Many people have to do list with “check my furnace filter” written on it, sometimes it’s there for weeks or months. Because it can be an annoying chore checking and replacing the furnace filter is often ignored. But, this is a chore that will be well worth the time spent doing it in the long run. In this article, we will explain why this is so important, how to do it and how often it should be done. Let’s get started.
Why Check and Replace the Furnace Filter?
Changing an air filter in a furnace is a pretty easy and inexpensive task, and yet it’s vital to protect the performance of your HVAC system between the regularly scheduled servicing visits. The furnace filter will also help to improve the air quality in your home by maintaining airflow throughout the rooms. If the furnace filter is dirty, the airflow will be compromised; this will lower the indoor comfort levels and increase energy consumption. When the filter is clean, dust and dirty levels can be better managed, and this can prevent unnecessary repairs and/or premature component failure. When a furnace has to work harder because the airflow is insufficient, extra strain is placed on the system, it costs more to run, and the performance is poor. So, it’s extremely important to change the air filter in your furnace regularly.
When Should the Furnace Filter be Replaced?
Every furnace manufacturer has a recommended schedule showing when you should change your furnace filter. In most cases, every three months should be the minimum interval between changing the air filter. But, this can vary a great deal depending on how the HVAC system is used and other factors relating to your home, such: smokers, pet dander and people in the home suffering from asthma and/or allergies. Many NATE certified technicians will recommend that the furnace filter is checked every month, especially during the heating season.
A furnace filter will come in different sizes and here is a typical schedule for each size.
- 1″ Air Filter: Every 1 – 3 Months
- 2″ Air Filter: Every 1 – 3 Months
- 3″ Air Filter: Every 6 – 9 Months
- 4″ Air Filter: Every 6 – 9 Months
- 5″ Air Filter: Every 9 – 12 Months
- 6″ Air Filter: Every 9 – 12 Months
This is a rough guide, and it will not suit every home perfectly. It’s a great idea to adopt a habit to check the furnace filter every month to see if it needs to be changed sooner. Take a look at the surface of the furnace filter; if it looks gray and it’s covered in dust and debris, it should be changed now. Some other signs that you need a furnace filter changer are more extended cooling and heating cycles and more dust in your indoor air.
What is Your Furnace Filter Size?
A furnace filter will be available in a variety of sizes, and your heating and cooling system need the correct size to work correctly. If you don’t use the appropriately sized filter you could restrict the airflow and/or contaminants may get into your system to degrade and damage the components.
To find out the furnace filter size, go to the filter cabinet and slide out the old air filter. If you look closely, you may notice that the dimensions (length x width x height) are printed on the filter frame. If the dimensions are not there, check the model number instead and check it online to find the exact dimensions.
Replacement furnace filters can be purchased at most home improvement stores. If you cannot find them there, you may be able to order on in store, or you can easily shop for them online. Certain filter brands even have a recurring shipping option to deliver clean filters to your door when you need to change them.
What MERV Rating Do You Need?
Every furnace filter has a Minimum Efficiency Reporting Value or MERV rating between 1 – 20. This shows the buyer how effective that filter is at removing the various contaminants that can be found in your indoor air. The scale is progressively better, so a filter with a MERV of 8 would not be as effective as a filter with a MERV of 12.
A furnace filter in the MERV 8 – 13 range is recommended for excellent filtration levels in residential home settings. A filter with a rating less than MERV 8 would not do a great job of removing airborne contaminants, such as dust, debris, and common allergens. A furnace filter with a lower MERV rating will be less expensive to buy, but it will need to be changed more often.
A filter with a MERV rating higher than 13 is not designed for a home HVAC system. These higher MERV filters are often used in hospitals, clinics, and laboratories. In fact, they are so effective they could even block your air flowing through them, and this could damage your HVAC equipment.
How Do You Change a Furnace Filter?
Changing most furnace filters is a pretty simple task that many homeowners can do easily without any special training. In most cases, the only real difficulty is in realizing how important changing the filter is and ensuring that it’s a priority. You can change your own furnace filter by following these seven simple steps.
Determine the furnace air filter size (as shown above) and purchase one.
Turn off your system by turning off the power or the breaker.
Open or remove the furnace filter panel located near the bottom of the unit.
Locate the filter; it should be resting on top of a pair of metal supports.
Remove one end of the filter and then gently take it out of the compartment.
Check your new filter; look for an arrow to show you the correct airflow direction and install the filter into the compartment.
Put the furnace filter back on, restore power to the system and you’re done.
Repeat this process every three months at the bare minimum, but it’s better to check and replace your furnace filter every month to get the best performance, efficiency and indoor air quality.