172-65608MA-03 (RGDS) 5 Oct 2021
18
Item
Cause
Diagnostic
Remedy
Does not reach
desired steam
temperature
The PID set
values are
incorrect
Check the PID set values
Correct the PID set
values
The temperature
sensor is
malfunctioning
Check the temperature value
reading from the sensor and
compare with the temperature
gauge, if the electrical wiring and
signal are normal, then the
temperature sensor is
malfunctioning
Replace with a new
temperature sensor
Component(s)
inside the
pressure control
valve positioner
are broken
Check for abnormal sounds from
the positioner
Replace with a new
positioner
(Investigate whether
the valve aperture
changes frequently or
the ambient
temperature is too
high)
There is a
problem with the
input current of
the temperature
control valve
Check that a signal of 4
– 20 mA is
being received by the CV at the
connection terminals
Adjust the controller or
replace with a new
controller
Desuperheating
water pressure
is too low
Check whether there is a correct
steam pressure
Supply steam at the
correct pressure