What Does a Dirty Furnace Coil Do to Your HVAC System?

Your HVAC system is comprised of many parts designed for specific roles. If one of the parts isn’t working efficiently, such as a furnace coil clogged with debris, you may notice it with higher energy bills, system wear and comfort problems. To avoid these problems and ensure efficient heating through winter’s end, read on to learn if your furnace’s coil is an issue, and what to do about it.

Role of Your Furnace Coil

In Wilmington area homes, HVAC systems often consist of a forced-air furnace for home heating and an A/C unit that shares the furnace blower for home cooling. The cooling portion of the A/C (i.e. the furnace coil — also called an evaporator) is generally nestled between the gas furnace and the blower.

In “cool” mode, warm return airflow is cooled down as it streams through the cold coil, and then it’s redistributed to your home through the supply ducts. During the winter, however, the coil simply sits idly by waiting for warmer weather.

Dealing With a Dirty Furnace Coil

The problem with a dirty coil in regards to home heating is that your furnace and A/C probably share the same blower. While your furnace is busy at work heating return airflow, the blower can struggle to pull the heated air through a clogged coil. This makes the blower work harder and use more electricity.

In addition to dirt, furnace coils are targets for mold and mildew growth. This is due to the vast amounts of condensate that form on the coil, which provide the conditions necessary for mold development. Mold and other contaminants may also spread to the ducts or blow through the living spaces.

The best way to avoid these problems is very simple. Schedule preventive maintenance with your HVAC professional — ideally in the fall and spring, or any time in between.