Since the invention and popular use of the gas barbecue, many urban myths have flourished and been popularized by rare but widely publicized stories of explosions, fires, and injuries. Every time my barbecue ‘set back’, my wife runs inside convinced that the barbecue is about to explode and takes half of our apartment block.
Recoil? For gas barbecues and many other gas stoves, they operate with little to no noise, yet occasionally a loud “pop” is heard before the sound of gas running like a torch. If you look under your grill, you will see that the flame from your gas burner has migrated from a quiet and quiet combustion from the correct openings along or above the flame ring or “burner” as some may call it; to a violent torch such as a flame originating from the gas-air mixing chamber where the gas connection first connects to the flame ring or burner. This is the point where my wife takes her emergency exit and heads for the hills, despite my assurances.
Here is the common mistake. The gas flame, for some reason, was transferred to the mixing chamber and because it now resembles a flamethrower, the natural and uninformed opinion is that the flame will now reignite within the LPG hose in the gas cylinder. LPG causing catastrophic explosion worthy of CNN helicopter news coverage and response from four fire trucks.
No, he will not. Two things prevent that from happening. First of all, there is a net gas leakage from your cylinder, which is why improperly burning flame sounds so fierce. Second, inside the gas hose there is alone gas (LPG); there is no air. LPG is flammable between 2% and 9% concentration in air. That is a very narrow flammability range. Have you ever tried lighting the gas burner on top of the stove and it seems like the gas is pouring out at an alarming rate and the stove piezo clicks and sparks, but the gas still won’t light? That’s because the gas is too rich to burn. The same goes for your gas hose that connects your gas cylinder to your gas barbecue.
So what should I do? Calmly determine which of the burners under the grill is the problem burner and turn it off. You will hear the same “pop” noise when the flame is extinguished now that the gas has stopped flowing. Then turn the gas back on and light the burner in the usual way and continue cooking your lunch or dinner. Oh, you may also have to go find your wife or friends from wherever they are hiding and assure them that dinner is served.