User guide

6-10 l Troubleshooting
Problem
Regeneration High
Temperature – If the regener-
ation temperature exceeds the
high temperature limit for the
specified time. Default values
are 400°F {204°C} for 20 sec-
onds.
Regeneration Temperature
Loop Break – The regenera-
tion temperature is outside of
the operator entered deviation
alarm band (see Regeneration
Temperature Deviation passive
alarm) and the regeneration
temperature is not moving
towards the setpoint at a rate
greater than specified. Default
values are 2°F {1°C} over 40
seconds.
Process Dewpoint – The
dewpoint has not fallen below
the setpoint. If the dewpoint
goes below the setpoint for
180 seconds the alarm should
go away.
NOTE: The alarm is not
active for the first 5
minutes.
Possible cause
One of the solid state relays (SSRs)
failed in the closed position.
The output on the board has failed.
The regeneration heater has failed.
The regeneration RTD is loose or has
fallen out.
The regeneration blower is not running.
The output on the control board has
failed or the fuse is blown.
Defective dewpoint sensor.
The hose or wiring connections to the
sensor block are loose or have fallen off.
Poor regeneration air flow.
The desiccant wheel may be contaminat-
ed.
Desiccant wheel not turning.
Leaks in the process air stream.
Power Purge blower not running.
Solution
Replace the failed solid state relays
(SSRs).
Replace the board.
Check the heater fuses, and resistance
across each leg of the process heater.
Check the regeneration RTD and tighten
if needed.
Check wiring or replace regeneration
blower.
Replace the control board or fuse.
Replace the sensor.
Check wiring and hose connections to
the sensor, resecure if needed.
Remove the air flow restrictions, dirty
filters, etc.
Check the desiccant for contamination,
replace if needed. Install plasticizer /
volatile trap for severe situations.
Replace the desiccant wheel.
See
Troubleshooting section entitled,
Replacing the desiccant wheel
.
See Troubleshooting section entitled,
Passive alarms, Wheel rotation alarm.
Check for worn or loose hoses.
Check fuses, wiring or replace blower.
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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.
✐