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Why Is My Pilot Light Out? Furnace Repair Insight

If your furnace uses a pilot light rather than an electronic ignition system, you need the pilot light to stay on if you want to receive warm air from your furnace. When your pilot light goes out, your system won’t have an ignition source for your furnace’s burners, making it so your furnace can’t produce heat. Since a pilot light is essential to a furnace’s performance, it’s important you know the different reasons why your pilot light might be out and what to do to fix them.

What Is a Pilot Light?

A furnace’s pilot light is a small blue flame located in your furnace’s combustion chamber. This flame ignites the natural gas that’s released through a valve and pumped into your furnace’s burner. By igniting the natural gas, your furnace pilot light allows your furnace to generate heat and spread it through your home.

5 Reasons Your Pilot Light Is Out

If your pilot light is out, you’ll likely want to know why it’s not working and how to fix it. As you look for a fix to an out pilot light, review the top five reasons pilot lights tend to go out below:

1. Dirty Pilot Opening

The flame of your pilot light comes out of a pilot opening. When this opening is dirty, it can cause the flame to wave, become unstable, or go out entirely. Since a dirty or clogged pilot light will make it difficult for your pilot light’s flame to stay on or get hot enough to ignite the gas properly, it’s crucial your pilot opening stays clean and clear of obstructions.

If you have a clogged or dirty pilot opening, an HVAC technician can clean out the opening for you. During their cleaning, they’ll need to shut off your system before they start to ensure safety. After they clean out the opening, your pilot light’s flame should look cone-shaped and blue. 

2. Bent Thermocouple

When your pilot light is on, the flame will reach a copper rod called the thermocouple. This thermocouple is a safety device responsible for sensing the flame and shutting off gas if your pilot light goes out. Sometimes, thermocouples can bend and not be in reach of the flame. The thermocouple’s flame-sensing mechanism will then shut off your furnace to prevent gas from reaching your home. Fortunately, an HVAC technician can usually solve this issue by simply bending the thermocouple back into its proper position.

3. Dirty Thermocouple

Dust or dirt build-up on your thermocouple can cause it to not properly sense the flame. As a result, your furnace will shut off out of safety. An HVAC technician can fix a dirty thermocouple for you by shutting off your furnace’s power, waiting for the furnace to cool off, and then cleaning the thermocouple rod. 

4. Damaged Thermocouple

If your thermocouple is damaged, it won’t detect your furnace’s flame and will cause the pilot light to go out. While a bent or dirty thermocouple can usually be fixed with a quick rebending or cleaning, a damaged thermocouple will usually need to be replaced. Over time, any thermocouple will start to wear down, so it’s often more effective to replace the thermocouple instead of repairing it. When you think your thermocouple is damaged, you can trust an HVAC technician to swap out your old thermocouple with a new one.

5. Cracked Heat Exchanger 

Perhaps one of the most concerning causes of a failed pilot light is a cracked heat exchanger. Cracks in your heat exchanger could release the natural gas that fuels your furnace. Without a steady supply of gas, your pilot light will go out. However, the greater concern here is the implications it can have on your health.  

If left unchecked, a cracked furnace heat exchanger issue can lead to carbon monoxide poisoning as the natural gas leaks into your home. 

If you suspect that your Sacramento furnace may have a gas leak, evacuate your home and call PG&E first (1-800-743-5000). Once they confirm your safety, call the gas leak and repair technicians at Bonney (800-444-0551). 

Your smoke alarms should contain carbon monoxide detectors, which is why it is essential to check them regularly. The US Fire Administration also suggests replacing your smoke detectors every 10 years—even if they still seem to function properly. An HVAC professional can also safeguard you from this issue by catching it early during your annual tune-up

Choose Bonney for Furnace Repair Services in Sacramento

If your pilot light is out and you’re looking for furnace repair services near you in Sacramento, California, Bonney has you covered. Our team of furnace repair technicians can inspect your furnace and repair any pilot light issues to ensure you receive the heat you need all winter long. Alongside our furnace repair services, we also offer furnace tune-ups, where we’ll inspect your system and perform any furnace maintenance it needs to run at its best. We also offer multiple coupons and financing options, meaning you can receive our services while staying within budget.

Learn more about our furnace repair services today. If you have any questions or want to schedule an appointment, please contact us.