Brought to you by the professionals at Southport Home Services

We are reaching the end of the cooling season and soon we will be firing up our furnaces. Do thoughts like these remind you to think about if you changed your furnace filter recently? No? Here at Southport Home Services, we have thoughts like these all the time. That is why we bring you this article today to touch on the important topic of changing your air filter regularly. Changing your air filter regularly can lengthen the life of your furnace, help it run as efficiently as possible, and keep the air you breathe at home as clean as possible.

How can an old furnace filter affect the life of my furnace you ask? An older filter can over time develop imperfections and flaws. These flaws can allow dirt, dust, hair, bacteria, etc. to slip through the filter and reach the inner workings of the furnace. There are moving parts to a furnace and when these parts start to get bogged down by dirt and dust, they start to wear down faster. Excess hair can also wrap around moving parts causing wear. Increased efficiency is also a plus to regularly changing out your filter. An old and dirty air filter can wear down on old parts, like mentioned above, but can also affect airflow. A furnace filter can sometimes become so dirty that it will actually prevent the necessary amount of air from reaching the furnace. This can either cause the furnace to shut off or run quite inefficiently, costing you more money. Finally, without an air purification system, that filter is your defense to avoiding spreading germs, decreasing allergies, and overall increasing air purity.

Now that we have an overview of why it is important to change your furnace filter regularly, let’s get to the main event here: When should I change my furnace filter? It Depends. After already reading this far the last thing you want to hear is an ambiguous answer. It is very true that it depends, but we have some information that can help narrow it down and give you a starting point for when you should replace your filter. The main points you will want to look at is pets/animals, occupants, and if you are a smoker.

To start off with, the more pets or animals you have will increase the number of times you will need to change your filter. If your house has two or more pets in it than odds are a MERV 8 filter will have to be replaced around every one to three months. If you have no pets inside your home, then filter replacement for a MERV 8 filter may be closer to ever six months to a year.

What does MERV 8 mean? Learn more about filters by reading our Filter Reference Guide.

Next, the number of people that live in your home can also affect when you need to change your filter. Hair, dandruff, dead skin cells, etc. are all caught by your air filter to keep the air clean. This means that the more people there are to give off these filter cloggers, the more often you will have to change your filter.

Finally, smoking inside your house can also lead to having to change your filter more often. The smoke is brought through the return ducts to your furnace and can actually start degrading the furnace filter. Smoking outside can help lengthen the life of your filter, but if you do smoke inside remember to take that into account.

Looking at factors such as the three we mentioned today are how to figure out when to replace your furnace filter. For instance, if you have two dogs, three people live in your home, and one of you smokes inside, it is most likely a good idea to replace a MERV 8 filter monthly. If you have one pet, two people living in your home, and no smokers a MERV 8 filter may need to be replaced only about every three to six months. Finally, if you have no pets, live alone, and do not smoke a MERV 8 filter may need to only be replaced once a year. Each situation is different and will affect a filter differently. Once you have assessed your living situation, you can then create a starting point for yourself and track how dirty it gets throughout time.

PRO TIP: Write the date of installation on the side frame of the filter in order to remember when you replaced it last.

If you have any questions we at Southport Home Services are here to help. Visit our website for more resources like our Filter Reference Guide or to schedule an appointment for a professional to take a look at your furnace and your filter.

Meet the Author
Thomas Suchla
Thomas Suchla


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