Troubleshooting / Fault Clearance - Gemü 536 Original Einbau- Und Montageanleitung

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Troubleshooting / Fault clearance

Fault
Control medium escapes
from vent hole (connector
4* for control function NC /
connector 2* for control
function NO)
Control medium escapes
from actuator spindle*
Medium escapes at union
nut*
Valve doesn't open or
doesn't open fully
Valve leaks downstream
(doesn't close or doesn't
close fully)
Valve leaks between
actuator flange* and valve
body flange*
Valve body connection to
piping leaks
Valve body leaks
* see chapter 20 "Sectional drawing and spare parts"
536
Possible cause
Actuator membrane* leaking
Spindle seal leaking
Gland packing faulty
Control pressure too low
Control medium not connected
Actuator membrane* or spindle seal
leaking
Actuator spring faulty
(for control function NO)
Operating pressure too high
Foreign matter between seat seal*
and seat
Valve body leaks or is damaged
Seat seal* faulty
Actuator spring faulty
(for control function NC)
Hexagon nuts* loose
Gasket* faulty
Incorrect installation
Valve body leaks or is corroded
Fault clearance
Replace actuator and check control medium for
impurities
Replace actuator and check control medium for
impurities
Replace actuator
Set control pressure in accordance with data
sheet.
Check pilot valve and replace if necessary
Connect control medium
Replace actuator and check control medium for
impurities
Replace actuator
Operate valve with operating pressure specified
in data sheet
Remove actuator, remove foreign matter, check
seat seal for damage and replace if necessary
Check valve body and replace if necessary
Check seat seal for damage and replace if
necessary
Replace actuator
Retighten hexagon nuts*
Check gasket and the respective sealing
surfaces for damage and replace parts if
necessary
Check installation of valve body in piping
Check valve body for damage, replace valve
body if necessary
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