Yellow flame in a gas grill can be a sign of failed components or simply an adjustment problem. This can cause low heat, uneven heat, a build up of soot on foods, and just general bad grilling.
Often the regulator on gas grills gets stuck. This causes low gas pressure. You will notice that your grill isn't getting hot. To fix a stuck regulator follow these steps exactly:
1. Turn off the gas at the propane tank
2. Disconnect the gas line from the tank
3. Open the grill lid
4. Turn all control valves to high
5. Wait for about a minute
6. Turn all control valves to off
7. Reconnect the gas line to the tank
8. SLOWLY turn on the gas at the tank
9. Light the grill normally
10. Your grill should now heat normally
To keep the regulator from sticking again make sure that you turn off the control valves first, then turn off the tank valve. Always open your tank valve slowly. If your gas grill still has yellow flame and the temperature is still low you will need to replace the regulator.
An improper air/propane mixture or a dirty burner:
1.Try adjusting the air vent behind the control knob on the gas grill to allow more or less air to be mixed with the propane and will generally result in a blue flame. (A blue flame with yellow tips is optimal for grilling.)
2.If adjusting the air vent yields no results,try to clean out the burner. Even brand new burners can be clogged, usually with dust or other particles from storage or transit.
A couple of blasts with an air compressor through the gas grill’s air vent should be enough flush out anything that may be clogging the burner.
3.If there is no air compressor handy a garden hose may be used instead.
Other checking for yellow flame and resolving methods:
1. First check the setting of the Venturi. This is the area on the burner(s) which allows air to mix with the gas. It may be open slightly and it may have a screen to prevent insects from getting inside. Too much or too little means yellow flame and less heat. Play with it when the grill is own (please be careful not to burn yourself, it may get warm or be close to the burners) and adjust it to see if you get a bluer flame.If this does not help,then
2. Check the orifice at the end of the gas line which attaches to the burner for spider webs or an obstruction. Clean it off with a q-tip just to be sure.For the third fix,
3. Turn the burner control valves completely off. Turn off the gas at the tank fitting. (this may already be that way). Remove the gas line with the regulator from the gas tank. The regulator is the round thing which attaches to the tank. Turn the burner control valves on to full and purge for at least a minute. Turn off the control valves. Reattach the regulator/gas line to the tank and slowly turn on the gas. Now turn on one of the burner control valves (generally one is marked to turn on to start) and start the grill. Now turn on remaining valves. Close the lid and let it run for 10 -1 15 minutes and see what the high temperature is.