What Is a Furnace Pilot Light and How to Reignite Safely

Knowing how to safely relight a furnace pilot light is a must for homeowners. A functioning furnace is vital to keeping your home warm this winter. 

Sometimes relighting your furnace pilot light requires a professional. Call on furnace repair professionals in Lee’s Summit, MO, for safe and expert furnace repair services. 

What Is a Furnace Pilot Light? 

All gas furnaces have a pilot light. The pilot light on a furnace refers to the blue flame located inside a gas furnace. It is a small gas flame kept burning continuously to light a larger burner in the furnace. 

The pilot light is usually located near the bottom of a gas furnace. Be sure to check the furnace’s instructions to properly locate your furnace pilot light. 

How to Safely Reignite a Furnace Pilot Light

As mentioned above, a pilot light is a small flame and burns on gas, so take caution when reigniting it. 

Step One: Gather the Necessary Tools 

Relighting a pilot light can be straightforward, but it does require a few basic tools. The tools needed to relight a furnace pilot light are typically: 

●      A long-handled match or lighter

●      A flashlight 

Step Two: Read the Instructions & Locate the Pilot Light

Any at-home DIY project should be done with care and should always start with looking at the instructions. Older furnaces may be different than newer models, so don’t skip out on reading the pilot light instructions just because you have the latest model. 

Furnace pilot light instructions should be located on the furnace label. If you are unable to find a label, the instructions should be in the furnace’s manual. 

To locate the pilot light, use your flashlight. It could be on the bottom of the furnace and will have three indicators: on, off, and pilot. Once you have read the instructions and located the pilot light, you’re ready to move on to step three. 

Step Three: Let Out Any Trapped Gas

There should be a knob next to the pilot light indicators. Switch this to the “off” position from its standing position. Once your pilot light has switched off, wait at least five minutes for the trapped gas to dissipate. You should never try to relight your pilot light without turning off your furnace first. 

Allowing the gas to dissipate is an essential step to safely relighting a pilot light. This is because it reduces the likelihood of starting a fire. As the gas dissipates, locate the “reset” button and move on to step four. 

Step Four: Carefully Reignite the Pilot Light

Now that the gas has dissipated, turn the knob to “pilot.” Hold the “reset” button down and reignite the pilot light with your long-stem match or lighter. The pilot light should reignite with a small blue flame. When the pilot light ignites, release the “reset” button. Now your pilot light has been reignited. 

Be sure to use caution when handling open flame, especially near your furnace. Any open flame can be a hazard, so try to keep your hands and body as far from the flame as you can. 

When Your Pilot Light Doesn’t Reignite

Unfortunately, even if the above steps are followed perfectly, sometimes the pilot light will not reignite. This could be due to many things, but looking to a furnace repair and maintenance specialist is your best bet when these steps don’t work. 

If you go through these steps and your pilot light ignites but then goes out after releasing the reset button, the issue could be your thermocouple. This indicates that there may be a blockage in your pilot tube. In this case, and any others resulting in pilot light outages, call a professional to help. 

Causes of Furnace Pilot Light Outages 

Some causes of pilot light outages are more serious than others. It could be as simple as going through the above steps or it could require a professional repair or replacement. Some examples of possible causes of a pilot light going out are: 

A Faulty or Dirty Thermocouple 

A thermocouple or flame sensor is the part of your furnace that shuts the gas off when the pilot light goes out. If the thermocouple is faulty or dirty, you will want to enlist an experienced professional. If you think it may be the thermocouple, shut the power to your furnace off and close the gas valve. 

If the case is that the thermocouple is failing to shut the gas off, it could be dangerous, so don’t proceed without an experienced technician. 

Gas Issues or Gas Regulator Issues 

A gas regulator issue will directly affect your pilot light and all of your gas appliances like a water heater. Usually, this will be an obvious issue that requires a call to the gas company and a regulator replacement. 

If your pilot light goes out due to a gas-related issue, it could be that the natural gas in your area has reached its consumption level. In this case, you should go through these steps after waiting a short time. If the steps indicated above don’t result in a lit pilot light, call the gas company. 

Airflow Issues

If you notice that your pilot light continues to go out after you reignite it, you may have an airflow issue. This could indicate a draft in your duct output or intake air registers. If your intake air registers are closed off, it will create a suction effect that causes the pilot light to go out. You will want to seal any drafts and keep your air registers open to remedy or avoid this issue.

When to Call a Furnace Repair Professional

When preparing a furnace for winter, a professional will make sure your furnace won’t go out on the coldest night. On older furnaces, this should be done as a preventive measure. A professional will be able to fix any faulty components of your furnace and avoid mishaps. 

If your efforts to reignite your pilot light have proven ineffective, our technicians at Air Unlimited Heating & Cooling are ready to help. Call us today at (816) 286-7258.

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