17 Information
Note on Directive 2014/34/EU
(ATEX Directive):
A supplement to Directive
2014/34/EU is included with the
product if it was ordered according
to ATEX.
18 Troubleshooting / Fault clearance
Fault
Medium escapes from leak
detection hole (see sectional
drawing chapter 19)
Valve doesn't open or
doesn't open fully
Valve leaks downstream
(doesn't close or doesn't
close fully)
Valve leaks between
bonnet and valve body
Valve body connection to
piping leaks
Valve body leaks
Handwheel cannot be
turned
Possible cause
Valve diaphragm faulty
Bonnet faulty
Valve diaphragm incorrectly mounted
Operating pressure too high
Foreign matter between valve
diaphragm and valve body weir
Valve body weir leaking or damaged
Valve diaphragm faulty
Valve diaphragm incorrectly mounted
Bolting between valve body and
bonnet loose
Valve diaphragm faulty
Valve body / bonnet damaged
Incorrect installation
Threaded connections / bolting loose
Sealing material faulty
Valve body faulty or corroded
Bonnet faulty
Handwheel clamp locked
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Note on staff training:
Please contact us at the address
on the last page for staff training
information.
Should there be any doubts or
misunderstandings in the preceding text,
the German version of this document is the
authoritative document!
Fault clearance
Check valve diaphragm for damage,
replace diaphragm if necessary
Replace bonnet
Remove bonnet, check diaphragm
mounting, replace if necessary
Operate valve with operating pressure
specifi ed in data sheet
Remove bonnet, 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
Remove bonnet, check diaphragm
mounting, replace if necessary
Retighten bolting between valve body and
bonnet
Check valve diaphragm for damage,
replace diaphragm if necessary
Replace valve body / bonnet
Check installation of valve body in piping
Tighten threaded connections / bolting
Replace sealing material
Check valve body for damage, replace
valve body if necessary
Replace bonnet
Unlock handwheel clamp
675