The basic steps to relight a pilot light

Relighting a pilot light is a task most homeowners can do themselves in five to ten minutes. The exact steps depend on whether your heater has an automatic ignition system or a manual one, but the principle is the same: you'll shut off the gas, wait for any residual gas to clear, then restart the ignition sequence.

Before you begin, locate your heater's control panel. This is usually on the front of the unit or on a side panel near the burner. You'll see three settings: "Off," "Pilot," and "On" (or sometimes "Heat"). You'll also see a small red or black button labeled "Ignite" or "Light"—this is what you'll press to create the spark that lights the pilot.

Keep your heater's manual nearby. If you don't have it, the model number is usually printed on a sticker on the unit itself, and you can search for the manual online. The manual will show you the exact location of the ignition button and any safety steps specific to your model.

Key Takeaways

  • Turn the control dial to "Off," wait 5 minutes for gas to clear, then turn it to "Pilot" before attempting to light.
  • Press and hold the ignition button while holding a long lighter or lit match near the pilot opening—you should see a small blue flame appear within 30 seconds.
  • Once the pilot is lit, keep holding the control button down for another 30 seconds so the thermocouple (a safety sensor) can warm up and keep the pilot burning.
  • If the pilot won't light after three attempts, stop and wait 5 minutes before trying again—repeated attempts can flood the chamber with gas.
  • If the pilot lights but goes out when you release the button, the thermocouple may be faulty and you'll need to call a technician.

Turn off the gas and wait

Start by turning the control dial all the way to "Off." This shuts off the gas supply to both the pilot and the main burner. Wait at least 5 minutes. This pause lets any gas that's already in the chamber dissipate, which is a safety step—it prevents a buildup of gas that could ignite suddenly when you light the pilot.

During this waiting period, open a window or door near the heater if you can. This helps any lingering gas escape and gives you fresh air while you work. If you smell gas strongly at any point, stop what you're doing, leave the area, and call your gas company's emergency line. Do not try to light the pilot if you smell gas.

Switch to pilot mode and prepare to ignite

After 5 minutes, turn the control dial to "Pilot." You should hear a soft hissing sound—this is gas flowing to the pilot burner. Now locate the ignition button. On most units, it's a small red or black button on the control panel itself. Some older heaters don't have an ignition button and require you to use a match or lighter instead.

If your heater has an ignition button, hold a long lighter or a lit match near the pilot opening (a small hole you can usually see on the burner assembly). Press and hold the ignition button at the same time. You should see a small blue flame appear at the pilot opening within 10 to 30 seconds. If nothing happens after 30 seconds, release the button, wait a moment, and try again.

If your heater requires a match or lighter, light the match or lighter first, then turn the dial to "Pilot" and hold the flame near the pilot opening. The pilot should ignite when ready when the gas reaches the flame.

Hold the button to let the thermocouple warm up

Once you see the pilot flame, keep holding the ignition button down for another 30 seconds. This is crucial. Inside the pilot assembly is a small metal rod called a thermocouple. When the pilot flame heats this rod, it sends an electrical signal that tells the gas valve to stay open. If you release the button too soon, the thermocouple won't be warm enough yet, and the gas valve will close, snuffing out the pilot.

After 30 seconds, slowly release the button. The pilot flame should stay lit. If it does, you've succeeded. Now turn the control dial to "On" (or "Heat" on some models) to restore gas to the main burner. The main burner should ignite from the pilot flame within a few seconds.

What to do if the pilot won't stay lit

If the pilot lights when you press the button but goes out as soon as you release it, the thermocouple is likely faulty. This is a safety device that's inexpensive to replace, but it requires a technician. Do not keep trying to light the pilot—each failed attempt wastes gas and can be frustrating. Call a heating technician instead.

If the pilot won't light at all after three attempts, stop and wait 5 minutes before trying again. Repeated ignition attempts can flood the pilot chamber with unburned gas, making it harder to light. After the 5-minute wait, repeat the process from the beginning. If it still won't light after a second round of three attempts, the ignition system may need professional service.

When to call a professional instead

If you smell gas during or after the lighting process, turn the dial to "Off" when ready and leave the area. Call your gas company's emergency number. Do not try to light the pilot again.

If the pilot lights and stays lit when you hold the button, but the main burner doesn't ignite when you turn the dial to "On," there may be a problem with the main burner assembly or the gas valve. This also requires a technician.

If you're uncomfortable working with gas appliances, or if you've tried these steps twice without success, call a licensed HVAC technician. They can diagnose the problem quickly and safely. Most heating companies offer emergency service during winter months, though response times and costs vary by location and time of day.

Frequently Asked Questions

How long should I wait before trying to light the pilot again if it doesn't work?

Wait at least 5 minutes. This lets any unburned gas in the chamber escape. Trying again when ready can cause gas to build up, which makes ignition harder and is a safety risk. After the 5-minute wait, repeat the full process from the beginning.

What does the thermocouple do, and why do I have to hold the button?

The thermocouple is a safety sensor that detects heat from the pilot flame. When it's warm enough, it signals the gas valve to stay open. Holding the button for 30 seconds gives the thermocouple time to heat up. If you release too soon, the valve closes and the pilot goes out.

Can I use any lighter to light the pilot, or does it have to be a specific type?

A long lighter (the kind used for candles or grills) works best because it keeps your hand farther from the flame. A regular lighter or a wooden match also works, but you have to get closer to the pilot opening. Avoid using paper matches—they burn too quickly.

Is it dangerous to relight a pilot light myself?

It's generally safe if you follow the steps carefully: turn off the gas, wait 5 minutes, and don't try more than three times in a row. The main risk is gas buildup if you attempt ignition repeatedly without waiting. If you smell gas at any point, stop and call your gas company.

Why does my pilot light keep going out after I turn the heater to "On"?

This usually means the thermocouple is failing. A faulty thermocouple can't hold the gas valve open once you release the ignition button. You'll need a technician to replace it. Don't keep relighting it—the problem won't fix itself.