dosatron SD25AL5 Manuel D'utilisation page 68

Changing the dosing assembly seals
(in the absence of pressure)
Frequency advised: Once a year.
Do not use metal tools or utensils
ADVICE: Before any dosing assembly is
disassembled it is recommended that the
DOSATRON be put into operation by suction of
clean water in order to rinse the injection system.
This prevents any risk of contact with products
that may be located in the dosing assembly.
N.B. Wear protective goggles and gloves during
any operation of this kind.
- Close the water inlet and reduce the pressure
to zero.
- Unscrew the upper bolt and disconnect the
monitoring module from the doser section by
pulling downwards.
- Push the monitoring module lid upwards and
remove the hydraulic body
- Check the state of the membrane in the
monitoring module
- Disassemble the hydraulic body valves
to change the suction seals and valves and
the corrugated tail (see § CLEANING AND
REASSEMBLING THE SUCTION VALVES)
- Unscrew the dosing assembly manually and
using a long, cross-tip screwdriver
- Pull downwards to remove the dosing assembly
- Replace the seals
Method for removing a seal
Changing the motor piston
(in the absence of pressure)
© ©
DOSATRON INTERNATIONAL S.A.S. / 32 DOSATRON INTERNATIONAL S.A.S. / 68
Pinch the part and the seal
between the thumb and
index finger; push it back
towards the opposite side
to deform it.
Accentuate the
deformation to take hold
of the section of the seal
which overlaps, then
remove the seal from its
bearing.
- Close the water inlet and
reduce the pressure to zero.
- Unscrew the dosing
assembly manually
- Pull downwards to remove
the dosing assembly
- Remove the flexible blade
switch sensor from the lid by a
quarter turn
- Unscrew the lid manually
and remove it.
Remove the motor piston unit
by pulling upwards.
- Install the new motor piston
and reassemble the doser
in the opposite order of the
disassembly.
- Manually reassemble the
original lid taking care not to
damage its seal.
- Insert the flexible blade
switch sensor unit in the centre
of the lid and lock it by a
quarter turn.