Why Won’t My Furnace Pilot Light Stay Lit?

Having trouble with your pilot light’s flame burning out? There are a wide array of issues that may be causing this. Some are very easy to resolve and others are more complex and might require professional help.

In this article, we’ll go over simple troubleshooting you can try on your own. Then, we’ll explore more complex issues that a professional can help you with:

  • Simple solutions first
  • Your thermocouple is bad
  • Your pilot light orifice is dirty
  • Your gas valve needs attention
  • Your gas regulator is faulty

Want a furnace repair ASAP? You can always count on Four Seasons. Our NATE-certified technicians resolve furnace pilot light issues across Portland and we offer a 100% satisfaction guarantee.

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Explore Simple Solutions First

Let’s start first by assessing if you can quickly resolve your pilot light issue with basic troubleshooting.

  1. Adjust your thermostat. Ensure that your thermostat is set to HEAT and ON because your furnace will simply not turn on if your thermostat is set to COOL. Another simple fix is to replace your batteries if the thermostat display is off or unresponsive.
  2. Replace your air filter. If your air filter is dirty, it can block your furnace’s airflow and potentially cause your exchanger to overheat. Replace your dirty air filter with a new one to resolve this issue.
  3. Check your circuit breaker. If your furnace’s circuit breaker has tripped, your furnace will lose power. You’ll want to reset the circuit breaker. However, if your circuit breaker trips again, do NOT reset it, it’s time to get professional help for safety reasons

Ensure your gas valve is on. Check that your gas valve is set to ON.

If these simple fixes have not resolved the problem, here are some ways professional HVAC technicians can help resolve your pilot light issues.

Your Thermocouple Is Bad

Your thermocouple, also known as a “flame sensor,” is the copper tube that’s located next to your pilot light. A furnace’s thermocouple works to determine when to shut off the gas that flows into your system. Your thermocouple is a critical safety feature and will prevent gas from reaching the combustion chamber if it does not sense the pilot light’s flame.

So, if your thermocouple is dirty, broken or not properly aligned, it may fail to sense the pilot light’s flame and shut off your furnace’s gas flow when needed.

The fix: If your thermocouple is to blame, a technician can repair it or replace it.

Your Pilot Light Orifice is Dirty

The gas powering your pilot light flows through a pilot light orifice. If this orifice becomes clogged with dirt, your flame may weaken to the point that your thermocouple can no longer sense it. When pilot lights begin burning a weak yellow color instead of a strong blue color, a dirty pilot light orifice is often to blame.

The fix: It requires professional skills to thoroughly disassemble a furnace so the pilot light orifice can be cleaned, so be sure to work with a service pro. The orifice should be cleaned at least once a quarter to remove any soot or oxidation buildup.

Your Gas Valve Needs Attention

The gas valve on your furnace delivers the gas your pilot light needs to remain lit. If the valve is turned ON, but your pilot light won’t stay lit, the problem might be a broken gas valve. The solution most likely will be to replace the valve.

The fix: Reach out to professionals to diagnose and possibly replace your gas valve.

Your Gas Regulator is Faulty

Your gas regulator works to decrease the pressure of the natural gas that’s provided to your home. You can typically find the regulator at your gas meter. If the regulator is old or faulty, the gas may not flow through it at a steady enough pressure to support your furnace’s pilot light.

If your gas regulator is faulty, you’ll also notice pilot light problems on your other gas-powered appliances, like your stove or water heater.

The fix: A technician can safely resolve this issue if it’s the source of your pilot light problem


If you’re ready to take the next steps, contact Four Seasons.

Schedule with Four Seasons to repair your furnace! Our NATE-certified technicians are here to help. We offer upfront pricing and a 100% satisfaction guarantee for your peace of mind.

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