Hardi AEON CENTURA TWIN FORCE Instruction Book page 171

2. Snapped together are the black plastic parts. To disassemble, insert
a flat screwdriver (B) and press, until the locking piece (A) snaps
out.
3. With the locking piece (B) removed, place the screwdriver as
shown and pull to remove the upper part (C) of the nozzle holder.
Here the separate locking piece (B) and the upper part (C).
4. Inside the lower part (D), the O-ring (E) is located.
5. Check condition and position of the O-ring. Replace, if damaged or
cracked.
÷
NOTE! When seated, the O-ring is supposed to be a little out of
shape when it fits tightly around the hole in the nozzle pipe.
6. If reused, clean the O-ring.
6 - Maintenance
171