Top 6 Reasons Your Furnace is Making a Clicking Noise

With some heating appliances, you simply grow used to the noise. There are hums, whooshes, and even gentle hisses—it’s the kind of ambiance you become comfortable around. Noises like these can be typical of heating systems like furnaces, but what if you hear a constant clicking noise?

If your furnace is making a clicking noise, this is a sign of an issue occurring during the heating cycle. When you hear clicking from your furnace, you should contact an HVAC professional immediately, as this strange sound may indicate a faulty igniter or gas valve. Issues with these parts can result in a gas leak.

Why is My Furnace Making a Clicking Noise?

If you’re hearing a furnace clicking sound, then a faulty ignitor or gas valve could be the cause, but those aren’t the only possible sources. Other possibilities include:

• Faulty/dirty flame sensor: A flame sensor detects whether the gas inside your furnace is lit. If the gas is lit, the sensor tells the gas valve to open. If the flame sensor is defective or dirty, it can’t tell the valve to open, making the ignitor click.
• Broken fan blade: A broken fan blade can result in clicking noises from your furnace’s fan or inducer, but those parts can also click from a buildup of debris.
• Worn-out electrical components: If you have an electric furnace, clicking doesn’t indicate a gas leak. However, clicking in an electric furnace likely means that some of its electrical components need repair.
• Cold ignitor flame: The flame inside your furnace may be running too cool to burn gas or oil. If this occurs, the ignition will make a clicking sound.
• Clicking from an air duct: There is a chance that your furnace isn’t the culprit. If you hear clicking noises away from your furnace, they may be sourced from an item rattling around in your ducts.

Top Furnace Issues Associated With Clicking Noises

Let’s dive deeper into some reasons why your furnace is making a clicking noise, along with how to discern one issue from another. Just about all of these issues require the assistance of a trained technician, as they can either be dangerous or difficult fixes to make on your own.

1. Defective Electric Igniter

Most new furnaces use some kind of electronic ignition, honing electricity and gas to heat your home. Whenever you start a furnace with an electric igniter, electricity is used to ignite the flowing gas, but the igniter can be worn out over time.

A worn-out igniter can periodically fail, and if it keeps trying to light the gas, your furnace will make a clicking sound. The noise may last until the flame ignites or the gas valve closes. This failure and its corresponding clicking noise can also result from the igniter’s wiring coming undone.

2. Dirty Flame Sensor

As mentioned previously, a flame sensor detects whether the gas inside your furnace is lit. If the gas is lit, the sensor tells the gas valve to open. The sensor should then signal the igniter to make a spark. When the gas ignites, but the sensor doesn’t detect the flame, the igniter will unsuccessfully try to make a spark, resulting in clicking noises.

The gas valve will automatically close, and the furnace will shut off if the flame isn’t detected. If your furnace isn’t regularly maintained and cleaned, dirt and other debris may begin to cover its flame sensor. When covered, the sensor becomes oblivious to heat. Thankfully, this is a relatively easy issue to avoid. If your furnace is professionally inspected each year, as is recommended, you won’t need to worry about a dirty flame sensor.

3. Gas Supply Problems

If your gas supply is interrupted, clicking noises are a common side effect. You may experience gas supply issues if your gas line becomes clogged or if the main gas supply entirely cuts out. A defective gas valve can also lead to gas supply problems. If there is no gas flow when you start your furnace, the igniter will make a clicking noise until you shut off your heat.

If your furnace refuses to start, be sure to listen for the flow of gas. If you don’t hear anything, try starting your water heater. If your water heater starts, you will want to have your furnace and its gas supply professionally inspected. If your water heater does not work, there could be a larger issue with your gas, and you should contact a certified professional immediately.

4. Malfunctioning Start Capacitor

A start capacitor supplies the energy needed for the fan in your furnace to start. When a start capacitor becomes too fatigued, it can’t supply enough energy to start the fan and instead makes a clicking sound.

When a furnace starts making a clicking noise due to a defective start capacitor, the issue is a straightforward fix for a skilled professional. To avoid a gas leak or other issues, do not attempt to fix this component in your heating system without a licensed HVAC technician.

Read More: Why is My Heat Pump Turning On and Off?

5. Old Fan Bearings

Bearings are essential components of a furnace’s direct-drive motor, which uses those bearings to help the blower fan spin. If bearings become worn out, the fan usually hums loudly while attempting to start.

The first sign of deteriorating bearings will be a clicking or squealing noise sourced from the fan. If your fan bearings are fully worn out or are in the process of wearing out, a technician will need to replace them. It is important to fix bearings, as broken bearings can cause further damage to the blower motor itself, leading to higher replacement costs.

6. Damaged Fan Blades

If your HVAC system isn’t regularly maintained, debris can make fan blades grind against other nearby parts, eventually causing the blades to break off. A broken fan blade will likely make a racket while the fan is running.

Professional Furnace Repair and Replacement Services in Southeast Michigan

If you live in Metro Detroit, you understand the importance of having a working furnace during the winter months in Michigan. A broken furnace puts you at the mercy of 10 and 20-degree days, so if your furnace is making a clicking sound, it is important to contact the HVAC professionals at Randazzo as soon as possible.

Our professionals offer reputable HVAC services in Sterling Heights, Michigan and other areas. We offer all sorts of services, from yearly furnace maintenance to emergency furnace repairs, and as top-rated experts in the industry, we offer free estimates, personalized service, excellent financing options, and regular promotions.

Regardless of whether you need routine furnace maintenance or a full furnace installation, we will be there for you. Don’t hold off: contact our team online or dial 586-336-1111 to make sure your family stays warm this winter.