HVAC

Change the HVAC filter every three months.

A dirty filter makes the system work harder, pushes dust through the house, and is one of the easiest home jobs to forget. Home Shield lists this as a quarterly task.

Why quarterly is the default

Most 1-inch filters are spent after about 90 days of normal use. Leave one in too long and airflow drops. The blower runs longer. Coils get dirty. In summer you feel it as weak cooling; in winter as dusty air.

Change more often if you have pets, allergies, renovation dust, or a house that runs the system most of the day. A 4- or 5-inch media filter can stretch longer. If the filter looks gray before the 90-day mark, replace it then.

What to buy

Match the size printed on the old filter’s frame. It is usually something like 16x25x1. Do not force a near-size. A gap around the edge dumps unfiltered air past the media.

• MERV 8–11 is fine for basic dust in many systems.
• MERV 13 catches more fine particles. Home Shield’s built-in note points here if your equipment can handle the extra resistance.
• If a high-MERV filter makes rooms feel starved for air, step down a rating or ask an HVAC tech. The furnace or air handler has a limit.

Buy a small stack so you are not hunting for a filter on the day it is due. Product links live in the app’s Buy Now action, not on this site.

How to do it

1. Turn the system off at the thermostat.
2. Open the filter slot at the return, air handler, or furnace.
3. Slide the old filter out. Note the airflow arrow.
4. Put the new one in with the arrow pointing toward the equipment, away from the return grille.
5. Close the door fully. Turn the system back on.

Write the install month on the new frame with a marker. Then you can see at a glance whether it is still current.

The rest of HVAC in Home Shield

Filters are the quarterly job. The app also tracks clean vents once a year and a professional HVAC equipment inspection once a year. See the full schedule.