Troubleshooting / Fault Clearance - Gemü 514 Originalbetriebsanleitung

19

Troubleshooting / Fault clearance

Fault
Control medium escapes
from vent hole (connector 4*
for control function 1 (NC) /
connector 2* for control
function 2 (NO))
Control medium escapes
from leak detection hole*
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 drawings and spare parts"
514_us
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 2, normally open (NO))
Operating pressure too high
Foreign matter between seat seal*
and seat
Valve body leaky or damaged
Seat seal* faulty
Actuator spring faulty (for control
function 1, normally closed (NC))
Union nut* loose
Gasket* faulty
Valve body damaged
Incorrect installation
Valve body leaks or is corroded
34 / 40
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
specifi ed in data sheet
Remove actuator, remove foreign matter,
check seat seal for damage and replace if
necessary (replacement of the steel seat
seal only by GEMÜ)
Check valve body and replace if necessary
Check seat seal for damage and replace if
necessary (replacement of the steel seat
seal only by GEMÜ)
Replace actuator
Retighten union nut
Check gasket and the respective sealing
surfaces for damage and replace parts if
necessary
Replace valve body
Check installation of valve body in piping
Check valve body for damage, replace valve
body if necessary