When your furnace pilot light keeps going out, it’s frustrating—especially on a chilly night. At C&R Services, we see this all the time, and the truth is, that tiny flame does a lot more work than most people realize. It’s the heart of your furnace, the spark that keeps the whole system alive. When it won’t stay lit, your furnace can’t do its job—and your house gets cold fast.
After fixing countless furnaces with this issue, I can tell you most pilot light problems trace back to a few common culprits. Here’s what to check—and when to call for help.
What the Furnace Pilot Light Actually Does
Think of the furnace pilot light as the ignition switch for your heating system. When your thermostat calls for heat, that flame lights the burners and kicks things into motion. Without it, there’s no fire—no heat.
Older furnaces use a standing pilot light that burns continuously. Newer systems rely on electronic ignition, which sparks only when needed. Both can fail, but for slightly different reasons. (Sometimes all it takes is a quick relight. It’s an easy fix that catches a lot of people off guard.)
Common Reasons the Furnace Pilot Light Keeps Going Out
You don’t need to be a technician to notice the symptoms, but knowing the “why” can help you avoid a bigger repair down the line.
1. Dust and Debris in the Pilot Orifice
When the orifice clogs with dust or lint, the flame weakens and flickers out. I once found a pilot completely blocked by a spiderweb—no joke. A quick cleaning fixed it. Still, if you’re unsure, have a pro handle it. Working around gas requires steady hands and the right tools.
2. Bad Thermocouple
That thin metal sensor beside the flame? It’s called a thermocouple. It’s basically the furnace’s safety guard—it shuts the gas off if the flame goes out. But when it gets dirty or fails, it can “think” there’s no flame even when there is. Replacing it is quick and inexpensive, and we do it all the time here at C&R Services.
3. Drafts and Venting Problems
A strong draft or poor vent seal can blow the flame right out. I’ve seen it happen from something as simple as a door opening too close to the furnace. Sometimes, the vent pipe isn’t sealed properly, letting cold air rush back inside.
4. Gas Flow Issues
If the flame won’t stay lit no matter what, you might be dealing with low gas pressure or a partially closed valve. Sometimes the issue goes beyond the pilot assembly itself. If the internal gas valve isn’t opening or regulating fuel correctly, the flame can go out repeatedly. If you want a simple explanation of how that part works, we have a breakdown that covers the role of the gas valve on a furnace and the warning signs to watch for. That’s not a DIY job—your gas company or an HVAC technician should check that.
How to Relight a Furnace Pilot Light Safely
If you’re comfortable and your system uses a manual pilot, you can try relighting it yourself. Here’s how:
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Turn the gas control to “Off” and wait a few minutes to clear any gas.
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Find the pilot assembly and turn the knob to “Pilot.”
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Press and hold the knob while lighting the flame with a match or lighter.
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Keep holding the knob for 30 seconds after the flame appears, then release.
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Turn the knob to “On.” The burners should ignite.
If the furnace pilot light goes out again right after, stop trying to relight it. That’s your system telling you it needs service.
Sometimes, the pilot isn’t the only reason a furnace won’t start. If your system still refuses to kick on, check out our post on what to do when your furnace isn’t turning on — it covers other common ignition and safety switch issues you can look for before calling a pro.
When to Call a Professional
Here’s my personal rule: if you’ve relit the pilot twice in one day and it still won’t hold, call in help. It could be a failing thermocouple, a dirty orifice, or something more serious like a gas control valve issue.
At C&R Services, we use gas analyzers and thermal sensors to test ignition systems precisely. Whether the issue is mechanical or airflow-related, we’ll get your heat back safely and efficiently. And yes, we’ve worked on everything from vintage gas furnaces to modern two-stage units—so we’ve seen it all.
If your system still kicks on but only blows cool air, the problem might go beyond the pilot itself. Sometimes, the burners light briefly and shut off, or the flame sensor fails to confirm ignition. For a deeper look at that issue, read our guide on why your heater might be blowing cold air — it breaks down other causes beyond the pilot light itself.
Keeping Your Pilot Light Burning Bright
Preventing future problems doesn’t take much. Here’s what I tell every homeowner:
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Schedule a yearly tune-up before winter.
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Replace your air filter regularly—restricted airflow affects combustion.
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Seal nearby drafts that can blow out the flame.
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Have a pro clean the burner and pilot assembly once a year.
For deeper reading, the U.S. Department of Energy has a solid overview of furnace maintenance and safety. For seasonal prep, check out The Old Farmer’s Almanac winter forecast to see when colder weather might hit your area.
Should You Consider a Furnace Upgrade?
If your furnace is more than 20 years old and the furnace pilot light keeps acting up, it might be time to think about replacement. Modern systems use electronic ignition, saving energy and avoiding the old pilot flame altogether. We’ve replaced plenty of units in East Texas that were running on borrowed time—and the efficiency gains are no joke.
Contact C&R Services
If your furnace pilot light won’t stay lit, don’t wait until you’re freezing. C&R Services offers prompt, professional heating repair and maintenance services across Tyler and East Texas.
Contact us today to schedule your service or ask about furnace tune-ups before the next cold front hits.
FAQs About Furnace Pilot Lights
Over the years, we’ve noticed a few questions come up again and again. Here are the ones we hear most often.
Usually, it’s a dirty pilot orifice or a bad thermocouple. A professional can clean or replace those parts safely.
It is—if you follow instructions carefully and ventilate the area first. If it still won’t stay lit, call a pro to check for gas or airflow issues.
At least once each heating season, ideally before the cold weather sets in. Early maintenance prevents most midwinter surprises. Why does my furnace pilot light keep going out after I relight it?
Is it safe to relight the pilot myself?
How often should I check my furnace pilot light?
At C&R Services, we take heating safety seriously. Whether it’s a flickering flame or a full furnace replacement, our team’s here to keep your home comfortable—and your pilot light burning bright.
