Sullair DEX Series - Section 6 TROUBLESHOOTING; Troubleshooting Guide

35
DEX HEATED REGENERATIVE DRYER
Section 6
TROUBLESHOOTING
Symptom Probable Cause Remedy
High humidity alarm (with
optional dew point monitor)
The regeneration of the desiccant
beds is insufficient.
Reset the alarm with the “Alarm Reset”
push button. Verify the heating and cooling
operations by observing regenerations. Are
the regeneration temperatures in
accordance with those listed in Section 3.7?
The dewpoint probe service valves
are closed.
Open the probe service valves.
Loss of power alarm The control circuit fuse has blown. Check the fuse and replace if necessary.
The PLC has failed or is in an
alarm condition.
Check the PLC to verify if any outputs are
“on” or if the PLC alarm LED is on. Replace
the PLC if necessary.
The system incoming power has
been lost.
Check the incoming power and restore the
supply.
Blower overload alarm The motor overload has operated. Check the motor overload to see if it is
defective. Check the operating conditions to
see if the motor is operating overloaded as
a result of a problem with the blower or
motor bearing, etc.
Vessel #1 De-pressurization
failure
The depressurization valve did not
open.
Check the solenoid valves for correct
operation. Check the valve actuator for
correct operation.
Vessel did not depressurize. Check if the depressurization muffler is
plugged.
Vessel depressurized but alarm is
on.
Check pressure switch for correct
operation.
Vessel #2 De-pressurization
failure
The depressurization valve did not
open.
Check the solenoid valve for correct
operation. Check the valve actuator for
correct operation.
Vessel did not depressurize. Check if the depressurization muffle is
plugged.
Vessel depressurized but alarm is
on.
Check pressure switch for correct
operation.
Vessel #1 Re-pressurization
failure
The repressurization valve did not
open.
Check the air actuated ball valve for correct
operation. Check the valve actuator for
correct operation and check the pilot
solenoid valve.
Vessel re-pressurized but the
alarm is on.
Check pressure switch PSH-1 for correct
operation.