Fault Table - HEROSE 0681X Notice D'utilisation

7.3

Fault table

Fault
 Safety valve does
not respond
Not liftable

 Leak in the
seating
 Damage to the
inlet/outlet
 Shock waves
 Constantly
blowing off
 Chattering
 Inadequate
capacity
22
Operating instructions
Cause
Covers have not been
removed;
Test pressure too high;
Back pressure not taken into
account;
Pressure below 85% of the set
pressure;
Foreign bodies between cone
and seating, contaminated
medium;
Seating damaged;
Cone seal damaged;
Safety valve has chattered;
Transport damage;
Wrong connecting thread /
tightening torque too high;
Impermissible forces such as
bending or torsional forces are
being transmitted;
Safety valve not mounted at
the highest point;
water not drained correctly or
at all;
Spring corroded by
impermissible medium and
broken;
System pressure too high
Seal damaged;
Pressure drop in the inlet line
>3%;
Seals for inlet and outlet
connector too small or not
installed centrally;
Safety valves are too powerful;
Outlet line too long or diameter
too small;
Inlet or outlet connector too
small;
Back pressure higher than 3%;
Safety valves dimensioned
incorrectly for the plant
conditions;
Safety valves not being used in
accordance with the applicable
regulations;
Phone +49 4531 509-0
Remedial action
 Remove covers.
 Replace the safety valve.
 Replace the safety valve.

Lifting in the range ≥85 % of the set
pressure without aids.
 Remove foreign bodies by briefly
lifting / flush the system or replace
the safety valve.

Replace the safety valve.

Replace the safety valve.

See "Chattering".

Replace the safety valve.
 Replace the safety valve.
 Install stress-free.
 Install the safety valve at the
highest point.
 Attach water drain according to
regulations.
 Replace the safety valve.

Replace the safety valve.
 Replace the safety valve.

Reduce resistance through chamfer
or radius in the connecting socket;
choose a larger one if necessary.
 Shorter inlet line.

Incorrect safety valve; exchange it.
 Change conditions.
 choose smaller safety valves.

Use a larger nominal diameter or a
back-pressure-compensating
stainless steel bellows. The max.
height is to be specified by the
manufacturer.

Dimensions must be larger than the
nominal inlet or outlet diameter.

Use back-pressure-compensating
stainless steel bellows. The max.
height is to be specified by the
manufacturer.
 Re-dimension and replace the
safety valve.
 Change conditions.