52
53
Problem
Cause
Checks
Action
NB
Pressure
difference
Meas-
ure flow
rates and
pressure
difference
Temperature
Compare
these
values to
the PSHE’s
thermo-
technical
data sheet
Liquid flow
Check pump
operation
Change
pump
Very poor
performance
and low
pressure
difference
Flow director
damaged
by pressure
shock or
unsuitable
process fluid
Check the
information
on the name
plate: are the
temperature,
and liquids
correct?
Check the
process
data if it is
available
Contact the
manufac-
turer
Problem
Cause
Checks
Action
NB!
Internal leak
(fluid mix)
Plate
cracked due
to water
hammer
or thermal
shock
Check that
plate side
liquid is
visible on
shell side
(leaking fluid
will be visible
on the outlet
pipe)
Contact
Vahterus
Hole in
plate due to
corrosion
Close plate
or shell side
valves and
use a metre
to see if the
pressure is
falling
Problem
Cause
Checks
Action
NB
External
leakage
between
cover plate
and flange
(openable
model)
Leaking
gasket
Look for leak
Tighten
bolts. If
retightening
does not
stop the
leak, remove
cover plate
and change
gasket
The Tech-
nical Data
sheet
contains
details of the
gasket. See
tightening
torque in
section 5.3.4
