User guide

Troubleshooting l 6-9
6
Troubleshooting
Passive Alarms
If the amber Acknowledge Alarm LED is blinking, the alarm is a passive
alarm. The dryer continues to operate, but this problem could prevent cor-
rect drying of your material. Note that once the Acknowledge Alarm button
is pressed once, the blinking amber LED becomes solid.
NOTE: Passive alarms can be configured as shutdown alarms (see the previous
Shut Down Alarms section). See page 4-22, screen 59 for instructions.
Problem
Regeneration Temperature
Deviation – The regeneration
temperature exceeds the
deviation band for the speci-
fied time. Default values are
10°F {6°C} for 5 seconds.
Return Air Mid-High
Temperature – If the return
air temperature is between 150
and 180°F {66 and 82°C}.
(The return air tempera-
ture on W1600-5000 dry-
ers is measured at the inlet
to the desiccant wheel.
W1600-5000 dryers
designed prior to August
2007, the return air tem-
perature is measured at
the inlet to the process
blower.)
Regeneration Low
Temperature – The regenera-
tion temperature is less than
the low temperature setpoint
for the specified time.
Defaults are 200°F {93°C} for
20 seconds.
Possible cause
One of the solid state relays (SSRs)
failed.
The regeneration RTD is loose or has
fallen out.
The air hose connections are loose.
The output on the board has failed.
Defective regeneration heater.
The hopper does not contain enough
material.
You are drying at a high drying
temperature above 120°F {49°C} or run-
ning at low throughputs.
The aftercooler/intercooler does not have
enough water.
The aftercooler/intercooler coils are
dirty.
The regeneration heater has failed.
The output on the control board has
failed or the fuse has blown.
The regeneration RTD is loose or has
fallen out.
Solution
Replace the failed solid state relays
(SSRs).
Check the regeneration RTD and tighten
if needed.
Tighten all air hose connections.
Replace the board.
Check the heater fuses and resistance
across each leg of the regeneration
heater.
Make sure your material supply system
is working properly.
Ensure water flow to the aftercooler/
intercooler.
Turn on the water supply, or fix any
leaks or blockages.
Clean the aftercooler/intercooler coils.
See Maintenance section entitled,
Cleaning the aftercooler/intercooler
coils.
Check the heater fuses, and resistance
across each leg of the process heater.
Replace the control board or the fuse.
Check the regeneration RTD and tighten
if needed.
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