How Do I Know If My Pilot Light Is Out?

We received this question about furnace pilot lights recently from a Chapel Hill resident:

Dear Air Experts,

The other night, I was about to go to bed when I realized it was getting chilly in my house. That’s when I noticed how quiet it was… my furnace wasn’t running! I checked the thermostat and saw that it was on and set to 71 – but the temperature was reading 67. Of course, it was 38 degrees outside and expected to drop down to 27, so I knew I couldn’t just deal with it in the morning. I called my friend Steve, who knows about this stuff, and asked him what I should do. He said I should check to see if my furnace’s pilot light was still lit. I grabbed a flashlight and headed up to the attic. That’s when I realized two things: 1, it’s WAY colder in the attic than in the house, and 2, this was the first time I had ever actually looked at my furnace. I had no idea where the pilot light was or how to see if it was lit. I didn’t even know what it was – I’m ashamed to admit that I was looking for some kind of light bulb. Defeated, I abandoned my quest and called Steve again. After some cajoling, he agreed to come take a look. When he got there, he tromped up to the attic. Soon I heard a woosh, and the furnace started working again! I have no idea what kind of magic he performed. I want to be prepared in the event this happens again, especially because I feel like Steve won’t be answering my calls after 9pm anymore. So please, tell me: How do I know if my pilot light is out?

 – Andy J, Chapel Hill

Thanks for the question, Andy! And please, don’t be ashamed – many homeowners don’t know much about furnaces because it’s simply not their area of expertise. It’s a good idea to familiarize yourself with your furnace’s basic parts and take a look at it every once in a while, but be prepared to call in a trusted HVAC repair company for most malfunctions.

When your furnace does stop working, there are a few easy steps you can take to troubleshoot it before you call for help. Checking the status of the pilot light is a good place to start and a very easy fix in the moment. If your pilot light keeps going out, you’ll need to call a professional to determine why. Relighting the pilot light can restore your heating immediately, allowing you to get a good night’s sleep before calling for repair service in the morning. Let’s talk about what to do next time this happens:

What Is the Pilot Light?

Andy’s confusion is understandable; most of the time when we talk about “lights” in machines or appliances, we are discussing light bulbs. The pilot light, however, is an actual old-fashioned flame inside your furnace. This flame is supplied by your gas line and should always be lit. When the temperature in your home falls below the desired level, your thermostat sends a signal to your furnace. Your furnace then releases fuel (gas) into the burner, and the pilot light ignites that gas. So basically your pilot light is responsible for combusting your fuel source, which is how your furnace creates heat. If it goes out, the safety features of your furnace will not allow it to release gas into the burner, meaning that the furnace will not run at all.

How to Tell If the Pilot Light Is Out

When your furnace stops working, how do you know if it’s just a pilot light outage? The only way is to go look at your furnace, like Andy did. Follow the steps below to check your pilot light:

IMPORTANT: If you perceive an overwhelming smell of natural gas, do not go any further. Leave your home and call your utility company’s emergency line to have your gas shut off. Then call a professional HVAC company to investigate.

1. Locate the front cover panel on your furnace. It should be a little door that’s easily visible. Open it.
2. If your pilot light is on, it should be easy to see – your eyes will be drawn to the little flame.
3. If you don’t see a flame, your pilot light is out.
4. If there is a flame, check the color. Pilot lights should always be blue. If it is a strange color, this could indicate that the burner assembly is corroded or dirty and needs to be cleaned. Contact a trusted HVAC company for maintenance services.

How to Relight the Pilot Light in Your Furnace

If you discover that your pilot light is out, relighting it is a relatively simple way to restore your heating immediately. It’s best to look up the manufacturer’s instructions. Some manufacturers print these instructions on a label on the outer surface of the furnace. If you don’t see them, check the unit’s manual. If you don’t have the manual, look for your furnace’s brand name and model number, then check the manufacturer’s website for the manual or instructions to relight the pilot light. Make sure to turn your thermostat all the way down or off before attempting to relight the pilot light.

Most furnaces have a fairly common process. First, you’ll have to locate the actual pilot light, which can be difficult when it’s not lit. Look for a small, curved, open metal tube that is pointing at another metal tube. Again, it’s best to use a diagram provided by a manufacturer to locate all the components. Once you know where the pilot light is, you generally follow these steps:

1. Look for a switch or knob that has 3 settings: On, Pilot, and Off.
2. Turn it to “off,” then wait a few minutes to ensure that all gas has dissipated.
3. When you’re ready to relight it, turn the knob to “pilot.”
4. Hold down the reset button (this can sometimes also be the knob you’ve been turning) while lighting the pilot light with a long match or lighter. After the flame catches, continue to hold down the reset button for a little while (usually 60 seconds).
5. After 60 seconds, release the reset button and observe the pilot light. If it continues to burn, congratulations! Turn the knob to “on.”

Pilot Light Problems

If you attempt to relight your pilot light and it doesn’t stay lit once you release the reset button, you’re going to need professional help to get your furnace working again. If your pilot light burns for a while but then goes out again, this is also a sign that it’s time for maintenance or repairs. But hey, don’t you feel proud that you didn’t have to call for help immediately? Now you can call in the pros knowing that you did all you could do first.

Is your furnace having pilot light problems in Raleigh, NC? Don’t hesitate to contact our HVAC experts at Air Expert for emergency furnace repair or furnace maintenance to get your furnace back to working order.