bernardc

If that's Gastite it's not installed correctly. The jacket should run all the way into the fitting with Gastite. Other CSST fittings don't have this feature. The hole is probably caused by chloride pitting corrosion to which stainless is vulnerable. Chloride is in sea salt, as in NaCl, sodium chloride, or table salt. If chlorides are present, either don't use CSST, use Gastite correctly, or wrap the ends in F4 tape.