Why does the flame lift off the burner or seem to float?
A flame that lifts off the ports or seems to float above the burner means the gas is coming out too fast for the burner — typically over-pressure, an air shutter open too far, or the wrong orifice for your fuel. It can also be a blower blowing across it. It's a combustion setup issue that needs a licensed tech to re-tune.
What "lifting" actually tells you
A flame anchors to the burner ports when gas velocity and air are in balance. When the flame detaches — floating above the ports, flickering blue at the base, sometimes with a faint roar — the gas is exiting faster than the flame can hold onto, or there's too much primary air. In plain terms, the burner is being over-driven. Left alone it can burn noisily, run inefficiently, and even lift far enough to blow itself out.
The setup causes
The common reasons we find: inlet pressure set too high, an air shutter or venturi opened too far, or — the big one — an orifice that doesn't match the fuel. A burner fitted for natural gas but fed propane (or a conversion done without the correct kit) delivers the wrong gas velocity and pressure, and lifting flames are a classic result. Propane runs at higher pressure and needs its own orifices, which is exactly why NG-to-LP conversions are licensed work and not a DIY swap. A blower aimed across the burner can also lift a flame that's otherwise fine.
Why this one isn't a wait-and-see
Lifting flames mean the air-fuel balance is off, and that's worth correcting promptly — both for proper, quiet operation and to keep combustion clean. We verify gas pressure, reset the air shutter, and confirm the orifice matches your fuel, all inside the sealed gas system we're licensed to service. If it started right after a conversion or a service call, that's usually where the answer is. Call (828) 545-0525.
How we can help
Related questions
- Why are my gas fireplace flames blue instead of yellow?
- Why does my gas fireplace burn differently after being converted between natural gas and propane?
- Why are my gas fireplace flames suddenly too tall?
- Why does my gas fireplace roar or sound louder than it used to?
- Why does my gas fireplace make a boom or loud whoosh when it ignites?
- Why won't my gas fireplace turn on at all?
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