How to Light a Boiler Pilot Light in 4 Simple Steps

Let there be light (and heat) 

A father with his son washing the dishes
Photo: MoMo Productions / DigitalVision / Getty Images
A father with his son washing the dishes
Photo: MoMo Productions / DigitalVision / Getty Images
Lawrence Bonk
Written by Lawrence Bonk
Contributing Writer
Updated December 13, 2023

Difficulty

Easy

You've got this!

Time to complete

5 minutes

You may spend a bit longer if you don’t exactly know where the boiler is and how to access it.

Cost

$0

Roll up your sleeves!

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What you'll need:

TOOLS
  • Long candle lighter or fireplace match
  • Flashlight (optional)

The humble boiler pilot light is the difference between a brutally cold winter and a nice comfortable time curled up with your favorite book and a cup of tea. If the pilot light isn’t lit, the boiler won’t be able to heat water for the purposes of temperature-regulation and good, old-fashioned baths, showers and dishwashing. Don’t worry. Lighting a boiler is a simple process, even for newbies. Keep reading and we'll walk you through it. 

Preparing to Light a Boiler 

First things first, you have to find the boiler, so head down to the basement or boiler room and take a look around. Boilers resemble hot water tanks, with obvious attachments to pipes, drains, shut-off valves, relief valves, and other plumbing fixtures. 

It is crucial to know what type of boiler you have before you begin: a manual boiler or an automatic ignition boiler. Look for a safety label on the front, indicating an automatic ignition type boiler. Barring that, look for a control knob on the top with two settings, on and off, as this also suggests an automatic ignition unit. If you don’t find either of these features, you have a manual boiler. Safety Note: Automatic ignition mechanisms are complex and should never be lit manually, though there is an electrical method to reset one outlined below.

How to Ignite a Manual Ignition Boiler 

Once you’re sure you’re looking at a manual boiler, relight the pilot light in these 4 steps.

How to Ignite a Manual Ignition Boiler 

Once you’re sure you’re looking at a manual boiler, relight the pilot light in these 4 steps. 

1. Turn the Boiler Off

Your first step is to turn the boiler off and lower the thermostat to its lowest possible setting. Look for the gas control knob, likely attached to a gray box on the floor at the front of the boiler, and set it to the “off” position. If you smell gas, let the odor dissipate for 15 to 30 minutes before moving on—it’s important to be patient here because lighting the boiler can be dangerous if you don't wait. If you can smell gas, keep waiting. You can open windows to help ventilate at this stage. 

2. Remove the Access Panel and Take a Peek 

A man inspecting a boiler
Photo: GregorBister / E+ / Getty Images

Next, remove the access panel, which leads to the pilot light. In the vast majority of cases, this panel is right next to the gas control knob box. Some are held with gravity clips, while others with finger screws, so remove the fasteners by your preferred method. This will reveal an access hole that you can peer into with a flashlight, or by using ambient light. Look for the pilot light orifice inside of this access hole, which looks like an upturned piece of metal tubing. 

3. Turn the Gas Control Knob 

Now it’s time to turn the gas control knob from the “off” position to the “pilot” position, which should be clearly labeled. Press down on the knob once you have it set to the pilot position, which will release gas into the orifice. 

4. Light the Pilot 

Grab your long candle lighter or fireplace match and insert it into the access hole to light the pilot light. Keep your other hand pressed down on the gas control knob as you do this, to allow the gas to grab ahold of that flame. Look for a blue flame, which lets you know the pilot light is sufficiently lit. Remove the lighter but keep your hand on the gas knob button for a few moments, to ensure it stays lit. 

How to Reset an Automatic Ignition Boiler 

Remember, you’re not lighting an automatic ignition boiler—you need a certified expert to do that. Here are 4 steps to reset your system so it lights itself.

  1. Turn Off the Electricity

    Start by shutting off the electrical switch that provides power to the boiler via an electrical box or the boiler itself. Failing that, just flip the appropriate breaker switch at the breaker panel.

  2. Turn Off the Gas and Remove the Access Panel

    Next, turn off the gas by switching the gas control knob to the “off” position. If you smell the tell-tale odor or gas, open up the windows and let the room ventilate for 15 to 30 minutes—again, be patient. Remove the access panel by turning finger screws or by simply lifting it up and pulling it off. This comes in handy later.

  3. Turn the Gas On

    A professional turning the gas on
    Photo: Minerva Studio / iStock / Getty Images Plus / Getty Images

    Once the room is vented and you no longer smell any lingering gas, turn the gas on by switching the knob to the “on” position. This will prepare the system for a reset in the next step. 

  4. Reset the System

    Turn the electricity back on by flipping the switch on the boiler itself via an associated panel or by switching the breaker back on in the box. Once you do that, listen at the access hole for a clicking noise. This noise should abate after 10 to 30 seconds, followed by the pilot light igniting in all of its glory. If the noise stops, but there’s no light, call in a technician. Otherwise, seal up the access point and enjoy a functioning boiler.

DIY vs. Hiring a Pro

Relighting a manual boiler is a DIY-friendly job and one that some homeowners have to do once or twice a season, depending on how old their boiler is. There are some caveats, however, when going the DIY route. First of all, you cannot light an automatic ignition system by yourself—that’s definitely a job for local boiler contractors. So you want to double-check, and even triple-check, to ensure you have a manual system. Also, if the light won’t start even when following the above steps, you likely won’t have the experience to dive too deep into troubleshooting. Having a pro on hand can speed up the diagnostic and repair process. 

Frequently Asked Questions

Even if you do everything right, your boiler’s pilot light might not come on. This has a number of possible causes, but the most common is a blocked jet. These jets are small and clog up even with a small amount of debris. You can clean it yourself or hire a pro to replace the component. Other possible causes include a faulty fan and frozen pipes, among others.

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Learn more about our contributor
Lawrence Bonk
Written by Lawrence Bonk
Contributing Writer
As a technology enthusiast with a professional focus on smart home appliances and accessories, Lawrence Bonk keeps a keen eye on the home improvement innovation space. He is constantly searching for new and convenient ways for homeowners and renters to make the most of their domiciles and has written for publications such as Huffington Post, Engadget, CBS, and many more.
As a technology enthusiast with a professional focus on smart home appliances and accessories, Lawrence Bonk keeps a keen eye on the home improvement innovation space. He is constantly searching for new and convenient ways for homeowners and renters to make the most of their domiciles and has written for publications such as Huffington Post, Engadget, CBS, and many more.
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