How to Safely Relighting a Pilot Light on Your Gas Furnace

The Short Answer Is: It is generally safe for a homeowner to relight a furnace pilot light, as long as they follow proper precautions and guidelines. To do it yourself, first, turn off the furnace's gas supply and wait for a few minutes to allow any lingering gas to dissipate. Then, follow the manufacturer's instructions, which typically involve turning the gas valve to "pilot," igniting the pilot light with a long lighter or match, and holding the pilot button down for a minute before turning it to the "on" position. If you encounter difficulties or are unsure, it's advisable to consult a professional furnace repair technician to ensure safety and correct operation.

At one time, all gas furnaces had pilot lights. Now, however, most modern furnaces have entirely electric ignition switches. If the furnace in your Ohio home still has a pilot light, you want to know how to relight it. This is a skill that will allow you to troubleshoot safely and successfully one of the most common furnace problems.

Why Do Pilot Lights Go Out?

There are many reasons why your gas furnace pilot lights go out. Sometimes furnaces are housed in drafty basement areas or other low-lying parts of the property. If someone has recently slammed a door too hard, this may have extinguished the flame. Having a pilot light go out once every so often isn’t a big deal, especially if you know how to relight it on your own. In fact, this issue is so common with these components that furnace manufacturers have sought to prevent it entirely by upgrading their models to include electric ignition switches. Electric ignition switches are believed to be safer, far more consistent in performance, and far more reliable in this application overall. If you’re tired of having to relight your pilot, upgrading your heating equipment may be a worthwhile consideration.

However, pilot lights sometimes go out as a way of preventing or mitigating dangerous health hazards. If the pilot light constantly turns off, even just after it’s been relit, the thermocouple is the component that’s most likely having problems. This is a tiny rod that physically connects with the pilot flame. When the pilot light goes out, the thermocouple deactivates the gas to prevent a gas leak. It does so by closing the gas valve off. This component might be dirty, bent, or completely broken. When the thermocouple is dirty, accumulated soot will keep it from coming in direct physical contact with the gas flame. If age-related wear, bending, or other deformation has occurred at the thermocouple, simply relighting the pilot won’t solve the problem.

Where Is Your Furnace’s Pilot Light?

Before starting any furnace troubleshooting or repair, shut the heating system off at the circuit breaker. If this eliminates overhead lighting in the area, bring a good flashlight or other work light with you. You can find the exact location of your pilot light by consulting your owner’s manual. On most furnaces, the pilot is at the base of the furnace, just behind a small access door. It should be clearly labeled and have various warning stickers on the outside of the access door or on its interior. Take the time to read these warnings before proceeding, especially if this is your first time relighting the pilot.

Once you’ve opened the access door, you’ll see a small knob with three different settings. This is the reset button for your pilot light. It is also the only button you’ll need to touch while relighting this component.

Always Refer to Your Owner’s Manual

Although general furnace troubleshooting tips for the pilot light typically work well across all older furnace models, the heating equipment you own may have several nuances and special requirements that aren’t met by these or other general recommendations. Before attempting to relight the pilot in your home, take the time to refer to your owner’s manual. If you cannot find this manual, have never had it, or don’t understand its instructions, you can:

  • Look for a Digital Copy of the Manual Online
  • Contact the Furnace Manufacturer Directly
  • Have a Licensed HVAC Company Light the Pilot for You

While relighting the pilot is a relatively easy troubleshooting task, watching a professional do it first could be the best bet. When we send a technician from Buckeye Heating, Cooling & Plumbing to provide these services, we walk homeowners through the process step by step. This way, they can confidently relight their pilots on their own. More importantly, if there are any health hazards or other problems that are causing the pilot to go out, we can identify these and resolve them at the time of service.

Understanding and Using the Reset Switch for Your Pilot Light

Once you’ve found the pilot and its reset switch, you’ll need to set this switch to the “Off” position. All pilot light reset switches have three settings. These are “Pilot,” “Off,” and “On.” Turning the reset switch to “Off” will stop the flow of gas to this component. To do so, you will need to push the reset switch in or depress it and then slowly dial the knob over to “Off”. Keep the reset switch in the “Off” position for approximately one to two minutes. This is necessary to allow all residual gas to dissipate.

Before lighting the unit, turn the reset switch to “On” and keep it depressed. This will restore gas flow so that the unit can hold a flame. If you turn it to the “On” position but do not keep it depressed, the device will not light. Have a lighter or match handy so that you can quickly apply the flame after the button has been depressed in the “On” position for approximately three to five seconds. For obvious reasons, lighters work best for this task. After all, it’s difficult to keep the reset button depressed and strike a match simultaneously.

What to Expect After Relighting Your Pilot Light

You should continue holding the reset switch in the “On” position until the flame holds and burns steady. If there are no problems with your heating equipment, the flame should remain even after the button is no longer depressed. Once it does, you can close the access door, restore power to the heating system and test your heater at the thermostat. Continually trying to relight a pilot light that keeps going out isn’t safe. However, if the pilot light goes out again after your very first effort, you can restart the entire process and try to relight it one more time.

After two failed attempts, it is best to assume that other problems exist. Turn the reset button back to the “Off” position and call an HVAC company right away. You may have a cracked or dirty thermocouple or some other potentially hazardous furnace issue. Older furnaces often shut themselves off at the pilot light as a way of averting disaster.

Preventing Pilot Light Problems

With a quality, well-maintained furnace, relighting the pilot on your own shouldn’t be a big deal. If you have an especially drafty basement and your heating equipment has already been inspected and cleared for other issues, this may be something that you have to do often, especially during the windy winter months. The surest ways to keep your pilot light from going out include having the thermocouple and all other components regularly inspected and discouraging building residents from forcefully opening and slamming doors that lead to the furnace storage area.

Even when no problems exist at the thermocouple, having a pilot light constantly go out can be very frustrating. It may be time to think about upgrading to a more modern furnace design so that you can enjoy the convenience of having a heater with an all-electric ignition system. At Buckeye Heating, Cooling & Plumbing, we offer reliable Columbus, OH furnace repair to residents around Central Ohio. We also provide HVAC maintenance agreements and indoor air quality services. Call us today to schedule an appointment or to learn more about the many HVAC products we supply.

Related Reading