Troubleshooting / Fault Clearance - GEM N082 Installation, Operating And Maintenance Instructions For The Installer And The User

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Troubleshooting / Fault clearance

Fault
Valve doesn't open or
doesn't open fully
Valve leaks downstream
(doesn't close or doesn't
close fully)
Valve leaks between
valve bonnet and valve
body
Valve body connection to
piping leaks
Valve body leaks
* see chapter 19 "Sectional drawings and spare parts"
N082, N182
Possible cause
Operating pressure too low
Diaphragm incorrectly mounted
Compression spring faulty
Operating pressure too high
Piston seal or seat seal leaking or
damaged
Diaphragm faulty
Compression spring faulty
Diaphragm incorrectly mounted
Bolting between valve body and
valve bonnet loose
Valve body / valve bonnet damaged
Incorrect installation
Threaded connections loose
Sealing material faulty
Valve body faulty
Fault clearance
Operate valve with operating pressure specifi ed
in data sheet
Remove valve bonnet, check diaphragm
mounting, replace if necessary
Replace compression spring
Operate valve with operating pressure specifi ed
in data sheet
Check piston seal and seat seal for potential
damage, replace piston seal or seat seal if
necessary
Check diaphragm for damage, replace
diaphragm if necessary
Replace compression spring
Remove valve bonnet, check diaphragm
mounting, replace if necessary
Retighten bolting between valve body and valve
bonnet
Replace valve body / valve bonnet
Check installation of valve body in piping
Tighten threaded connections
Replace sealing material
Check valve body for damage, replace valve
body if necessary
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