If you’re reading this, it’s probably not because you heard a few clicking sounds from the furnace when it started up. That sound is normal: it’s the ignition starting on the furnace, and it’s no reason to be alarmed. But the furnace shouldn’t be making clicking noises at other times, or clicking consistently or loudly. This is one of the most common warning signs that a furnace has a malfunction and needs attention from repair pros.
There are several possible sources for these clicking sounds, and this is one reason professionals are always essential for handling repairs. Only trained HVAC experts can accurately diagnose the problem so it can be properly fixed. The list below will give you an idea of what to expect, but please don’t use it to attempt a DIY repair—that can be dangerous!
Trouble with the ignition system
Older furnaces may still have a pilot light to ignite the burners, but newer furnaces use a more effective and energy-efficient electronic ignition system, which creates a spark to light the gas from the burners. If you hear a continually clicking sound and the burners in the furnace aren’t lighting, it may be a faulty igniter. The igniter must energize first before the burners start as a safety precaution, so if the igniter doesn’t energize—and this is where you’ll hear the clicking sound—no gas will flow to the burners.
Failed gas valve
The gas valve is what controls the flow of gas to the burners. When the igniter energizes, it signals the valve to open. If this valve becomes stuck, it will cause the same issue with the igniter clicking over and over again because there won’t be any gas there to ignite.
Bearings in the motors
What if your furnace is coming on and you’re getting heat, but you still hear the clicking sound? In this case, it may be a warning that the bearings in the motors for the inducer or the blower are dirty or wearing down. This requires professional attention to lubricate and clean the bearings or to replace them. If the problem isn’t fixed, it will eventually cause the motor to burn out, which is a much more expensive repair!
Electric problems (aside from the igniter)
People often don’t realize how many electronic components are in a gas furnace. The control board for the furnace handles the operation of the blower, the inducer, the ignition system, the gas valves, the limit switch, and more. Loose wiring, dirty relays, or a worn-down board can result in a clicking noise.
Cracked heat exchanger
If you hear the clicking sound after the blower motor shuts down at the conclusion of a heat cycle, it might warn that the heat exchanger has a crack in it. This is a potentially dangerous situation, since it may allow for combustion gas to leak into the house. Shut down the furnace and call for a technician to investigate the furnace.
You can depend on us for the heating repair in Clayton, NC you need, no matter what is troubling your furnace.
Comfort Master Heating & Air Conditioning, Inc. serves the Triangle Area of North Carolina. Call us for 24/7 heating repairs.