The basic steps to light an electronic pilot
To light a gas heater with an electronic pilot, locate the ignition button on the control panel—usually labeled "Igniter," "Pilot," or with a spark symbol—and press it repeatedly while holding the gas control knob in the "Pilot" position. The electronic igniter creates a spark at the pilot burner. Once you see a small flame appear at the pilot, continue holding the gas knob in "Pilot" for 30 to 60 seconds to let the thermocouple warm up and sense the flame. Then turn the gas knob to "On" and release the ignition button.
If the pilot does not light after 10 to 15 button presses, stop and wait five minutes before trying again. Pressing the igniter too many times can flood the pilot chamber with gas, making it harder to light. After the pilot is lit and you have switched the gas knob to "On," the main burner should ignite within a few seconds.
Key Takeaways
- Press the ignition button while holding the gas control knob in "Pilot" position until you see a small flame at the pilot burner.
- Keep the gas knob in "Pilot" for 30 to 60 seconds after the flame appears so the thermocouple can detect it.
- If the pilot does not light after 10 to 15 attempts, wait five minutes before trying again to avoid flooding the chamber.
- Turn the gas knob to "On" once the pilot is burning steadily, and the main burner should start within seconds.
- If the pilot lights but goes out when you release the gas knob, the thermocouple may need cleaning or replacement.
Where to find the ignition button and gas control knob
The ignition button and gas control knob are always on the front of the heater's control panel, which is usually located on the lower front or side of the unit. The gas control knob is a dial with three positions: "Off," "Pilot," and "On." The ignition button sits next to it, sometimes recessed slightly into the panel to prevent accidental pressing.
On some models, the ignition button is a push-button; on others, it is a piezo-electric spark generator that you press repeatedly. The button may be red, black, or silver. If you cannot find either control, check the heater's manual or look for a label on the panel itself—manufacturers usually mark these clearly because they are the most-used controls.
Holding the gas knob in Pilot position
The "Pilot" position on the gas control knob allows a small amount of gas to flow to the pilot burner without igniting the main burner. You must hold the knob in this position while pressing the ignition button and for 30 to 60 seconds after the pilot flame appears. Do not release it early, or the flame will go out before the thermocouple heats up enough to keep it burning.
The thermocouple is a safety device that senses heat from the pilot flame. If it does not get warm enough, it will shut off the gas supply as soon as you release the knob, thinking the pilot has failed. Holding the knob for the full 30 to 60 seconds ensures the thermocouple reaches its operating temperature. You will feel slight resistance as you turn the knob—this is normal.
What to do if the pilot will not light
If you press the ignition button 10 to 15 times and see no spark or flame, stop when ready and wait at least five minutes. Repeated ignition attempts can flood the pilot chamber with unburned gas, which makes ignition harder and can be a safety hazard. After waiting, try again with fresh attempts.
If the pilot still will not light, check that the gas supply to the heater is turned on at the main valve. Look for a gas shutoff valve near the heater or at the wall where the gas line enters—it should be parallel to the gas line, not perpendicular. If the valve is off, turn it parallel to the line to open it. If the gas is on and the pilot still will not light after several attempts, the igniter may be faulty or the pilot opening may be clogged with dust or debris. At that point, the heater will need service from a technician.
Why the pilot goes out after you release the gas knob
If the pilot lights when you press the ignition button but goes out as soon as you release the gas knob from "Pilot" to "On," the thermocouple is not detecting the flame properly. This usually means the thermocouple needs cleaning or has failed. A thermocouple is a thin metal rod that sits in the pilot flame; if it is covered with soot or corrosion, it cannot sense the heat.
To clean the thermocouple, turn off the gas at the control knob and wait for the heater to cool. Locate the thermocouple—it is a thin metal tube running from the pilot burner assembly—and gently wipe the tip with a soft, dry cloth or fine steel wool. Do not bend it or explore heavy pressure. Turn the gas back on and try lighting the pilot again. If it still goes out, the thermocouple has likely reached the end of its life and needs replacement by a technician.
Switching from Pilot to On position
Once the pilot flame is burning steadily and you have held the gas knob in "Pilot" for 30 to 60 seconds, turn the knob clockwise to the "On" position. This opens the gas supply to the main burner. The main burner should ignite within a few seconds—you will hear a whoosh or see a larger flame appear in the combustion chamber.
If the main burner does not ignite within 10 seconds, turn the gas knob back to "Off" and wait a minute before trying again. Do not leave the gas knob in "Pilot" indefinitely; if the main burner does not start after two or three attempts, there may be an issue with the burner itself or the gas line, and the heater should be inspected by a technician.
Safety steps to follow every time
Before lighting the pilot, smell around the heater for the odor of natural gas or propane. Gas companies add a rotten-egg smell to these fuels so leaks are straightforward to detect. If you smell gas, do not light the pilot. Turn off the gas at the main valve, open windows and doors, and leave the building. Call your gas company or emergency services from outside.
Never force the gas control knob or ignition button. If either feels stuck or broken, stop and do not attempt to light the heater. Keep your face and hands away from the pilot opening while pressing the ignition button—the spark is harmless, but the flame can appear suddenly. After the heater is running, do not touch the pilot area or any part of the burner assembly until it has cooled completely, which can take 30 minutes or more.
Frequently Asked Questions
How many times should I press the ignition button before I give up?
Press the ignition button 10 to 15 times while holding the gas knob in "Pilot." If you do not see a spark or flame after that, stop and wait five minutes. Pressing more than 15 times can flood the pilot chamber with gas and make the situation worse. After waiting, you can try another round of 10 to 15 presses.
What does it mean if I see a spark but no flame?
A spark without a flame usually means gas is not reaching the pilot burner, or the gas is not igniting. Check that the gas control knob is fully in the "Pilot" position and that the main gas valve to the heater is open. If both are on, the pilot opening may be clogged with dust or debris. A technician can clean or clear the pilot burner.
How long should I hold the gas knob in Pilot before switching to On?
Hold the gas knob in "Pilot" for 30 to 60 seconds after the pilot flame appears. This gives the thermocouple time to heat up and sense the flame. If you switch to "On" too quickly, the thermocouple will not be warm enough, and the pilot will go out when you release the knob.
Can I light the pilot if the heater is cold?
Yes, you can light the pilot on a cold heater. The electronic igniter does not require the heater to be warm. However, if the heater has been off for a long time, air may be trapped in the gas line, which can make the pilot harder to light. If it does not light on the first attempt, wait five minutes and try again.
What should I do if the main burner does not start after I turn the knob to On?
Turn the gas knob back to "Off" and wait one minute. Make sure the pilot is still burning. If it is, try turning the knob to "On" again. If the main burner still does not start after two or three attempts, or if the pilot goes out, stop and contact a technician. Do not keep trying, as this can waste gas and create a safety hazard.