Why Does My Pilot Light Keep Going Out? Ultimate Guide

Learn what makes it going out and how you can fix that

Written by Camilla Moln. Updated on Why Does My Pilot Light Keep Going Out

Have you ever experienced that? You wake up in the morning, and you suddenly realize that it is way too cold in the room! But why? The heater was working yesterday when you went to bed. But now the air in the room is chilly and you feel like you were almost sleeping outdoors!

The very likely reason is that your pilot light went out leaving you cold and frozen under the pile of blankets. But why did it happen? Well, before you rush and call the HVAC professional to come for your rescue, we recommend you try to figure out what might be wrong with your pilot and the furnace. 

Why does my pilot light keep going out on my gas furnace? This is the question we are going to answer, as well as the issue we are going to solve in this article!

Why Does My Furnace Pilot Light Keep Going Out?

Keeping your home warm is important, especially in winter, this is why we all use gas furnaces, for example. However, it happens quite often that your furnace suddenly stops working as it should be, and you are left out with the cold house or apartment right in the middle of the night! You can even give it a try and make attempts to re-light the pilot, and it may even start working again for a while! But then it goes out again.

Why could that happen to your pilot light? Well, there are a few reasons that could lead to such a scenario, but fortunately, none of them can be considered fatal. It may so happen that you don’t even need help from professionals in this case!

In this situation, the best solution will be to stop panicking. Before you call HVAC professionals or start calculating how much an urgent repair will cost to you, we recommend you try and fix this issue on your own. Moreover, it is not an impossible task!

Why Does My Furnace Pilot Light Keep Going Out
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Faulty Thermocouple

If your pilot light does not want to work properly and it keeps going out, it is highly possible that the thermocouple is the culprit. What is that thermocouple? Well, it is a copper rod that the pilot flame hits directly. It can also be referred to as a flame sensor.

Thermocouple is needed since it serves as a safety mechanism that shuts the gas off should the pilot light go out suddenly. And in case the thermocouple fails to shut the gas off, all the gas that is flowing through the furnace could get right into your home! This is why thermocouple safeguards against such a catastrophic gas buildup.

Why can thermocouple work improperly or not work at all? 

  • It is broken or burned out. In this case, it will not detect the flame properly, closing the gas valve until you replace it. 
  • It is dirty. The soot buildup on the thermocouple may block the flame, so even a slight residue can lead to its malfunction.
  • It is not lined up. See, the pilot light flame needs to envelop the top of the thermocouple completely to know the flame is on. If it’s not lined up correctly, it will not read the flame and thus the valve will be shut for the gas.

Fortunately, none of these reasons are fatal! If your thermocouple is broken or burned out, it is very easy to fix that. Replacement will not cost much, besides, if you are mechanically inclined, you will even be able to do that on your own. And in case you are not that confident, you can always call professional furnace repair technicians. Anyway, it will not cost you a fortune.

In case your thermocouple is dirty, you will just have to clean it. Simply remove it, clean it using a wire brush or something coarse, and replace. Such a maintenance is better to be done annually to be sure your furnace is functioning properly.

Faulty Thermocouple
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Pilot Orifice Is Dirty

In case you can manage and keep the pilot light lit for just a little bit, try to inspect the flame. See, if the pilot light is working properly, it will look like a strong blue cone, not a weak yellow flame since a weaker flame will not be able to envelop the thermocouple as it should be.

If it is weak, the pilot light orifice might be dirty. To clean it out, you will have to disassemble the pilot and clean all the debris out with the use of a needle or compressed air. However, if you don’t feel confident enough to start tampering with such important parts of your furnace system, feel free to call the professionals. 

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Bad Gas Regulator

Yes, the problem can nest outside of your home! See, if the gas meter of yours has a bad regulator, it will affect all the gas appliances you have including furnace, dryer, stove, and others. In this case, your furnace may simply not be able to get enough gas for keeping the pilot light lit!

So in case you notice problems with other gas appliances as well, this is most likely the culprit. Contact your utility company instantly to fix it correctly and safely. 

Bad Gas Regulator
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Fluctuating Natural Gas Availability Based On Demand

Well, it may so happen that the problem is not about you or your home gas system. When natural gas consumption peak, the “gas grid” in your area may near its capacity which will lead to lowering of the gas pressure.

In this case, even the slightest hiccup in gas supply to your furnace will be more than enough for making the pilot light to go out! So what we recommend is that you ask your neighbors around whether any of them also has problems with their pilot lights. And if the problem persists, you should get in touch with your utility company. 

Fluctuating Natural Gas Availability Based On Demand
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Improper Air Flow Or a Strong Draft Blows the Pilot Out

Finally, if you see that your pilot light can easily be re-lit after going out overnight, it simply means that it was blown out by a draft. If you tend to have excessively windy days or nights in your area, this can be quite  a common reason. 

So to make sure it stops, you should keep every intake air register in your home open and clear in order to avoid that vacuum effect in the inlet.

So, when you are aware of what can lead to your pilot light tricks, it will be easier for you to figure out what exactly made it go out this time. But if you fail to find the reason on your own, or if the problem appears to be more serious than you expected, call the gas service immediately.

Improper Air Flow Or a Strong Draft Blows the Pilot Out
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What If I Can’t Find the Pilot Light Or Locate the Thermocouple?

Well, we agree, not all of us are knowledgeable about the technical side of the matter. So, if you find it difficult to spot the pilot or to locate the thermocouple, you might also not feel confident enough to proceed with any repairs or fixtures!

However, locating these two is not so difficult in fact. But before you grab your tools and head off to fix the problem, make sure you shut off power to the furnace by switching the breaker to the off position. Also, close the gas valve. You must be sure that you will be working safely!

To spot the thermocouple, locate the pilot light and look for the tip of a copper rod very nearby. Found it? Great! That’s the thermocouple. What if you can’t find the pilot light itself? Well, in this case, it makes sense to inspect your unit thoroughly since some of them may not have standing pilots at all! 

This type of pilot light is more typical for older furnaces, but newer versions have intermittent pilot lights or hot surface igniters. If this is your case, the pilot will only light when the thermostat makes a command for heat.

Well, this is all that we wanted to share with you today on the issue of improperly working pilot light in your gas furnace. If you tend to notice that your gas furnace stops working and its pilot light goes off way too frequently, especially during the winter days or when it is windy outside, the problem might be in that. 

However, now you know that there are several other reasons why pilot light can go out leaving you in a cold house or apartment in the middle of the night. Fortunately, now you are informed about the possible reasons, as well as about the ways of fixing this issue. 

Nevertheless, if your particular case is really serious, and/or you don’t feel much confidence to fix your pilot light on your own, better call the professionals to help you out with that. 

Frequently Asked Questions

⭐ Why does the pilot light keep going out on my wall heater in my apartment?

It can happen because of the broken thermocouple.

⭐ How often shall my gas heater be checked?

Once a year is usually enough.

⭐ How much does it cost to repair my gas heater if the pilot light is broken?

Repairing your furnace igniter will cost nearly 300 dollars at most. The flame sensor repair may cost around 75 to 250 bucks. So the average cost will vary from 100 to 400 dollars.


Written by
Camilla is an experienced Consultant with more than 20 years of preparing professional articles for numerous online resources. She has done a tremendous job and has learned a lot during her career. Camilla will advise you on the latest trends and give amazing tips on how to decorate a house.
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