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How to Replace Your Furnace Filter in Your St. Louis Area Home

replace your furnace filter

Changing your air filter is perhaps the most important maintenance task you can perform on your heating system. When the time comes for you to replace your filter, we want to make sure you do it correctly in order to avoid any problems with your unit. So take a look at the six steps below to learn how to replace a furnace filter the right way in your St. Louis area home.

How to replace a furnace filter: 6 important steps

  1. Turn off the power to your unit. Whenever you’re performing any sort of maintenance on your furnace, it’s best to turn the power off as a safety precaution.
  2. Open your furnace’s door or panel. After you’ve shut off the power to your furnace, you’ll want to access the compartment where your filter is housed. Different furnaces have different types of doors and panels to access the inside of the unit, but most of them will easily pop in and out without any problems.
  3. Find your current air filter. Your current filter will be located in between your cold air return duct and your unit’s blower motor. If you have trouble finding it, simply follow your return air duct down to where it meets with your furnace. When you’ve located it, slide it out of your unit.
  4. Make sure your new filter is the same size. Look at the size of the filter that you’ve pulled out of your furnace and make sure it matches the size of the new filter you’re about to install. It’s OK to install a different type of air filter (pleated instead of fiberglass, for example), but the dimensions should be the same.
  5. Install the new filter in the right direction. When you’re installing your new filter, it’s important that it faces the right direction. The filter will have an arrow on the side of it that points to which direction the air is supposed to flow. That arrow should be pointing away from your cold air return duct and toward your blower motor.
  6. Securely replace the door or panel to your furnace. After you’ve installed your new filter, replace the door or panel to your furnace. Make sure the panel is closed securely, because a loose fitting panel might trigger the safety switch in your furnace and cause it to power off.

If you have any questions about how to replace a furnace filter, or if you’d like a heating system serviced or installed in your home, contact Jerry Kelly, your St. Louis area heating and cooling company.