Can a Dirty Air Conditioner Filter Make You Sick?

Yes! This article explains how dirty air conditioner filters can make you sick.

It also details the sources of these contaminants and what you can do to reduce your risk.

When an air conditioner filter becomes clogged with dirt and debris, it can reduce the air quality in your home.

This can lead to various health problems, including respiratory problems, allergic reactions, and headaches.

It’s essential to regularly clean or replace your air conditioner filter to maintain excellent air quality in your home.

This will help to keep you and your family healthy and prevent potential health problems.

Moreover, the air conditioner filter should be changed every six months, depending on how often you use your AC and how dusty it is in your home.

This article also discusses how regular cleaning can prevent these problems and what you should do if you already suffer from an infection.

What Side Effects Are You Likely to Have From a Dirty AC Filter?

Can a Dirty Air Conditioner Filter Make You Sick

The side effects you are likely to have from a dirty air conditioner filter depend on several factors, including the severity of the contamination and your sensitivity to the microorganisms that may be present in the air.

Some common side effects of a dirty air conditioner filter include respiratory problems, such as coughing, wheezing, and difficulty breathing, as well as allergic reactions, such as sneezing, itchy eyes, and skin irritation.

A dirty air conditioner filter can trigger asthma attacks or severe health issues.

To avoid these side effects, it’s essential to regularly clean and replace your air conditioner filter. The more common health implications are:

  • Frequent or worsened allergies.
  • Common colds and frequent sneezing
  • Sinus infections.
  • Respiratory infection.
  • Watery eyes and runny noses
  • Nausea and occasional dizziness
  • Headaches
  • Skin irritations
  • Shortness of breath and fatigue.

Related Air Conditioner Sounds Like Water Running

How to know if your Air Conditioner Filter is Dirty

If your air conditioner filter is dirty, you may notice a decrease in airflow from the vents, an increase in your energy bills, and a musty smell coming from the unit.

To check the filter, locate it and visually inspect it to see if it is dirty. If it is, you should replace it with a new one.

It’s important to clean or replace your air conditioner filter regularly to maintain the efficiency and performance of your air conditioner.

1. Poor Airflow

How does a dirty AC filter influence airflow? A blocked dirty filter will cause pressure on the air conditioner fan motor, leading to the AC unit’s failure.

If you do not realize the instant change in air flow, you can perform a simple test.

Place your hand in front of the AC filter to check if the airflow is in and out. You should feel a leisurely passage of air and, therefore, no stuffiness.

2. Poor Air Quality

An air filter aims to ensure clean air circulating in your home. The filter will therefore sieve through everything from dust to pollen to debris.

A dirty or clogged air filter will not be able to diligently perform this task, reducing the quality of the air you breathe.

3. High Energy Bills

Most of the time, AC filters work hand in hand with thermostats to ensure the desired temperature in your home.

Once you set a temperature in the thermostat, the filter will work to achieve that goal.

However, a clogged AC filter will overwork to ensure the set temperature is reached.

It will lead to more than the average power consumption displayed on your electricity bill.

4. Inadequate Cooling

Together with ensuring clean air circulation, an AC filter is also responsible for a cool temperature set using the thermostat.

Dirty air conditioning filters will, however, have a more challenging time as the cooling coils in the filter are clogged by debris and dust.

If the clogs are not taken care of as soon as possible, they will form frosts whose further melting will cause irreplaceable damage to your filter.

Additionally, you need to spend more money to replace the filters.

What Does a Dirty Air Filter Look Like?

A dirty air filter can have a variety of appearances depending on how long it has been since it was last cleaned or replaced.

In general, a dirty air filter will have a buildup of dust, debris, and possibly even mold on its surface.

It may appear grey or black, clogged with a thick layer of dirt and other contaminants.

Sometimes, a dirty air filter may even have a musty odor.

If you are unsure whether your air filter is dirty, it’s best to remove it and visually inspect it to see if it needs to be cleaned or replaced.

A dirty air filter indicates that the air conditioner needs to be serviced. It can also signify an excessive amount of dust in the room.

There are two types of filters:

  1. The pre-filter, at the front of the unit, catches large particles like hair and pet dander and some larger particles from the air outside.
  2. The filter behind it catches smaller particles like dust and pollen inside your home.

The filter behind it needs to be changed every three months or so depending on how often you use your AC and how dusty your environment is, but the pre-filter should be checked once a month or so to make sure it’s not too dirty or clogged up with hair and pet dander.

How often should You Clean the Air Filter?

Different types of filters will require varying cleaning methods.

A reusable air conditioning filter will need its owner to clean it thoroughly four times a year, that is, every three months.

Thorough cleaning will ensure you maintain your home’s air quality, preventing allergic reactions.

However, a disposable air conditioning filter will require different maintenance around similar times.

As the name is disposable, this air filter will need replacement with a new one. It ensures maximum efficiency in filtering particles out of your indoor environment.

Most people struggle with cleaning or replacing an Air Conditioning Filter.

It should be no excuse for regular maintenance, as there are experts in this field.

The experts should help you maintain your AC filter and provide preventative options for the air conditioning system through troubleshooting techniques.\

They should be able to check the lubrication levels of parts such as compressor fans and the coolant levels, perform and conclude multi-point inspections, and output baseline.

While shopping for experts, pick a reputable company with certified professionals and good reviews, or ask your friends or families for recommendations.

What Factors Should You Consider When Choosing an Air Filter?

To prevent frequent clogging of filters, you must choose one suitable for your Air Conditioning system.

There are several factors that you should consider when choosing an air filter for your home or business:

  1. Size: Choosing an air filter that is the correct size for your HVAC system is important. An air filter that is too small will not be able to effectively filter the air, while an air filter that is too large can restrict airflow and cause your system to work harder.
  2. MERV rating: The Minimum Efficiency Reporting Value (MERV) rating measures an air filter’s effectiveness at trapping particles. Higher MERV ratings indicate a more effective filter but also a more expensive one.
  3. Type of filter: There are several air filters, including fiberglass, pleated, and washable. Each type has its unique benefits and drawbacks, so it is important to consider your specific needs when choosing a filter.
  4. Cost: Air filters come at various prices, so it is important to consider your budget when choosing one.
  5. Frequency of replacement: Some air filters need to be replaced more frequently than others. Consider the cost and convenience of replacing the filter when making your decision.
  6. Allergies: If you or someone in your household suffers from allergies, you may want to choose a filter with a higher MERV rating to help capture more allergens.
  7. Pet dander: If you have pets, you may choose a filter specifically designed to capture pet dander and other pet-related allergens.
  8. Location: If you live in an area with high levels of dust, pollution, or other contaminants, you may want to choose a filter with a higher MERV rating to help filter these particles out of the air.

Types of Air Conditioning Filters

There are different types of air conditioner filters, and they include:

  1. HEPA Filters. These filters are deemed the most effective filters. They excellently trap the smallest particles in the air. Many of those available in the market are industrial sets for clean rooms such as laboratories, which have no allowance for contamination, with only very few models for residential use.
  2. Permanent reusable filters. These filters are cost-effective as they are easy to clean and last up to five years. They are a lot cheaper than HEPA filters.
  3. Disposable pleated filters. These filters have wrinkles, and their increased surface area allows for excellent air cleaning. They are also inexpensive to purchase and the most preferred by home residents.
  4. Disposable Fiberglass Filters. These filters have a low minimum efficiency reporting value. They are, therefore, only suitable for blocking large particles in the air. They are, however, the most affordable of all filters.

What are MERV Ratings, and How Do They Affect Air Conditioning Filters?

MERV(Minimum Efficiency Reporting Value) is a way industrial experts can identify the level of excellence with which an air filter works.

This score rating goes from one to twenty, with the highest score being twenty and the lowest being one.

The higher the score, the better the ability of the air filter to trap smaller particles out of the indoor environment.

Higher may not always mean better when operating costs are considered.

Filters with higher minimum efficiency reporting values consume much more energy than the lowly scored ones interpreted in your energy bill.

Air filters with high MERV are typically more expensive than the lowly rated ones and are considered worth the deep pocket dive.

It is, however, important to first let an expert evaluate the current air quality of your home to recommend the most appropriate air filter.

The disposable fiberglass filter, for instance, has a shallow minimum efficiency rating value of between one to eight. These numbers indicate that only large particles can be filtered.

Disposable pleated filters have a MERV of between nine to fourteen.

On the other hand, HEPA filters have a MERV ranging between fifteen and sixteen.

How Do You Effectively Clean an Air Conditioning Filter?

Can a Dirty Air Conditioner Filter Make You Sick

You must be extra careful when cleaning your air conditioner filters to avoid damaging them. Here is a step-by-step process.

Method One 

There are a few steps you can follow in cleaning an air conditioning filter effectively:

  1. Turn off the power: Before cleaning the filter, turn off the power to your air conditioning unit to avoid any potential accidents or injuries.
  2. Remove the filter: Most air conditioning filters are in a grill or vent near the air handler or furnace. To remove the filter, locate the grill or vent and gently pull it away from the wall or ceiling.
  3. Vacuum the filter: Use a vacuum cleaner with a hose attachment to remove any visible dirt, dust, or debris from the filter. Be sure to vacuum both sides of the filter to remove as much dirt as possible.
  4. Rinse the filter: If it is particularly dirty, you may want to rinse it with water to remove any remaining dirt or debris. Place the filter in a sink or tub and gently rinse it with warm water.
  5. Dry the filter: After rinsing the filter, let it dry completely before reinserting it into the air conditioning unit. This may take several hours, so it is a good idea to clean the filter in the morning, so it has plenty of time to dry before you need to use the air conditioning later in the day.
  6. Reinsert the filter: Once the filter is dry, slide it back into place in the air conditioning unit. Ensure it is seated properly and all edges are fully seated in the filter frame.
  7. Turn the power back on. Once the filter is in place, turn the power back on to your air conditioning unit to resume normal operation.

It is important to regularly clean or replace your air conditioning filter to ensure that it is functioning properly and that the air you breathe is clean and healthy.

Depending on your filter type and the level of use, you may need to clean or replace it every month or every few months.

Method Two

Items Needed

  • A Hand Vacuum
  • A Clean microfiber cloth
  • A hose
  • White vinegar
  • Warm water


  1. Make sure the Air Conditioning is turned off. It will ensure your safety as you clean, and you will also clean without further accumulation of dirt in the AC and circulation of poor-quality air.
  2. Ensure all vents have their air filters removed. Many Air Conditioning units have many filters which the cleaner could forget. You want to ensure a thorough job is done.
  3. First, you must hand vacuum the air filters to remove allergens and dirt buildup. It will make the next phase of cleaning relatively easier to handle.
  4. After hand vacuuming, clean the frames of the filter with a microfiber cloth.
  5. Time to wash the filter! This task could either require you to use a deep sink to clean your filter from there or a high-pressure hose. You may, however, find it necessary to soak the filters in warm water and white vinegar to help get sticky grime off. This soaking process should take at least thirty minutes.
  6. Rinse with a dry microfiber to dry or air dry. Twenty minutes should be enough time for drying.
  7. Once completely dry, inspect the filter for any previously visible damages. This stage is crucial as you can indirectly extend your Air Conditioner’s lifespan. Check for holes and particles that remain unremoved. You must also remember to check all expiration dates for all filters to replace any expired ones.
  8. Now you can reinstall the filters correctly and test how your AC works!

Related: How To Clean A Window Air Conditioner Without Removing It

Final Thoughts on Can a Dirty Air Conditioner Filter Make You Sick

In a nutshell, A dirty air conditioning filter severely impacts your health. The air conditioner filter is meant to clean the air you breathe, as it traps dust, debris, pollen, and many other unwanted substances.

If your filter is dirty, it cannot perform its task.

Therefore, cleaning it regularly and replacing it when it has outlived its purpose is essential to safeguarding your health.

So, if you are having allergic reactions or a cold and not because of the change in weather, it’s time to look at the condition of your air conditioner filter. There are, however, more ways to note it’s time to clean your filter.

We have learned that it is not just the air conditioner filter that can make you sick but also other areas in your home. The best way to keep yourself safe is by maintaining your home and keeping your filters clean.

Leave a Comment