Troubleshooting / Fault Clearance - GEM 550 Installation, Operating, & Maintenance Instructions

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Troubleshooting / Fault clearance

Fault
Control medium escapes
from vent hole* in the
actuator cover (for control
function NO) or connector 2*
(for control function NC)
Control medium escapes
from leak detection hole*
Working medium escapes
from leak detection hole*
Valve doesn't open or
doesn't open fully
Valve leaks downstream
(doesn't close or doesn't
close fully)
Valve leaks between
actuator and valve body
Valve body connection to
piping leaks
Valve body leaks
* see chapter 20 "Sectional drawing and spare parts"
550
Possible cause
Control piston leaky
Spindle seal leaking
Gland packing faulty
Control pressure too low
Control medium not connected
Control piston or spindle sealing
leaky
Actuator spring faulty
(for control function NO)
Operating pressure too high
Foreign matter between seat seal
and seat (see sectional drawing)
Valve body leaky or damaged
Seat seal* faulty
Actuator spring faulty
(for control function NC)
Union nut loose
Gasket* faulty
Valve body / actuator damaged
Incorrect installation
Bolting / threaded connections loose
Sealing material faulty
Valve body leaks or is corroded
40 / 44
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
Disassemble 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 union nut
Check gasket and the respective sealing
surfaces for damage and replace parts if
necessary
Replace valve body / actuator
Check installation of valve body in piping
Tighten bolting / threaded connections
Replace sealing material
Check valve body for damage, replace valve
body if necessary