English 5.906-565.0 Rev. 00 (12/12)
23
1 Sleeve
2 Leakage boring
Unscrew the sleeve (wrench size 21 mm).
Note:
If water leaks from the leakage boring during opera-
tion, the entire mechanics of the pressure switch
must be replaced.
Remove and clean the piston and spring.
Note:
The disc and gasket shown in the illustration some-
times remain in the sleeve during the disassembly. If
this is the case, they must not be removed for instal-
lation.
Grease the skirt and the O-ring of the piston
(grease 6.288-079).
Reinstall the mechanics of the pressure switch.
Dismount cylinder head (see "Dismounting the
cylinder head").
Pull the low pressure gaskets off the piston (see
"Replacing high and low pressure gaskets/replac-
ing low pressure gaskets").
Loosen screws.
Caution
Risk of damage. Do not directly touch the ceramic
piston with pliers. If a tool is required for removal, use
a piece of hose for protection.
Pull off ceramic piston.
Attach new ceramic piston.
Apply soluble screw securing adhesive to the
screw or use a new screw with securing coating.
Insert and tighten the screw (torque 9...11 Nm).
7.13 Check / replace the mechanics of the
pressure switch
7.14 Replacing the ceramic piston
