[Joe F]

I have an intermittent issue with my Burnham Series 2 gas boiler. Once in a while, the flame on the end burner burns in the burner tube rather than burning "above" the flame slots. I can tell when it happens, because it makes a whistling sound. If I blow hard on it, it goes back to normal. It seems to happen once a month or so. Trying to figure out what might cause this.

 

[how]

Anything that slows your gas flow below your flame speed can cause the gas to burn inside the burner.
A partially obstructed gas orifice for that burner is the usual cause.
The burner orifice needs to be probed and hopefully cleared with something soft enough to not make the brass orifice larger than it was originally.
A "u" shaped piece of soft bare copper electrical wire can sometimes do the job without needing to remove the burner for access.


Pipe dope or pipe scale can be addressed this way but if the cause if from dead baby spiders, more disassembly becomes necessary.
A pro would also verify that your boiler gas pressure downstream from your gas valve is adequate when all other gas appliances in the home are on.

 

[ben's plumbing]

yep start with removing burners and clean...

 

[Joe F]

I pulled and cleaned all the burners (I've done this every year since I've had the boiler) and also ran a pipe cleaner through the brass "jets". No sign of any debris or dirt. If it matters, the burner that has the issue is the first one in line. I guess I'll wait to see if it happens again.