User guide

6-6 l Troubleshooting
Alarms
• Shutdown (A#): The dryer has automatically shut down because it has detect-
ed a serious problem that could damage your material or dryer.
• Passive (P#): The dryer continues to operate, but warns of a problem that could
prevent correct drying of your material. If ignored, this problem could lead to a
condition that will shut down the dryer.
Problem
A7 - Return Air High
Temperature – If the return
air temperature at the inlet to
the blower is greater than
180°F {82°C}, it shuts down
the dryer. (The return air tem-
perature 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
temperature is measured at
the inlet to the process blow-
er.)
A23 & P3 - Regeneration
Temperature Deviation – The
regeneration temperature
exceeds the deviation band for
the specified time. Default
values are 10°F {6°C} for 5
seconds.
Possible cause
The hopper does not contain enough
material.
You are drying at a high drying tempera-
ture above 120°F {49°C} or you are
running at low throughputs.
The aftercooler/intercooler does not
have enough water.
The aftercooler/intercooler coils are
dirty.
One of the solid state relays (SSRs) failed
in the closed position.
The heater has become defective.
The regeneration RTD is loose or has
fallen out.
The air hose connections are loose.
The output on the board has failed.
Solution
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 coils. See
Maintenance section entitled, Cleaning
the aftercooler/intercooler coils.
Replace the failed solid state relays
(SSRs).
Check the heater fuses and resistance
across each leg of the regeneration
heater
Check the regeneration RTD and tighten
if needed.
Tighten all air hose connections.
Replace the board.