Troubleshooting Guide

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a. If applicable, disconnect the duct from the discharge of the dehumidifier. Verify that
the flap damper on the outlet of the dehumidifier opens/closes freely.
b. Verify that there is not a lengthy amount of ductwork (more than 50 feet) attached
to the inlet side, that the ductwork is free of obstructions and kinks and that the filter
is clean – remove the filter for this test if dirty.
c. Ensure all of the dehumidifier panels are in place and assembled with screws. DO
NOT REMOVE PANELS DURING THIS TEST.
d. Turn the ON/OFF toggle switch ON and have the mode set to OFF.
IMPORTANT: MAKE SURE THE AIR ENTERING THE DEHUMIDIFIER IS WARMER THAN 50°F
AND COOLER THAN 100°F TO GET USEFUL INFORMATION
e. Turn the mode to ON using the ON/OFF button. Lower the RH setting to as low as it
will go. The fan will run for three minutes and then the compressor will turn on.
f. After two minutes (one minute before the compressor turns on), press and hold the
MODE and UP buttons for three seconds then release. Use the UP or DOWN buttons
to scroll through the inlet air temperature (display shows value and “AIR
SAMPLING”), inlet air RH (display shows value and “% RH”) and suction line
temperature (display shows value only). The inlet air temperature and suction line
temperature should be within a few degrees of each other.
g. Perform the same series of button presses again after 15 minutes of compressor run
time to determine if the suction line temperature has dropped fifteen degrees (15°F)
or more. If the inlet air temperature is cold (i.e. around 60°F or below) or the air is
very humid (i.e. 60% or higher) the drop may be less than 15°F, but should be more
than 10°.
• If there is a temperature rise then the Frost Sensor and High Temperature
sensor have been reversed. Switch the connection on the internal power board.
• If there is no temperature drop then there is likely a refrigerant leak and the unit
will need to be replaced.
• If the temperature drop is 15° or more, than the reason for the E4 diagnostic
code was likely that there was a sudden change in environment or the unit was
cycled too quickly. The dehumidifier records the temperature of the suction line
just prior to the compressor starting, and compares this value to the suction line
temperature 20 minutes after the compressor has been running. If the initial
reading were artificially low, the difference between initial and final would also
be artificially low. During normal operation, the environment does not change
quickly enough for this to be an issue, but can be on initial installation or if
turning the unit on/off using the ON/OFF button to override normal time
between cycles.
On first installation, allow the dehumidifier to acclimate to the environment
before completing the installation. Use the ON/OFF button to turn the unit on.
Press the MODE and UP buttons to check the inlet air temperature, inlet air RH