The basic steps to relight a gas water heater pilot
To relight your gas water heater's pilot light, you will need to locate the control knob (usually on the front of the tank), turn it to the "Off" position, wait five minutes for gas to clear, then switch it to "Pilot." Hold a lit match or lighter near the pilot opening while pressing the ignition button or knob, depending on your model. Once the small flame catches, release the button and turn the knob to "On." The pilot should stay lit; if it goes out within a few minutes, the thermocouple may need replacement.
The entire process typically takes less than ten minutes. Most water heaters have clear instructions printed on a label attached to the tank itself—read these first, as some models vary slightly. If your heater has an electronic igniter instead of a manual pilot light, you may only need to press a button rather than use a match.
Key Takeaways
- Always turn the control knob to "Off" and wait five minutes before attempting to relight the pilot to let any gas dissipate safely.
- The pilot opening is usually a small hole near the bottom of the tank; you will need a lit match or lighter and steady hands to ignite it.
- If the pilot light goes out repeatedly within minutes of relighting, the thermocouple (a safety sensor) is likely failing and needs professional replacement.
- If you smell gas at any point or cannot relight the pilot after three attempts, turn off the gas supply and call a licensed technician.
Locating the pilot light assembly on your tank
The pilot light sits at the base of your water heater, usually protected by a small metal cover or access panel. On most tanks, this panel is held on by a single screw or clips and can be removed by hand. Once removed, you will see a small brass or copper tube running down from the control knob area—this is the pilot tube, and the opening where the flame sits is at the very end of it, close to the ground.
The control knob itself is mounted on the front or side of the tank, typically labeled with three positions: "Off," "Pilot," and "On." Some older models may have a fourth position marked "Hot" or a temperature dial. Before you touch anything, take a photo of the label with your phone so you can reference the exact sequence if you forget the order of steps.
Preparing the tank and clearing old gas
Turn the control knob all the way to "Off" and leave it there for a full five minutes. This waiting period is not optional—it allows any gas that may be lingering in the pilot tube to escape safely. Skipping this step or rushing it increases the risk of a small pop or flame when you try to relight.
While you wait, gather your tools: a long-handled lighter or a long match (fireplace matches work well because they burn longer). A flashlight is also helpful so you can see the pilot opening clearly. Do not use a regular short match—your fingers will get too close to the flame. If you do not have a long lighter or matches on hand, this is a good time to find one rather than improvise with something unsafe.
Igniting the pilot light with a match or lighter
After the five-minute wait, turn the control knob to "Pilot." You should hear a faint hissing sound, which means gas is now flowing to the pilot tube. Light your match or lighter and hold it near the pilot opening—you are aiming for the small hole at the end of the pilot tube, not the tube itself.
At the same time, press and hold the ignition button (usually located on the control knob or nearby on the tank). The button serves two purposes: it opens a valve to let gas flow and, on some models, it triggers a spark. Keep the flame near the opening and hold the button down for about 30 seconds. You should see a small blue flame appear. Once it does, release the button and remove the match or lighter.
The flame should stay lit on its own. If it goes out when ready, wait a few seconds and try again. Most pilots light on the second or third attempt. If the flame stays lit for at least one minute, turn the control knob to "On" to restore normal operation.
What to do if the pilot light will not stay lit
If the pilot light ignites but goes out within a few minutes of turning the knob to "On," the problem is almost always a faulty thermocouple. This is a safety device that sits in the pilot flame and tells the gas valve to stay open. When the thermocouple fails, the valve closes automatically, shutting off gas to the pilot. Thermocouples are inexpensive parts (typically $15 to $30) but require a professional to replace because the work involves disconnecting gas lines.
Do not attempt to replace the thermocouple yourself unless you have plumbing experience. Call a licensed plumber or your water heater manufacturer's service line. Before you call, note how long the pilot stays lit—this information helps the technician diagnose the problem faster.
Safety steps if something goes wrong
If you smell gas at any point during this process, stop when ready. Turn the control knob to "Off," leave the area, and call your gas company's emergency line from outside the house. Do not use electrical switches, light a match, or do anything that could create a spark. Gas leaks are rare during a straightforward pilot relight, but the smell of gas is always a signal to evacuate and call for help.
If you cannot relight the pilot after three careful attempts, or if you relight it but it goes out and will not stay lit even on the second try, stop trying. Turn the knob to "Off" and call a technician. Repeatedly trying to ignite a pilot that will not catch can waste gas and is frustrating without being productive. A professional can diagnose whether the problem is a thermocouple, a dirty pilot opening, a gas supply issue, or something else entirely.
When to call a professional instead
You should contact a licensed plumber or your water heater manufacturer's service line if: the pilot light will not ignite after three attempts; the pilot lights but goes out within a few minutes; you smell gas; the control knob is stuck or will not turn; or the tank is leaking water. These situations point to problems beyond a straightforward pilot relight—usually a faulty thermocouple, a clogged pilot opening, a gas supply problem, or a failing valve.
If your water heater is still under warranty, check the paperwork before calling a plumber. Many manufacturers offer free service calls for the first year or two. If you are renting, contact your landlord or property manager instead of calling a technician yourself; they are responsible for water heater repairs.
Frequently Asked Questions
How do I know if my pilot light is actually off?
Look through the small access panel at the base of the tank. If you see a small blue flame, the pilot is on. If you see nothing, it is off. In dim light, use a flashlight. The pilot flame is small—about the size of a match head—so look carefully.
Can I use a regular lighter instead of matches?
Yes, but a long-handled lighter or fireplace matches are safer because they keep your hand farther from the flame. A regular butane lighter works, but your fingers will be closer to the heat. Whatever you use, make sure it produces a steady flame you can hold for at least 30 seconds.
What if the pilot light keeps going out after I turn it to "On"?
This almost always means the thermocouple is failing. The thermocouple is a safety device that sits in the pilot flame; when it fails, the gas valve closes automatically. You will need a professional to replace it. Do not keep relighting it—call a plumber instead.
Is it dangerous to relight the pilot myself?
No, relighting a pilot light is a safe, routine task if you follow the steps: turn off the gas, wait five minutes, and use a match or lighter. The danger comes only if you skip the waiting period, smell gas, or ignore warning signs like a pilot that will not stay lit.
How long should I hold the ignition button down?
Hold it for about 30 seconds while the flame is near the pilot opening. This gives the thermocouple time to heat up and signal the gas valve to stay open. If nothing happens after 30 seconds, release the button, wait a few seconds, and try again.