and mild soap. These filters usually cost a little more than the disposable ones, but they are worth the extra money in the long run.

Are Air Conditioner Filters Washable?

Air conditioner filters are washable but not all of them are. Washable filters are the reusable types, while the others cannot be used again or washed when they get dirty; you must throw them out. However, washable air filters have a few disadvantages, even though they help keep the environment clean and save you some money long-term.

It takes some time to maintain a washable air filter. While disposable filters require you to remove and throw them out, washable ones need extra care and attention. Also, they do not filter the air as well as most disposable filters. On the MERV scale, they do not rank high, maybe between one and four, which is pretty low. They are just good for large air pollutants, not smaller ones.

Can a Dirty Air Conditioner Filter Cause It Not to Work?

When an air conditioner filter gets too dirty, the air conditioner stops blowing cold air as it should. The little air it produces will not be clean enough for breathing. This poor air quality can lead to allergies, especially if you are already prone to them. A dirty filter can make you sick, to put it in simple terms.

Also, the air conditioner can begin to short-cycle, it may point to a dirty air filter. A restriction in the flow of air, which such a filter can cause, leads to short cycling. The unit will turn on and off within short intervals. The unit has to work extra hard to cool the room because of the shortage of cold air caused by the dirty filter. The AC senses hot spots around the room and turns on too frequently in a bid to cool them.

The constant running of the air conditioner can lead to an increase in electricity bills. Not only that but some components may get damaged in the process and require repairs or replacements. In a worst-case scenario, the air conditioner stops working because of the stress of running too often. It is crucial to replace a dirty filter or wash it if it is the reusable type.

Does an Air Conditioner Filter Air?

An air conditioner cleans the air with the help of an air filter. While the unit’s primary job is to produce and circulate cool air in your home, the filter in it also ensures the air is clean, as this article explains. That is why it is crucial to keep the filter clean at all times.


Keep your air conditioner filter clean by checking it every two weeks. At most, check it every month and clean it if it is reusable. Do the same for disposable ones, only throw them out after using them for one month. If you must extend their usage, it must not exceed three months.

This guide shows you how to clean and replace a filter in your air conditioner. It also explains why some filters are better than others, how to recycle, and why they get dirty. Bear in mind that some filters do not get dirty fast. It may depend on the area you live, usage, and the type of filter. In addition, use the right type of filter; contact the manufacturer or find an authorized dealer. Also, use the air conditioner’s model number to purchase a filter.

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