Alarm Message Cause Corrective Action Dryer Status
Check the pressure setting
of the filter pressure
differential switch against the
print. Adjust accordingly.
DIRTY FILTER
The filter pressure
differential switch has
tripped.
Check the filter pressure
differential switch to make
sure it is functioning.
Replace is necessary.
- Dryer Normal :
- Process blower ON.
- Process heaters ON.
- Regen heaters ON.
- Alarm Message ON.
- Alarm horn is OFF.
VALVE MOTOR
FAIL
The limit switch on the
valve may not have
been wired correctly.
The switch is indicating the
incorrect desiccant tank is in
regeneration. Check the
wiring of the switch against
the wiring diagram. Make
sure all the wire connections
are tight.
- Dryer Shuts Down :
- Process blower OFF.
- Process heaters OFF.
- Regen heaters OFF.
- Alarm Message ON.
- Alarm horn is ON.
The return air temperature
thermocouple is not
connected to the
temperature controller. Make
sure the connections are
correct and tight.
P RETURN
SENSOR FAIL
The return air
temperature
thermocouple is open
or failed.
The return air temperature
thermocouple is damaged.
Replace the thermocouple.
- Dryer Normal :
- Process blower ON.
- Process heaters ON.
- Regen heaters ON.
- Alarm Message ON.
- Alarm horn is OFF.
Make sure the process air
filter is clean. Clean or
replace if necessary.
Make sure all the hose
connections are tight.
The process heater
contactor has failed in the
closed position. Check
heater contactor, replace if
necessary.
PROCESS
TEMP SAFETY
The high temperature
snap switch of the
process heater box
has tripped.
Check the high temperature
snap switch, replace if
necessary.
- Dryer Shuts Down :
- Process blower OFF.
- Process heaters OFF.
- Regen heaters OFF.
- Alarm Message ON.
- Alarm horn is ON.
Make sure the process air
filter is clean. Clean or
replace if necessary.
Make sure all the hose
connections are tight.
The Regeneration heater
contactor has failed in the
closed position. Check
heater contactor, replace if
necessary.
REGEN TEMP
SAFETY
The high temperature
snap switch on of the
regeneration heater
boxes has tripped
Check the high temperature
snap switches, replace if
necessary.
- Dryer Shuts Down :
- Process blower OFF.
- Process heaters OFF.
- Regen heaters OFF.
- Alarm Message ON.
- Alarm horn is ON.
Portable Drying/Conveying Systems Chapter 6: Troubleshooting 53 of 63