
B-70315EN/02 APPENDIXG.INSTALLING GAS FITTINGS AND WATER FITTINGS
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G.1 GAS FITTINGS
G.1.1 Tightening a Fittings
(1) Cut the end face of the tube at right angles, then install a box nut,
back ferrule, and front ferrule on the tube as shown below. At
this time, pay attention to their directions.
(2) Insert the tube through the fittings all the way through, then
tighten the box nut until you feel a resistance with fingers. Next,
tighten the nut further by one and a quarter turns with a wrench.
Method of installing ferrules
(3) After the work above, mark the box nut and the main fittings as
shown in the figure.
G.1.2 Reinstalling a Fittings
(1) Before removing the tube, provide marks so that the positions of
the box nut and the main fittings can be identified.
(2) Remove the tube.
(3) When installing the tube, ensure that the mark on the box nut of
the fittings matches the position marked in step (1).
(4) If the same marked position is reached just by gently turning the
box nut by fingers, cut the tube area where the old ferrule was
installed, then install a new ferrule according to the procedure
described in Subsection G.1.1.