You are correct. A yellow flame indicates an excessive amount of fuel is being allowed to escape from the gas nib (commonly called a gas jet). As these units usually do not have an adjustment for the pilot flame size it is the job of the nib to restrict the gas to the proper amount. If during a cleaning the nib it poked with a wire brush it opens it too much and this results in a large yellow flame. Other than that the nib may need to be changed out if the unit has been converted to LPG from LNG.
If your concern is the main burner flame then it is not getting enough air and needs to have the air adjust slider moved to allow more air to be mixed with the fuel. This is accomplished by finding the mix window and moving it further open. This will be a small piece of metal that is secured to the main gas inlet tube going from the gas valve to the main burner. It will be secured by a single screw. Loosen that screw and open the gap wider untill you get a flame that is blue at the base with just a tiny tip of yellow at the top.
Please post any other concerns you may have here.
Best regards, XXXXX XXXXX Smithy
Oh I see That doesnt sound good at all.
Here is a basic diagram. Are you saying the flames are coming out like the red in the drawing?
I would think that the burner has just been bumped, and is not aligned properly, or something is blocking the gas from entering the burner. If you can, reach into the top of the burner and see if something is blocking the gas from up top. Wear some surgeons type gloves as it is very possible that the problem is a large bug or small rodent. If your squeemish about such things then see if there is a handyperson, or maybe a college age kid in your neighborhood that can have a look at this for you. Im sure it is only a matter of a simple blockage. That is about the only thing that would cause this situation to occure in a short time frame.
Let me know if you need further assistance.
Ok, thats great.
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