User guide

Series MV/F, MVM/F, MVP/F, MVMP/F Page 10
9510-050-en Revision 02
TM 7669 Edition 10/2009
8 Malfunctions

Flange connection valve/pipe is leaking
Retighten the flange screws to a tightening torque
according to Section 1.3
. If this does not remedy
the leak, the recommended torques may be
exceeded by 10%.
If this also fails to stop the leak, dismantle and
inspect the valve.
 Flange connection body / bonnet is leaking
Retighten the body screws to a tightening torque
according to Section 1.3
. If this does not remedy
the leak, the recommended torques may be
exceeded by 10%.

Safety stuffing box (option) leaks
Tighten packing nut until the leak has been elimi-
nated.
Then dismount the valve as quickly as possible
and repair.
 Diaphragm valve does not switch
Is the actuator being supplied with power?
Is a directional control valve connected correctly?
Is there any foreign matter in the diaphragm
valve?
Leak between stem/bonnet and handwheel
Diaphragm is defective. See Section 9.1
.
In the case of valves which were opened, the
diaphragm must always be replaced with a new
one.