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How To Know When To Change Your HVAC Air Filters

Air Conditioning Checking And Filter Cleaning

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Your HVAC air filter is just as important as every component of your HVAC system. If you do not have one, simply purchase one from Custom Filters Direct – an HVAC filters supplier; especially if you have any allergies. In this article, we show you how to know when to change your residential HVAC filters.

But first.

What Happens If You Forget to Replace Your Air Filter?

People often have the wrong idea about what an air filter does. It is designed to safeguard the sensitive components of your HVAC system rather than to filter the air you breathe. It’s crucial to note that while high-efficiency filters can filter out microscopic bacterial, mould, and fungal particles, typical MERV 8-11 filters can only block bigger dust, dirt, and hair particles.

Air filters aren’t meant to filter the air indefinitely. They will eventually fill up with dust and filth. Depending on your system, you need either to replace or clean your filter. Paper filters come with cardboard frames and a paper screen and are disposable. Filters with metal frames are more durable and can be cleaned according to manufacturer directions.

Your HVAC air filter will start to fail if you don’t change it. It will be unable to properly filter the air, allowing dust and contaminants to enter the HVAC system. The working parts of an air conditioner, such as fan motors and valves, become clogged with dust. The system is strained because airflow is constrained. To overcome the impediment, the HVAC system will demand additional power. This is how dust reduces the efficiency of the unit and can cause breakdowns.

When To Change Your Residential HVAC Air Filter?

Your residential or commercial air filter will eventually filter all of the air that passes through your HVAC system to heat or cool your home. This is why it’s important to keep your air filters clean and replace them regularly. 

Filters that are dirty or blocked can:

  • Cause faults in HVAC systems and equipment damage.
  • Reduce the amount of airflow in the HVAC system.
  • Not remove particles and toxins as well as they should, allowing them to reappear in your indoor air.
  • Allow contaminants to accumulate in your ductwork.
  • Increase your home’s energy use and utility bills.

At least once a month, air filters and furnace filters should be checked. If they become dirty, replace them with a new, clean air filter. While removing the air filter from the air handler, shine a light on it. you’ll be able to see if it’s dusty or clogged; if you can’t see the light through the filter, it’s time to replace it.

 Air Conditioning Checking And Filter Cleaning

Factors That Influence The Frequency Of An HVAC Air Filter

1. How Frequently Do You Utilize Your HVAC System?

If you live in a mild area and only use your air conditioner or furnace for a few hours each day, one filter could last you a season or even a year. On the other hand, if you use your HVAC system regularly, the filter should be changed every few weeks (especially if you are using fibreglass filters).

2. The Dimensions Of Your Home

If you live in a “smaller home,” your air conditioners and furnaces must pump less air to achieve the same temperature change, which means fewer filter changes. However, because the smaller the appliance used to cool the tiny room usually has smaller filters, you may need to change the filter more frequently than you would in a larger residence.

3. The Quality Of The Air In Your Home

The air outside and within your home influences the replacement cycle of your air filter and furnace filter. You’ll need to replace your air filter more frequently if you have poor air quality outside or pets inside.


Alas, the frequency at which you should change your residential or commercial HVAC air filters depends on the type of home or building you live in or use, the frequency at which you use your air conditioner and if you have any allergies or asthma. Ideally, every HVAC air filter should be changed every three months.