There are some do-it-yourself jobs that are very simple. Changing your furnace filter is one of them. Because furnaces are big and expensive, most first-time homeowners assume that anything to do with a furnace should be done by a pro. For some things, that’s the right assumption.
Changing the filter is simple, though. And it’s one of the most important things you can do to prolong the life of your furnace.
Why It’s Important
Your furnace filter keeps all of the dirt and dust out of the air you breathe, and also keeps dust from landing on the coils. All filters are rated on the MERV scale, and that stands for Minimum Efficiency Reporting Value. The numbers range from 1 to 16, with 1 providing the least filtration and 16 providing the most. I wouldn’t recommend using any filter with a rating of 4 or below. They’re the bare minimum, and your furnace deserves better. The higher the rating, the harder your furnace will have to work, but the cleaner the air will be.
Not changing a dirty filter could cause your furnace to get clogged, start a fire, or maybe just shut off. At the very least, it will affect the efficiency of your heating unit. Plus, running a furnace with a dirty filter will get you more dirt in the air.
When to Change it
I change my filter about every three months, but some people change it more often, some less. You can usually tell if it needs replaced by looking at it. If it looks dirty, replace it. I have friends that shine a flashlight behind their furnace filter. If they can’t see light on the other side, they replace it with a new one.
The cost of your filters depends on the MERV rating. Filters rated higher are more expensive, and filters rated lower are cheaper. But in any case, changing the filter when it’s necessary can prolong the life of your furnace. Filters are usually sold in cases of three or four, so you can stay stocked up over time.
Changing the Filter
It’s really as straightforward as it could be:
- Remove or open the door panel of your furnace.
- Locate the filter. It should be in plain sight.
- Slide out the old filter.
- Slide in the new filter. Make sure the airflow arrow on the side of the filter points in the right direction, toward the blower.
Check out How to Change Your Air Filter for more specific instructions.