Went to a call that has been in operation for 10 plus years. Found some issues that I will get fixed, but one item I cannot find any info on is the air shutter adjustment for the main burner.

Found an old screwdriver in the bottom, plastic melted off the handle. Nobody worked on it since install, per homeowner. Also, the main burner air shutter bracket was removed and there in the bottom. It can slide open and closed and the bracket appears to only be a support for the orifice elbow.

I cannot find any info on the proper setting for propane. From past propane settings I think it is usually wide open. Just want to make sure.

Any info appreciated.