Hi,

I recently replaced the thermocouple on my 3 year old hot water heater (the pilot light would not stay lit through an entire day) and am now seeing some yellow flame interspersed with the nice blue gas flame. I've seen other posts which mention that the burner might be dirty, but I don't believe there was any yellow before I changed the thermocouple and the burner is no dirtier now than before. My other thought is that air is mixed with the gas -- possible? I've done the soapy water test on both the burner gas supply and the pilot gas supply and they look good. Any suggestions? The thermocouple swap was very recent -- maybe just wait for any pollutants to work themselves out?

Thanks.

Why did you replace the thermocouple ?

Sometimes a draft will blow the pilot light out. Make sure the burner access covers are in place. Other possible causes are dirt in the gas line, loose thermocouple connections, or you have another defective thermocouple, the last thing will be you gas control valve see the pick the pic below,Thanks.

John

Yellow flame may indicate lack of oxygen entering burning chamber.