Maintenance And Trouble Shooting - Siata V230 Manual De Servicio

V230
E
9 MAINTENANCE AND TROUBLE
N
SHOOTING
G
L
Warning
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In case it is not differently specified in the below table any valve maintenance and/or
installation operation must be carried out in the absence of hydraulic pressure. For this
S
reason, disconnect the water delivery line to the valve.
H
Fault
Leaks to the drain
during service or
when in stand-by
2
Cause
Leak from pilot
Valve leak through the
piston /seals and spacer
system.
Corrective action
A) Twin pilot valve – before closing the inlet water sup-
ply disconnect the drain rubber tube and check if there is
leaking from that tube, in case there is, close inlet water
pressure and change the twin pilot assy.
B) External distributor valve – before closing the inlet water supply, disconnect the drain plastic tube from the
pilot distributor system. If there is a leakage from the
drain port one or more pilots must being replaced.
A pilot circuit leakage can cause also malfunctions of
the valve because the pressure can't be maintained on
the pressure chambers hence the piston of the valve
can be bad positioned. After the pilot leakage problem is
solved restore inlet water supply and put the controller
in service position to check if leakage has stopped, if no
maintenance is required on the valve.
If the water leaking from the drain is softened check for
damages on the outlet part of the valve, in particular
outlet piston / seals and spacers, otherwise check for
damages on the inlet part of the valve.
Dismount the pistons and the seals and spacer pack.
Visually check every item inside the valve and replace
the damaged part. If more that a third of the total o-ring
needs to be replaced change the complete piston + seals
and spacers sub-assy.
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