Linda: I am not a gas forge expert. I have a NC gas forge that has never been anything but hot when I ran the pressure up. Never any leakage of flame.

What I did not hear at all in your request was any indication of gas pressure that you are using. Do you have a pressure gauge? What did it show when you were experiencing problems? If three burners are operating and three are not, could there be a blockage? A ceramic tube is used in shielding thermocouple wires. Have you been using a thermocouple?

Once I had a problem with the burners on my barbeque grill. Over a long down period spiders had built webs that restricted gas or air flow. Compressed air solved the problem.

Hope your problem is soon solved. John