Where to find the pilot light adjustment and what it controls
The pilot light adjustment on a gas fireplace is a small screw or dial located on the gas control valve, which sits behind or below the fireplace front panel. On most fireplaces, you'll find it near the valve's main knob—the one you turn to ignite the pilot. The adjustment controls how much gas flows to the pilot flame itself, making it burn larger or smaller. This is different from the main burner control; you're only changing the tiny flame that stays lit all the time, not the fire you see when you turn the fireplace on.
Before you touch anything, turn off the gas at the control valve by turning the knob to the "Off" position and wait two minutes. This is a safety step that lets any residual gas clear. You do not need to turn off gas at the meter—just at the fireplace valve. Once the pilot is off, you can safely access the adjustment screw or dial without risk of burns.
Key Takeaways
- The pilot light adjustment screw or dial sits on the gas control valve, usually near the main on-off knob, and controls only the size of the pilot flame.
- Turn the fireplace gas valve to "Off" and wait two minutes before making any adjustment to avoid burns or gas leaks.
- A healthy pilot flame is blue with a small yellow tip and should be about one-half inch tall; if it's too small or too large, the adjustment screw needs turning.
- Turn the adjustment screw clockwise to make the pilot smaller and counterclockwise to make it larger, then relight and observe the flame for one full minute.
- If the pilot won't stay lit after adjustment or the flame looks orange or sooty, the valve may need professional service rather than further adjustment.
Identifying whether your pilot needs adjustment
A properly adjusted pilot light burns steady and blue, with only a tiny yellow tip at the very top. The flame should be roughly one-half inch tall—about the height of a grain of rice standing on end. If your pilot is much smaller than that, it may struggle to stay lit or fail to heat the thermocouple (the safety device that keeps gas flowing). If it's much larger, it wastes gas and can overheat nearby parts.
Watch the pilot for a full minute after you light it. A flame that flickers constantly, goes out on its own, or produces a lot of orange or yellow color (rather than mostly blue) is a sign something needs adjustment. If the pilot lights fine but won't stay on when you release the igniter button, the flame is probably too small and needs to be turned up.
How to locate and turn the adjustment screw
Remove the fireplace front panel or trim ring so you can see the gas control valve clearly. On most units, this means unlatching two or four clips or removing a few screws—your fireplace manual will show you exactly where. Once the panel is off, look at the valve body itself. You should see a small screw (usually with a slot for a flathead screwdriver) or a small dial knob sticking out from the valve housing. This is your pilot adjustment.
The screw or dial will be labeled "Pilot" or have a small flame symbol next to it. Do not confuse it with the main on-off knob, which is much larger and turns to ignite the whole fireplace. If you cannot find a separate pilot adjustment, your fireplace may have a sealed valve that requires professional service to adjust. Some newer models do not allow owner adjustment for safety reasons.
Making the adjustment in small steps
Use a flathead screwdriver that fits the slot snugly—a screwdriver that is too small will slip and strip the screw. Turn the adjustment screw counterclockwise one-quarter turn to increase the pilot flame size, or clockwise one-quarter turn to decrease it. Do not make large turns; small adjustments are safer and let you see the effect clearly.
After each quarter-turn, turn the gas valve back to "Pilot" (or "On" if your valve has that setting) and light the pilot using the igniter button or a long lighter. Hold the igniter button down for 30 to 45 seconds to give the thermocouple time to heat up. Once the pilot stays lit on its own, observe it for a full minute. If the flame is still not the right size, turn the gas back to "Off," wait two minutes, and make another quarter-turn adjustment.
What the flame should look like after adjustment
After you adjust and relight, the pilot should burn with a steady, mostly blue flame about one-half inch tall. The very tip may show a small amount of yellow or orange, but the bulk of the flame should be blue. The flame should not flicker or dance around; it should hold its shape and size. If you see a lot of orange or yellow, or if the flame is sooty (leaving black marks on the surrounding metal), the adjustment may not be the problem—the valve itself may need cleaning or replacement.
Let the pilot burn for at least one full minute before you decide whether the adjustment worked. Pilot flames can take a moment to stabilize after you light them. If the flame goes out during this minute, the adjustment was not enough; turn off the gas, wait two minutes, and turn the screw counterclockwise another quarter-turn to make the flame larger.
When to stop adjusting and call a professional
If you have made three or four small adjustments and the pilot still won't stay lit, or if it burns orange and sooty no matter which way you turn the screw, the problem is likely not the adjustment itself. The thermocouple may be dirty or failing, the valve may have internal damage, or the gas line may have a blockage. These issues require a service technician with specialized tools.
Do not force the adjustment screw or turn it more than a full rotation in either direction. If you feel strong resistance, stop and contact a professional. Forcing the screw can damage the valve and create a gas leak. Similarly, if you smell gas at any point during adjustment, turn off the gas at the valve when ready, open windows, and call your gas company's emergency line.
Reassembling and testing the full fireplace
Once the pilot is adjusted and burning steadily, turn off the gas at the control valve and wait two minutes. Reinstall the front panel or trim ring by reversing the steps you used to remove it—usually latching clips or replacing screws. Make sure the panel sits flush and all clips or fasteners are tight.
Turn the gas back on at the control valve and test the full fireplace by turning the main knob to the "On" position. The pilot should light the main burner within a few seconds, and the fireplace should produce a full flame. Let it run for a few minutes and watch for any unusual behavior—flickering, delayed ignition, or the flame going out. If everything looks normal, your adjustment is complete. If the main burner still has problems, that is a separate issue from the pilot adjustment.
Frequently Asked Questions
Which direction do I turn the screw to make the pilot flame bigger?
Turn the adjustment screw counterclockwise to increase the pilot flame size. Remember: counterclockwise makes it bigger, clockwise makes it smaller. Make quarter-turn adjustments and relight between each one so you can see the change.
How long should I hold the igniter button when relighting the pilot?
Hold the igniter button down for 30 to 45 seconds after the pilot lights. This gives the thermocouple time to heat up and signal the valve to keep the gas flowing. If you release the button too soon, the pilot may go out once you let go.
What does a healthy pilot flame look like?
A healthy pilot is mostly blue with a small yellow or orange tip, about one-half inch tall, and burns steadily without flickering. If you see a lot of orange or yellow, or if the flame is sooty or dancing around, the adjustment may not be the solution.
Can I adjust the pilot light while the gas is on?
No. Always turn the gas valve to "Off" and wait two minutes before touching the adjustment screw. This prevents burns and gas leaks. You can turn the gas back on to test the pilot after each adjustment.
What if the pilot light still won't stay on after I adjust it?
If the pilot goes out even after you have made several small adjustments, the thermocouple, valve, or gas line may need professional service. Do not continue adjusting; contact a fireplace technician instead.