Those tend to gall pretty bad. But all is not lost. Clamp the fitting in a vise and use a hack saw to cut a slot down the side of the fitting, Do not cut all the way across, you just want to cut to the threads, then split the nut and remove it. The critical area is the spot where the flare on the pipe sets so if you did cut into a few threads it will not be an issue.
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Friday, April 13th, 2018 AT 2:12 AM