Homeowner Articles 6 Signs you Need to Change Your Clogged AC Filter

Your AC filter is the heart of your home’s HVAC system.

It is responsible for making sure everything in your air conditioner runs smoothly. Without one, you could face not only serious damage to your HVAC system but even serious health problems.

And you know what’s just as bad as not having an air filter? A clogged air filter.

Having a clogged filter can leave you with many of the same health and operational issues as having no air filter: which can mean thousands of dollars in repairs!

Here are some signs that your air filter is clogged (and some helpful tips to fix that clogged air filter!).

Blog Table of Contents

1. Inefficient Heating and Cooling

AC breakdown

Whether you have a full HVAC system or just an air conditioner, you need to have clean AC filters to get the most out of your AC system.

Your air conditioner works by taking in existing air, cooling it, and releasing it back into your home. Unfortunately, it also takes in undesirable substances like dust and pet dander.

Air filters prevent these from getting into your system. However, your HVAC system must work much harder to release air when you have clogged air filters.

This causes reduced air flow and a much less efficient heating or cooling process: If it’s harder to release air, it will take longer to warm or cool your house.

2. Higher Energy Bills

Woman burning US dollars on her energy bill

A less efficient system isn’t only annoying because it takes longer to work. It’s also very bad for your wallet.

Clogged filters will require your system to use more energy to get your home to the desired temperature.

And wherever there’s increased energy consumption, there are higher energy bills: especially if your overworked air blower breaks down.

So if you want to save money on your utility bills, ensure your air filter is clean!

3. Low Indoor Air Quality

light shining through a window in a dusty home

Just as a clogged filter will prevent your blower fans from working properly, it will also cause your blower fans to blow dirty air back into your home.

If there’s too much dust and dirt on your air filter, eventually, it will have nowhere to go but back into your home’s air. As a result, a clogged air filter will give you poor air quality.

Should I be worried?

Yes, because this can be very dangerous.

Low air quality has been linked to short-term health problems like irritation and headaches and also more serious long-term problems like respiratory conditions and heart disease.

If you have any chronic allergies, a clogged filter could also aggravate these.

4. Frozen Evaporator Coils

Frozen Evaporator Coil

Clogged air filters can cause a very important part of your air conditioning system to stop functioning.

Located in your air conditioner, the evaporator coil is responsible for cooling your air. Put simply, it removes the heat from your indoor air, leaving your home cool.

When active, the evaporator coil must always be cooling warm air. However, if too much dust is on the evaporator coil, it will not take in enough air to keep its temperature stable, causing it to freeze.

This is frightening because replacing a cooling coil will most likely cost you more than $1000! So make sure you keep that air filter clean, or your utility bill will punish you.

5. Air Handler Issues

HVAC Air Handler

For those unfamiliar, a handler is not specifically part of your air conditioner or furnace but is normally part of your greater heating or cooling system.

Its job is just to keep the air fresh by moving it in a cycle, like an AC. However, it doesn’t heat or cool the air.

Like your Ductless AC, it also has a filter that needs to be clean. If the filter is clogged, this can limit the unit’s ability to keep air coming and going, which can degrade your indoor air quality.

6. Heating Problems

man standing inside a cold home

Dirty air filters can cause your whole system to have problems. Here are some of the components that could break down due to unclean air filters:

🌞 Furnace Failure

Though your heating and cooling system may be separated, they still function similarly: both use filters to keep out unwanted substances.

With a dirty air filter, your furnace may not be able to start. This could be due to limited airflow or potential damage to your furnace.

Furnace problems can also be caused by blocked air vents, air ducts, or a faulty limit switch. However, many common heating problems are linked to a dirty air filter, so it’s best to check your home air filter first.

🌞 Heat Exchange Problems

In your furnace, a component called the heat exchanger transfers heat out of the furnace through a “forced air system” and into various rooms in your home. You may also find one in your air conditioning system.

Your heat exchanger is sturdy, but it can be damaged by dirty filters. With a dirty air filter, there will not be enough fresh air flow in your furnace, which will cause the heat exchanger to overheat and break down.

This can lead to similar problems as a clogged air conditioning system: high energy consumption, unhealthy air, low efficiency, and of course, high bills.

What Should I Do to Keep My Filter Clean?

HVAC tech changing out a clogged AC filter

To avoid cooling system problems, you should replace dirty filters regularly. Most professionals will suggest that you buy a new filter quarterly or half-yearly.

However, you can extend the life of your filter by vacuuming it every one or two months. This simple maintenance task ensures the circular cycle continues in your HVAC system, saving you a service call.

And the best way to know if it needs to be cleaned? Just look for yourself. If you wouldn’t want to breathe in what’s on it, you should probably change it.

Some Final Thoughts on Clogged Air Filters

AC filters keep your HVAC system working its best. So when they’re clogged, you can expect longer waiting times, lower indoor air quality, and, eventually, system breakdown.

If you’re in Greenville or Spartanburg County and worried about the health of your home, we can provide you with professional assistance in cleaning or replacing your AC filter or any AC maintenance job you might have.

Got other home maintenance problems? Check out our other home improvement articles.

This article was written by Morgan Loch

Owner of Upstate Home Maintenance Services LLC and Local HVAC Guru

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