The pilot light on a gas water heater is a small flame that heats the water in the tank. Over time, debris, drafts, or a fallen flame can cause the pilot to go out. Reigniting the pilot light can restore hot water supply and energy efficiency when done safely and correctly. This guide outlines a practical, step by step process, plus safety precautions, troubleshooting tips, and maintenance ideas to prevent future outages.

Safety Precautions

Before attempting to reignite a pilot light, understand the potential hazards. Gas leaks, carbon monoxide, and scalding from hot water or metal components pose serious risks. If you smell gas, hear hissing, or suspect a leak, evacuate the area and contact the gas company or emergency services. Ensure good ventilation, keep flames and sparks away, and never skip the manufacturer’s safety instructions. If you are unsure, call a licensed plumber or HVAC technician.

Before You Begin

Gather the essential items: dry matches or a long lighter, flashlight, a clean rag, and the water heater’s manual. Confirm the thermostat is set to a reasonable temperature (usually around 120°F to 130°F). Turn off the gas supply at the shutoff valve and set the thermostat to the “pilot” position if the control knob has multiple settings. Allow any residual gas to dissipate for several minutes before attempting to light the pilot.

Tools And Materials

Long lighter or match
Flashlight
Rag or cloth for grip
Owner’s manual for model-specific instructions
Carbon monoxide detector installed in living spaces

Steps To Reignite Pilot Light

Access the Pilot Assembly: Locate the access panel on the side of the water heater. Remove screws or latches and open the panel to expose the burner area and gas control valve.
Turn Off Gas And Pressure: If the knob is on the gas control, rotate it to the “OFF” position. Wait at least five minutes to clear any accumulated gas. This waiting period reduces the risk of ignition from a stray spark.
Set To Pilot: After the wait, turn the knob to the “PILOT” position. This position allows you to light the pilot using a flame while keeping the main burner off.
Light The Pilot: Keep the knob in the “PILOT” position. While holding the knob in, use a long lighter or match to ignite the pilot flame at the burner. Maintain the flame for about 30 seconds to ensure it’s stable. If the pilot does not light after several attempts, stop and recheck gas supply and obstructed thermocouple.
Release And Check: After the flame is stable, release the knob slowly to the “ON” position. The main burner should ignite. If the burner does not ignite automatically, turn the gas supply back on and try again, ensuring the pilot remains lit.
Replace The Access Panel: Secure the panel and confirm there are no gas leaks around the fitting. If a faint gas odor persists, do not operate the heater; contact a professional.

What If It Won’t Stay Lit?

Common reasons a reignited pilot goes out include a dirty or faulty thermocouple, a faulty gas valve, insufficient gas pressure, drafts near the vent, or a misaligned flame. If the flame flickers or goes out after several minutes, discontinue attempts and inspect the thermocouple and connections. A dirty thermocouple can be cleaned gently with a soft brush; a faulty thermocouple or gas valve usually requires professional service. Do not bypass safety devices or attempt to fix gas components beyond basic cleaning.

Troubleshooting Common Issues

Pilot Won’t Light: Ensure the gas supply is on, the control knob is in PILOT, and there is no obstruction in the burner. Re-execute the lighting steps, keeping a steady flame.
Pilot Lights Then Goes Out: The thermocouple may be cooling too quickly or out of proper position. Light the pilot and keep the knob depressed for about a minute to allow the thermocouple to heat. If it still drops, inspect alignment and connections.
Gas Odor: If you smell gas, vacate the area immediately and contact the gas company. Do not attempt to light the pilot again.
No Hot Water After Lighting: Confirm the thermostat is set correctly and the burner ignites when needed. Sediment buildup in the tank can reduce heating efficiency; consider flushing the tank if needed.

When To Call A Professional

Seek professional help if the pilot won’t stay lit after multiple attempts, if there is a persistent gas odor, if the thermocouple or gas valve appears damaged, or if the water heater is older than 10–15 years and shows signs of inefficiency or leakage. A licensed technician can diagnose gas pressure issues, venting obstructions, or unsafe wiring, and replace worn components safely.

Maintenance To Prevent Future Issues

Regular maintenance helps prevent pilot outages and extends water heater life. Schedule annual inspections, replace the thermocouple every 3–5 years as recommended by the manufacturer, and flush the tank yearly to remove sediment buildup. Keep vent paths clear, verify proper insulation, and test the water heater’s safety features periodically. Installing or maintaining a carbon monoxide detector near the unit adds an essential layer of safety for homes using gas appliances.

Additional Tips

Record model, serial numbers, and service dates for easy reference during future maintenance or repairs.
If you have a standing gas line, ensure the shutoff valve is easily accessible in case of emergency.
Consider upgrading to an energy-efficient water heater model if frequent issues persist or if the unit is nearing the end of its expected life.