A filter change sounds like the easiest job in the house. It can be,
until you discover three different return grilles, a filter at the
equipment, and an old box in the closet with the wrong size written on
it. I see the most value in making a little map of what your particular
system actually uses.
Find the right location and
size
Look for the filter at the return grille or in a slot near the air
handler or furnace. Some systems have more than one. Write down the size
printed on the filter and check the fit of the replacement. Air should
pass through the filter rather than around a gap at the edge. Follow the
airflow arrow when you install it, and close the cover or grille
securely.
Put the date on the frame and in your calendar. ENERGY
STAR advises checking the filter monthly and changing it when dirty,
at least every three months for many systems. Pets, renovation dust,
frequent operation, and filter type can change the interval. Your
equipment instructions take priority. A washable filter has a different
cleaning and drying procedure; don’t replace it with a random disposable
filter unless the system permits it.
What the filter cannot fix
A fresh filter will not repair a loose duct, a blocked return, an
iced coil, or a blower problem. If airflow stays weak, the system makes
a new noise, or the filter quickly turns unusually dirty, ask a
qualified HVAC contractor to evaluate the cause. Avoid stacking filters
or choosing a high-resistance product solely for a bigger number on the
package. Compatibility matters.
I keep local
contractor contacts on Helpful Resources if you need HVAC service.
My Homeowner
Tools & Supplies page has filter and other maintenance ideas;
match any purchase to the equipment label first.