How to Reset & Relight a Water Heater Pilot Light (Step-by-Step)

No hot water and you've got a gas water heater? Often the culprit is a pilot light that's gone out. Relighting it is something many homeowners can safely do — and this step-by-step guide walks you through it, plus what to do when the pilot refuses to stay lit.

Safety First

Before anything: if you smell gas, stop. Don't try to light anything. Leave the area, and from a safe location contact your gas utility or call for emergency service. A persistent gas smell is never a DIY situation. Only proceed if there's no gas odor.

How to Relight the Pilot

Exact steps vary by model, so read the label on your unit — but the general sequence is:

1. Turn the gas control dial to "Off" and wait at least five minutes for any residual gas to clear. Don't rush this step.
2. Turn the dial to "Pilot."
3. Locate the pilot through the burner access opening near the base.
4. Press and hold the control knob (this allows gas to the pilot) and press the igniter button repeatedly until the pilot flame lights. On older units without an igniter, use a long lighter while holding the knob.
5. Keep holding the knob for about 30–60 seconds after the flame lights, so the thermocouple heats up and signals the valve to stay open.
6. Release the knob. If the pilot stays lit, turn the dial back to "On" and set your temperature.

When the Pilot Won't Stay Lit

If the flame dies the moment you release the knob, the usual suspect is a faulty thermocouple — the sensor that tells the gas valve the pilot is burning. When it fails or is dirty, the valve shuts the gas off as a safety measure. Other causes include a dirty pilot orifice, a draft, or a failing gas valve. This is a common and affordable fix: our pilot light & thermocouple repair service handles it.

If repeated relighting fails, or the pilot lights but the burner won't fire, it's time for a professional water heater repair. And if your unit is old and increasingly troublesome, weigh the cost against a replacement.

When to Stop and Call a Professional

Relighting a pilot is a reasonable DIY task, but a few situations call for a pro instead. If you ever smell gas, stop entirely — leave the area and contact your gas utility or emergency service rather than attempting to light anything. If the pilot lights but won't stay lit after two or three careful attempts, that's almost always a failing thermocouple and needs a part, not another try. The same goes for a pilot that lights but a burner that won't fire, repeated outages over days, or any soot, scorching, or yellow (rather than blue) flame — all signs of a combustion or venting problem that shouldn't be ignored.

There's no shame in calling early; the failures above are common, affordable fixes, and forcing a unit that keeps dropping its pilot can mask a real safety issue. If you're unsure, a quick water heater repair visit settles it.

Frequently Asked Questions

How do I relight a water heater pilot light?

Turn the gas control to "Off" and wait five minutes, switch to "Pilot," then press and hold the control knob while pressing the igniter until the pilot lights. Keep holding for 30–60 seconds so the thermocouple heats, then release and turn the dial to "On."

Why won't my pilot light stay lit?

The most common cause is a faulty or dirty thermocouple, the sensor that keeps the gas valve open once the pilot is burning. A draft, a clogged pilot orifice, or a failing gas valve can also be responsible.

Is it safe to relight a pilot light myself?

If there's no gas smell, many homeowners can safely relight a pilot by following the unit's instructions. If you smell gas at any point, stop immediately, leave the area, and contact your gas utility or emergency service rather than attempting to light it.

What is a thermocouple and why does it matter?

A thermocouple is a safety sensor that detects the pilot flame and signals the gas valve to stay open. If it fails, the valve shuts off the gas, so the pilot won't stay lit — a common, affordable repair.