TROUblESHOOTING
TAblE 7 – Green lED Codes
Activity
Status
Solid ON
Compressor ON
Blinking 1 sec . ON & 1 sec . OFF
Sampling
Blinking 1/2 sec . ON & 1/2 sec . OFF
Defrosting
Alternating Green & Red
Control knob was left in Test Mode
Technical Support is available Monday through Friday, 7:00 a .m . to 5:00 p .m . CST, at (800) 334-6011 . Use the guides on the following pages to
identify and correct system faults . Contact Technical Support before replacing the unit or components and for additional troubleshooting .
lED CODES
The dehumidifier control board uses the Status LED to communicate
current status or a fault code . Faults can be either critical or non-
critical . In either case, when a fault is detected, the red LED will flash
the fault code and all outputs will immediately turn off . A critical
fault can be cleared by repairing the fault
and
cycling power to the
dehumidifier . A non-critical fault will be cleared when the fault is
repaired . Cycling power is not required .
TAblE 8 – Red lED Codes
Number
of blinks
fault Type
failure Mode
failure Condition
Action
1
Non-Critical
Internal RH
sensor fault .
RH sensor open or shorted .
1 . Check connection between sensor board and control board .
2 . If connection okay, replace sensor board, Part No . 4752 .
2
Critical
Internal
temperature
sensor fault .
Temperature sensor open or shorted .
1 . Check connection between sensor board and control board .
2 . If connection okay, replace sensor board, Part No . 4752 .
3
Non-Critical
Model 76
Remote Control
fault .
Model 76
Remote Control
not
communicating with dehumidifier .
1 . Check connections between Model 76 and dehumidifier
control board .
2 . If connections are correct and secure, turn off the
dehumidifier and remove the Model 76 . Use a short section
of 4-wire cable to reconnect the Model 76 to the control
board . Turn the dehumidifier back on and increase the
dryness level setting on the Model 76 . If the dehumidifier
turns on, the problem is with the wiring between the
dehumidifier and control .
3 . If the dehumidifier does not turn on, call Technical Support .
4
Critical
Insufficient
capacity .
After 20 minutes of compressor operation,
the frost sensor temperature is not at least
5°F below the inlet air temperature .
1 . Check the frost sensor connection at the control board .
2 . Remove the side panel (when facing side of unit, on/off
switch will be on left) and verify the temperature sensor is
not damaged, is fully inserted in the sensor well, and the
well is filled with thermal paste .
3 . If the sensor is not damaged and positioned correctly,
contact Technical Support .
5
Non-Critical
Inlet air
temperature out
of range .
Internal temperature sensor reads out
of 50°F –105°F range for compressor
operation . NOTE: If compressor is on when
fault condition occurs, the compressor will
turn off . If the compressor is not on when
the fault condition occurs, there is no fault .
1 . Circulate air through the unit by setting the Cycle Period to
1 hour and Cycle Time to 60 minutes . After a minimum of
10 minutes, cycle power to the dehumidifier .
2 . If fault persists, call Technical Support .
6
Critical
Frost sensor
failure .
Frost temperature sensor open or shorted .
1 . Check the frost sensor connection at the control board .
2 . Remove the side panel (when facing side of unit, on/off
switch will be on left) and verify the temperature sensor is
not damaged, is fully inserted in the sensor well, and the
well is filled with thermal paste .
3 . If the fault persists, contact Technical Support .
7
Non-Critical
Float switch
open .
Open circuit between float switch inputs .
1 . Empty the condensate pan .
2 . Check the float switch connection at the control board .
3 . If not using float switch, verify jumper is between float
switch terminals on dehumidifier control board .
4 . If the problem persists, replace the float switch .
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