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Air Filter Replacement

Furnace and AC filtersFurnace and AC Filters

Furnace and air conditioner filters are designed to removed airborne pollutants and contaminants from the air - making your indoor space safer.

The filters are also designed to protect your furnace blower motor and air conditioning coils from dirt.

Checking your filters monthly and changing them when necessary will protect your family and your wallet - since you will prevent expensive repairs that come from inadequate air flow to the units.

It is generally recommended to replace your air filter before summer (cooling season) and winter (heating season).  

Simply remove and check the appearance of your air filter. The filter will go from white (new) to light grey, to a darker grey as it gets dirtier and clogged with particles. If your filter is dark grey or black, it definitely needs changing.

Air Filters - How to Measure

Not sure what size to get?
You will need to measure your current air filter to get the right dimensions for the replacement filter. First, measure the filter length (L) and width (W). Next, measure the depth (D) or thickness of the filter.

The actual size dimensions of the filter you will need to order will be L x W x D. Most likely, your dimensions will have some fractions. Many filters are sold by 'Nominal Size'.

This is a size with rounded up numbers (no fractions). For instance, if your filter measures 19.5 x 19.5 x .7 inches, the replacement filter that would fit your needs would be the one with the nominal size 20 x 20 x 1 inches.

Air furnace and AC filter saleHow Often Should You Change Your Home Air Filters?

That depends on the type of filter you have, the type of furnace (air flow) and the home itself. Life expectancy of your air filter can be reduced by conditions inside the home as well as your external environment.

If you are undergoing renovations, have pets, live in a dry, dusty area, etc., you may have to change your filter as often as once per month.

The important thing to note is that the air inside your home can be up to 5x dirtier than the air outside. It is not wise to keep dirty filters in your system when they trap impurities, respiratory irritants, bacteria, germs and odors from your home.

The best way to tell is to remove the filter from the furnace and hold it up to the light. If you can no longer see the light, then the filter is too dirty and needs to be changed. Media air filters cannot be washed and should be replaced should they become wet or damp.

Leaving a dirty filter in too long puts your health at risk and may be shortening the life of your furnace as well.

Regularly changing the filter will help you avoid costly repairs since the lack of airflow through a dirty filter can cause a furnace to overheat. The same holds true for an air conditioner.

Running it with a dirty filter means inadequate airflow, which can cause the coils to freeze up. In general, filters tend to need changing more often in winter - when the heater is running. Alternatively, the blower motor can work just as hard in the summer months to keep the house cool.

Changing Your Furnace Filter

Air filter PrecisionLook for the filter near the blower unit.

If you cannot locate the filter, contact the manufacturer or a HVAC contractor. There may be a box cover or grill holding the filter in place.

Remove the filter and put it in a plastic bag to contain the dirt so you can bring it to your garbage can. Put in the replacement filter with the air flow arrow pointing towards the unit.

It is a good idea to keep records of when you replace your filter. Depending on the season and dust levels in your home, you should check it every 1-2 months.

We recommend ordering multi packs of air filters so you always have some on hand.  You can also take a marker to write your filter model number and the date you changed it on the side of the air cleaner so you can reference it easily.

Find the right furnace filter here at Filters Outpost.

Air Conditioning Filters

Your air conditioner filter is meant to trap dirt, dust, germs and grime in the form of airborne particles. It works similar to the lint trap in your dryer, and it similarly becomes ineffective once it becomes full. Once full or clogged, it will restrict the air flow and your air conditioner will have to work harder, wasting energy.

When left unchanged for too long, the filter will no longer be efficient and will not be able to capture airborne pollutants. You put your family at risk since they will be inhaling the dust and germs the filter can no longer trap. A dirty filter can also lead to problems and expensive repairs with your air conditioning unit.

Depending on the type of filter you have, you may need to change it once, twice or up to 4 times a year. It is always a good idea to change your air conditioning filter in the spring - before the warmest weather comes and your unit has to work the hardest.

Get Filtrete, Honeywell, Aprilaire, Nordic Pure and other top name brand filters at online discount prices through Filters Outpost USA.