Why is My Furnace Clicking?

Furnaces should operate quietly with only a hum or the sound of airflow through the ducts. Thankfully, you don’t get the knocking and hissing that you would from a radiator.

Clicking sounds from a furnace should not be ignored, though. The problem could be in the ducts, signaling heat loss that is wasting your money and fuel. More importantly, clicking furnaces often have a problem with the gas or oil ignition.

As with most furnace repairs, homeowners should let a seasoned pro fix a noisy furnace. We know how to safely clean and repair pilot lights, igniters, and fuel valves so your furnace runs normally and safely. Once we find the culprit, we should also inspect the furnace to make sure nothing else has been damaged.

The Furnace Igniter is Clicking

Most of the calls we get about furnace clicking sounds relate to the igniter (or pilot light in older models) or the fuel source. Leave the troubleshooting to the HVAC professionals. A small error could indeed be deadly if a gas leak or fire occurs.

Here’s what we look for when a furnace makes a clicking sound at the main unit.

  • Dirty or clogged igniter: Just as a gas stove clicks as it fires up, your furnace makes a clicking noise, too. If it continues for a minute or longer, the igniter needs cleaning or repair.
  • No gas or clogged gas valve: When everything else is working fine but no gas is reaching the pilot light, the igniter will click as it tries to spark a flame.
  • Flame sensor problems: Furnaces have a thermocouple flame sensor that acts as a safety mechanism. The thermocouple might be correctly or incorrectly sensing a problem with the flame temperature and shutting off the gas.

Other Clicking Sounds Coming from a Furnace

Furnaces can make all kinds of noises that you might describe as clicking, popping, or knocking. Some other common problems include:

  • Furnace motor clicking: If the furnace makes a clicking sound while it operates normally otherwise, you might be hearing motor bearings or other small parts knocking around.
  • Inducer problems (in oil furnaces): The fan on an inducer might be clogged, dirty, or loose, causing a clicking sound as it whirs.
  • Clicking or popping sound in the ducts: If you hear the noise away from the furnace, at the vents or throughout the house, your ductwork might be loose or cracked.

Inspection & Furnace Repair in St. Louis

Don’t let an annoying furnace noise carry on without making sure that your system is running correctly. Clicking furnaces can be a sign of a dangerous gas or oil problem.

In St. Louis, homeowners and businesses have trusted Metro Heating & Cooling of Fenton, MO for furnace repairs and maintenance for over 25 years. Contact us now to schedule an appointment for heating services at your earliest convenience.