Troubleshooting / Fault Clearance - Gemu 605 Installation, Operating And Maintenance Instruction

18

Troubleshooting / Fault clearance

Fault
Control medium escapes from
vent hole* of the actuator
Control medium escapes
from leak detection hole*
Working medium escapes
from leak detection hole*
Control medium escapes from
connector 4*
(for control function NC)
Control medium escapes from
connector 2*
(for control function NO)
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 19 "Sectional drawing and spare parts"
Possible cause
Actuator seal faulty
Spindle seal leaking
Valve diaphragm faulty
Piston seal faulty
Piston seal faulty
Control pressure too low
(for control function NC)
Pilot valve faulty (for control function
NC and control function DA)
Control medium not connected
Valve diaphragm incorrectly mounted
Actuator spring faulty
(for control function NO)
Piston seal faulty
(for control function NC)
Operating pressure too high
Control pressure too low (for control
function NO and control function DA)
Foreign matter between valve
diaphragm and valve body weir
Valve body weir leaking or damaged
Valve diaphragm faulty
Actuator spring faulty (for control NC)
Pilot valve faulty (for control function
NO and for control function DA)
Valve diaphragm incorrectly mounted
Bolting between valve body
and actuator loose
Valve diaphragm faulty
Actuator / valve body damaged
Incorrect installation
Bolting loose
Sealing material faulty
Valve body faulty or corroded
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Fault clearance
Replace actuator
Replace actuator and check
control medium for impurities
Check valve diaphragm for damage,
replace diaphragm if necessary
Replace actuator
Replace actuator
Operate valve with control pressure
specified in data sheet
Check and replace pilot valve
Connect control medium
Remove actuator, check diaphragm
mounting, replace if necessary
Replace actuator
Replace actuator
Operate valve with operating
pressure specified in data sheet
Operate valve with control pressure
specified in data sheet
Remove actuator, remove foreign
matter, check valve diaphragm
and valve body weir for damage
and replace if necessary
Check valve body weir for damage,
if necessary replace valve body
Check valve diaphragm for damage,
replace diaphragm if necessary
Replace actuator
Check and replace pilot valve
Remove actuator, check diaphragm
mounting, replace if necessary
Retighten bolting between
valve body and actuator
Check valve diaphragm for damage,
replace diaphragm if necessary
Replace actuator / valve body
Check installation of valve body in piping
Tighten bolting
Replace sealing material
Check valve body for damage,
replace valve body if necessary
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