Panasonic CS-E7NKR Service Manual page 76

12.2.4.1 Cutting and flaring the piping
1 Please cut using pipe cutter and then remove the burrs.
2 Remove the burrs by using reamer. If burrs is not removed, gas leakage may be caused. Turn the piping end
down to avoid the metal powder entering the pipe.
3 Please make flare after inserting the flare nut onto the copper pipes.
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