That high-pitched whistling from your furnace usually means restricted airflow. We explain how to solve this common problem.
The Sound of Struggling Airflow
A whistling furnace is almost always crying out for better airflow. The sound occurs when the blower motor is trying to pull air through a restricted opening, much like blowing air through pursed lips.
Common Causes of Whistling
- Clogged Air Filter: This is the #1 cause. A dirty filter forces the furnace to pull air through tiny gaps, creating a whistle. Change your filter!
- Closed or Blocked Vents: Ensure all supply and return vents are open and unblocked by furniture or rugs.
- Ductwork Leaks: Small holes or gaps in your ductwork can whistle as air escapes under pressure.
When to Call for Help
If changing the filter and opening all vents doesn't stop the whistling, you may have ductwork issues or a problem with the blower motor itself. Our technicians can pinpoint the source of the noise and restore proper airflow.
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