Can Furnaces Run Without Filters?

heating The short answer is yes, your furnace can run without a filter. But you should NEVER do it. It can damage your heating system and lead to very expensive repairs. It can also lead to higher utility bills.

How Filters Work

Traditional forced-air heaters take in air through return air ducts and warm it up over a heat exchanger. A blower fan forces the air through the ducts in your home as it branches out to different rooms. The furnace filter does exactly what it says. It filters the air to keep dust, hair, and other contaminants from getting to the furnace. This does several things:

  • Keeps contaminants from getting into your heater which can build up and cause damage
  • Prevents contaminants from being recirculated throughout your home
  • Allows your furnace to work efficiently
  • Removes allergens such as dust, pollen, and mold from the air in your home

Using A Dirty Filter Is Bad

A dirty furnace filter can cause all sorts of trouble. If your heater is unable to draw in the air it needs to operate, the blower fan and the furnace can overheat.

Using No Filter Is Really Bad

Operating without a filter altogether can allow debris in the air to pass through the vents and hit the metal components in the furnace. Even microscopic particles can do damage to components. This wear and tear can drastically reduce the life of your furnace.

This dust and debris also can build up in your blower fan. That could jam the motor and cause it to overheat. It can also cling to the blower and act as insulation keeping the heat in when it blocks the vent holes or when it collects in the curved vanes of the blower wheel. Even if your furnace does not overheat, it will limit the air flow.

A hot running blower fan can also damage other parts. When the furnace runs hotter, it’s bad for the heat exchanger as well. It can cause problems for your coils, ignite, and contacts which need to stay clean in order to perform at peak efficiency. In some cases, your furnace might shut down altogether.

Jco Heating and Air Conditioning
If you live in the Springfield, Oregon or surrounding areas, call Jco Heating and Air Conditioning to schedule a service call and make sure your furnace is operating at peak efficiency. We offer heating repair, installation, and maintenance services!