Absolutely dish detergents with chlorides corrode gas line metal! My lines were installed 5 years ago and the residue the plumbers’”soapy water test” left behind ate holes in the metal. It could have killed us. I replaced all lines this year at my own expense resulting from installers who didn’t stick to their training and assumed like all the websites that dish soap will be ok. It was not. Any plumber who uses soap will NEVER be hired my me. They are not paying attention to their safety training to be gas line certified. Florida Gas inspector said that 30% of all gas leaks are caused by detergent residues left on pipes.There is a reason the proper compounds are sold and they are trained to use them in their certification. My installer said the gas line test compound now comes with the fittings because the corrosion issue is so pervasive from plumbers refusing to buy it, now they have no excuse. Follow the science and prevent a tragedy down the road. Use Use what the gas company recommends not Joe Plumber who played on his phone during class.
