How Can I Tell That My Filter Needs to be Changed?
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Signs your furnace filter needs changing:
- The filter is noticeably gray in color, and you can see dirt and dust built up on the filter media.
- Your home is dustier than usual.
- Your heating or cooling system is cycling longer than it usually does.
- Your current filter has been in use longer than the manufacturer’s recommendation (anywhere from one to six months, depending on your filter).
Why Change Your Furnace Filter
The furnace filter is a key player in home comfort and indoor air quality. Changing your furnace filter regularly offers the following benefits for homeowners:
- Better system performance: The furnace filter is an integral component of your heating and cooling system. When the furnace filter is dirty and clogged with contaminants, air cannot circulate properly through the system. Your equipment will work harder to move air, stressing the system. This can cause breakdowns and overheating. A clean, regularly changed air filter allows air to move properly through your system and keeps out contaminants, keeping your equipment healthier.
- Better comfort: If a clogged air filter doesn’t allow air to circulate through your HVAC system properly, it is also restricted from entering your home. A dirty air filter can limit the amount of conditioned air moving into your home, causing discomfort.
- Better energy efficiency: A dirty furnace filter burdens your system in the ways mentioned above. Components are working harder, meaning they are drawing more energy to do the work – with a clean air filter, less energy is consumed, making your heating and cooling systems more efficient.
- Better indoor air quality: Your furnace filter removes airborne contaminants, pulling them from the air before it circulates back to your living areas. If your filter is dirty, it will be unable to capture contaminants properly, so more will be left in the air you breathe. Airborne contaminants can cause health and allergy issues, as well as make your home appear dirtier.
How Often Do I Need to Change My Furnace Filter?
The frequency of filter changes needed will depend on the recommendation of the filter’s manufacturer, its efficiency, your HVAC system use, and characteristics of your household.
- Filters with low MERV ratings will need changing more frequently than high-efficiency filters.
- Check your filter’s packaging to see how often the manufacturer recommends replacing the filter with a new one.
- Furnace filters typically require more frequent changing during periods where your HVAC system is in use more often. During the peak of summer and middle of winter, your air conditioner and furnace are running more than they are during spring and fall, so more air is passing through the filter and more contaminants are being removed. It’s smart practice to check your filter monthly during periods of high system use, and replace it as you notice buildup.
- If there are pets or smokers in your household, your filter will likely require more frequent changes. There are more contaminants in your home – pet hair, pet dander, and smoking byproducts – so filters become clogged at a faster rate than a home without pets or smokers.