Samson 3349, Mounting And Operating Instructions

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EB 8048-2 EN 8-1
Malfunctions
8 Malfunctions
Read hazard statements, warnings and caution notes in the 'Safety instructions and mea -
sures' section.
8.1 Troubleshooting
Malfunction Possible reasons Recommended action
Actuator and plug stem
does not move on
demand.
Actuator is blocked. Check attachment.
Remove the blockage.
WARNING! A blocked actuator or plug stem (e.g.
due to seizing up after remaining in the same
position for a long time) can suddenly start to move
uncontrollably. Injury to hands or fingers is possible
if they are inserted into the actuator or valve.
Before trying to unblock the actuator or plug stem,
disconnect and lock the pneumatic air supply as
well as the control signal. Before unblocking the
actuator, release any stored energy in the actuator
(e.g. spring compression). See associated actuator
documentation.
Diaphragm in the
actuator defective
See associated actuator documentation.
Signal pressure too low Check the signal pressure.
Check the signal pressure line for leakage.
Jolting movement of the
actuator and plug stem
Version with adjustable
packing
1)
: packing
tightened too far
Tighten the packing correctly (see information under
'Adjusting the packing' in the 'Installation' section >
'Testing the installed valve').
Actuator and plug stem
does not stroke through
the entire range.
Signal pressure too low Check the signal pressure.
Check the signal pressure line for leakage.
Plug has become
detached.
Fasten plug and plug stem together (see the
'Servicing' section).
Incorrect setting of
valve accessories
Check the settings of the valve accessories.
Increased flow through
closed valve (seat
leakage)
Dirt or other foreign
particles deposited
between the seat and
plug.
Shut off the section of the pipeline and flush the
valve.
Valve trim, particularly
with soft seat, is worn.
Replace plug (see the 'Servicing' section) or contact
our after-sales service.