Do You Know How to Safely Relight Your Furnace?

If you haven’t replaced the gas furnace in your Indianapolis home for quite some time, odds are it has a pilot light. While most new furnaces have electric ignition switches, older furnaces don’t. The pilot light in your furnace is a small flame that ignites the burners whenever the heater is turned on at the thermostat. If it goes out, you won’t get any heat at all. Fortunately, you can use the information below to safely relight it.

Understanding the Common Reasons Why Pilot Lights Go Out

Having a pilot light go out isn’t usually a big deal. However, if it continues to go out after multiple attempts to relight it, it may be an indication of an underlying problem. Your furnace could simply be in a less-than-ideal location. Although the pilot light is situated behind an access door, if your furnace happens to be in a drafty garage or basement, you may find yourself kneeling in front of this access door quite often. Sometimes simply closing a nearby door too forcefully can blow this light out. If a drafty storage area or a firmly shut door are potential causes of the issue, take steps to resolve them. Sealing up drafts in low-lying areas of the home can both limit pilot light problems and save you money on your heating bill. Installing soft-closing hinges on your basement or garage door is another quick and easy fix.

In other instances, a pilot light that won’t stay lit indicates issues at the thermocouple. This is a tiny rod that prevents home emergencies by shutting the gas supply off if gas leaks are suspected. The thermocouple comes in direct contact with the pilot light flame. If no flame exists, the thermocouple will instantly turn off the flow of gas to the pilot. When this shut-off occurs while the pilot light is still burning, the flame will invariably flicker out on its own.

Problems at the Thermocouple

Sometimes problems at the thermocouple aren’t actually indicative of a gas leak. Instead, they may mean that the thermocouple itself is broken, dirty or otherwise not up to the task. If you haven’t paid for professional furnace maintenance in quite some time, your thermocouple could be covered in too much dirt or soot to actually come in contact with the pilot. Over time, and with constant exposure to the heat of the pilot light flame, thermocouples gradually warp and bend. These distortions render them ineffective and leave homeowners with pilot lights that refuse to say lit.

When it comes to relighting your pilot light safely, it’s important to be aware of all the possible reasons why the flame has gone out. After just two attempts to light a furnace pilot, it’s always best to call HVAC repair professionals in. There’s a good chance that you have a slight gas leak on your hands, and there’s a very high likelihood that you’ve got a worn or damaged thermocouple.

Finding and Familiarizing Yourself With the Pilot Light

If you’ve never relit a furnace pilot light before, this job can certainly be intimidating. You may have heard a few horror stories about the possible mishaps that can occur, and the listed steps for relighting this flame can sometimes be confusing. Thus, the best way to start is by getting familiar with your own heating equipment. Dig out your owner’s manual and read up on this component before attempting to get the job done. If you can’t find this manual, search for a digital copy on the web and read through it on your phone, laptop or tablet. This guide will tell you exactly where the pilot light is located on your furnace, and it will even have detailed drawings of what it looks like. If the overhead lighting in your basement or garage isn’t great, bring a flashlight or other focused work light along.

You’ll likely find the pilot light just behind a small access door near the base of your heater. When you swing this door open, you’ll see the small space where the flame should be and a bright red dial with “OFF,” “ON” and “PILOT” settings. This is the reset switch for the pilot. It is the only thing that you’ll need to touch when relighting the pilot.

Turn Your Heater Off

It’s never a good idea to attempt troubleshooting, cleaning, repairing or maintaining your heater in any way while it’s still turned on. Turn your heater off at the thermostat, and then shut it off at the circuit breaker if necessary. When you head back down to your furnace, bring your flashlight, your owner’s manual and a working lighter with you. Although furnace pilot lights can be lit with matches, one of your hands will need to be free to handle the reset switch.

Reset Your Pilot Light

Open the access door and turn the pilot light reset switch to the “OFF” setting. To do so, you will need to firmly push the button in before turning it. Hold it in this position for two full minutes. This is one of the most important steps in safely relighting a pilot. It shuts off the flow of gas to the pilot. Waiting for two minutes ensures that any remaining gas fully dissipates before you lift your lighter or strike your match.

After you’ve waited two full minutes, toggle the switch to the “ON” position and keep it firmly depressed. This will restore the flow of gas to the pilot so that it both relights and holds its flame. After waiting several seconds for the gas to arrive, light the pilot while continuing to depress the reset button. Hold the reset button for a few seconds, and then gently let it go. If there are no problems with the thermocouple or pilot, the flame should hold.

Check Your Work

Carefully close the access door and clean up any items that you’ve brought along with you. You never want to leave any miscellaneous clutter too close to your furnace. Turn the furnace back on first at the circuit breaker and then at the thermostat. Listen to hear the heater fire up. If the heater does not turn on, check the pilot light to see if it’s gone out again. If it has, you can repeat the steps for relighting it one more time. However, if it continues to go out, assume that there’s an underlying problem and seek help.

Preventing Pilot Light Problems

With a new, modern furnace, you can avoid the wintertime hassle of having to constantly relight your pilot. Making this upgrade might be the best choice if your pilot light is regularly being blown out by basement drafts that you can’t completely eliminate. Although furnaces are built to last for up to two full decades, a furnace that’s well past it’s 10-year mark has already lost approximately half of its efficiency, and it’s bound to face increasing repair issues as the years wear on.

Peterman Brothers has been providing reliable HVAC services throughout the Greater Indianapolis area since 1986. We install, maintain and repair both heating and cooling equipment. Our clients can also count on us for a full range of plumbing, electrical and sump pump services. If you’ve been having a hard time keeping your furnace’s pilot light lit, we can help. We can also give you a step-by-step demonstration on how to safely tackle this task yourself. Call us today for an appointment.

Skip to content