If some of the gas burners won't stay lit then it is likely that they are partially blocked with food debris or a buildup of other grime. If all of the gas burners won't stay lit then it is more likely that the air-gas mix is poor and needs to be adjusted. These gas stoves should be serviced regularly.
If your burner lights for a short time but then goes out, you may have a blockage in the gas valve. The gas line is what provides fuel to the burner to keep it lit.
The Thermocouple Is Defective
The thermocouple is responsible for sensing the flame of a gas stove. When it is defective, the stove may still start like normal but will then go off once you release the knob.
Ensure that the burner head and cap are properly aligned and seated. If they are askew, this could affect the flame. Clean the burner: Food debris, spills, or a clogged burner port can cause an uneven flame. Use a metal pin or a needle to gently clear out the holes on the burner where the gas comes out.
One of the most common causes for weak or uneven flames on your gas cooktop is because the burner head has grown dirty. When multiple holes on the burner head become blocked or even partially blocked, your gas cooktop will become slower to light and you will likely get weaker flames.
So you've checked your pilot light and even reset it, but still, it wont stay lit. This can be an indication that your fireplace thermocouple is either bad or worn out. However, if your pilot is lit but the gas fireplace isn't, then there's probably a problem with your thermopile.
Explanation: The most likely cause of flames that are lifting off the burner is improper air to gas mixture. Stoves work on the principle of combustion, and for efficient combustion, a proper mix of air (oxygen) and gas is necessary.
While every stove is different, you can expect a gas stove to last about 10 to 15 years on average. According to some sources, gas stoves tend to last longer than their electric or induction counterparts, though these options do have their own benefits that might be worth the trade-off.
Your gas fireplace could be turning off for several reasons. The most like culprits are likely tied to some kind of problem with your setup. Anything from issues with your pilot light, clogged ports on burners, damage to heating components, and thermocouple/thermopile malfunctions can be to blame.
While the most common causes of log burners going out are insufficient oxygen, fuel or heat, stoves also rely on a properly functioning chimney. The purpose of this is to draw out exhaust fumes that could suffocate your fire.
Low gas pressure or a faulty gas valve can interrupt the gas supply, causing the fire to burn out. If you can smell gas near the fire, hear hissing sounds, or the gas leak detectors activate, you must contact a professional right away to check for safety.
The gas burners may have developed a layer of dust and dirt, or a build-up of carbon, that makes it difficult for them to access the oxygen needed to light and stay lit. (This is one of the reasons you have a filter to protect the furnace's interior.)
There are many possible reasons why the burner will not stay lit - the gas jet may be blocked, the valve may be set too low, the air flow may be restricted, there may be an issue with the pilot light, and so on.
It's easy to replace, and a new one costs $5 to $10. Rather than trying to unfasten the thermocouple inside the water heater's burning chamber, it's easier to remove the whole burner and thermocouple assembly.
Ensure the Heat Pin is inside the flame when stove is lit. This can be moved by hand only when stove is cold. Pull the Heat Pin upwards to fix the issue. Ensure the Heat Pin is clean.
There's really just one telltale sign of letting you know when the thermocouple isn't working, and that's when the pilot light won't stay lit. If you experience this problem, it's important to have your thermocouple assessed as soon as possible.
Wipe down all sides of the burner caps with a non-abrasive scrubbing pad or cloth and mildly abrasive cleaner or soap. If the caps are extra dirty, soak them in hot, soapy water for a minimum of 20 minutes.
Inadequate Air Supply: Gas burners need oxygen to fuel properly. If there is low air to maintain combustion in the cooking area, or if the burners and vents are blocked with particles, the flame's power decreases.
Gas surface burners are often slow to light or will not light at all because the burner or burners are wet or dirty, the electrode is not seated properly or the burner head and cap are not matched up properly.
The normal cure for lifting flames is the reduction of primary air input to the burner. Gradually close the burner's air shutter until the problem does not occur.
Lifting burner flames result when the flow velocity of the gas/air mixture from a burner port is greater than the flame burning speed. The flame cannot stabilize on or just slightly above the burner port, as in normal operation.