A furnace needs steady, unrestricted airflow to operate safely and efficiently. The filter’s job is to catch dust, pet dander, pollen, and debris—but once it becomes clogged, airflow drops dramatically.

When airflow is restricted, the heat exchanger gets too hot, and the high limit shuts the system down to prevent damage. The furnace repeatedly turns on and off (short cycling), causing components to wear out faster due to stopping and starting more frequently.

Short cycling leads to higher energy bills, uneven heating, and premature failure of blower motors, heat exchangers, and inducer motors, along with an increased risk of system breakdown during extreme cold.

How Often Should Furnace Filters Be Changed? While “once a month” is a good general rule, the real answer depends on filter type and home conditions.

• 1-inch filters: every 30 days
• 2–4 inch filters: every 60–90 days
• High-efficiency (5-inch) filters: every 6 months (check monthly)

Change filters more often if you have pets, allergies or asthma, construction or remodeling dust, a high-efficiency furnace that runs frequently, or multiple occupants in the home.

Furnace filters generally cost between $2-$60, depending on type and efficiency. By comparison, common repair costs are much higher: $500-$1,500 for a blower motor replacement, $300-$800 for a control board, $2,000-$5,000 for a heat exchanger replacement, and $4,000-$10,000 for a full furnace replacement. Changing filters is one of the cheapest forms of preventive maintenance available to homeowners.

If you have weak airflow from vents and your furnace turns on and off frequently, your filter likely needs to be changed. Other signs include rising utility bills, a burning or dusty smell, or the furnace feels unusually hot.

If you need assistance with your furnace filters, call the experts at Chris Heating & Cooling. A professional technician will get your furnace performing at its best.

Visit ChrisMech.com to schedule an appointment, or call (331) 267-7750.

Chris Heating & Cooling

375 Wegner Dr. West Chicago, Il 60185

and

324 W State St #105, Geneva, IL 60134

Ph: (331) 267-7750

chrismech.com