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Asked by: Gerardo Ulshofer
home and garden indoor environmental qualityHow long do 4 inch furnace filters last?
Last Updated: 14th January, 2020
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Also question is, how often should you change a 4 inch air filter?
A good rule of thumb is to change 1-2 inch filters every three months, 4 inch filters every six months and 5 inch filters every 12 months. Signs your air filter needs changed: The filter is visibly dirty. Certainly if you can't see the material of the filter itself, it should be replaced.
how long is a furnace filter good for? The general rule for filter replacement is once every 3 to 6 months. Thicker filters don't have to be changed as often, such as 6-inch filters, which can last between 9 to 12 months before they need to be replaced. For a loose frame of reference refer to this chart: 1″ Furnace Filter: 1 – 3 Months.
Also to know, are 4 inch or 1 inch furnace filters better?
While a 4-inch-thick filter is more efficient than a 1-inch filter, the right size depends on your furnace. If you measure the filter slot, and it's large enough to accommodate the thicker filter, then you can use it. However, if the slot is less than 4 inches wide, you're stuck with using that thickness.
How often do you change furnace filters?
every 90 days