Aprilaire 1850F Installation And Operating Manual page 9

TROUBLESHOOTING
TABLE 1 – Diagnostic Codes (continued)
Diagnostic
Code Failure Mode
E7 Float Switch Open
E8 Inlet Air Temperature
Out of 50°F – 104°F
range, or dew point
below 40°F
TABLE 2 – Troubleshooting Guide
Symptom Possible Reason
Dehumidifier does not No power to unit.
turn on/run.
Dehumidifier blower is Pressure drop across dehumidifier
running but with little or is higher than 0.6"w.c.
no airflow.
Dehumidifier blower is Float switch open.
running but compressor
is not.
Coil frosting.
Inlet air temperature is outside of
the 50°F – 104°F range or the dew
point is below 40°F and there is a
demand for dehumidification.
Dehumidifier is not Drain line blocked or unit not level. • Verify that the unit is level.
draining properly.
Dehumidifier is Normal function.
producing hot air.
(CONTINUED)
Action
1. Empty the condensate pan.
2. Check the float switch connection at the control board.
3. If not using a float switch, verify jumper is between float switch terminals on dehumidifier
control board.
4. If the problem persists, replace the float switch.
1. If temperature is out of range, no action, normal operation.
2. If air temperature is between 50°F –104°F with a dewpoint above 40°F, contact Technical
Support.
Troubleshooting Procedure
• Check that the dehumidifier is plugged in.
• Check that the power switch is turned ON.
• Check that the control is turned ON.
• Check that the circuit breaker has not tripped.
• Check dehumidifier air filter and wash or replace.
• If float switch installed, check connections at control board and empty condensate pan.
• If no float switch installed check that the jumper is installed at the float switch terminals
on the control board.
• Lack of or reduced airflow. Check dehumidifier air filter and wash or replace.
• Check that there is nothing blocking the inlet or outlet of the dehumidifier.
• Inlet air conditions below 60°F. Increase the humidity setting.
• No action. The compressor will not run if inlet conditions are out of range.
• Check the drain line blockages and for a continuous downward slope.
• Air is reheated across the condenser coil, resulting in a temperature rise between inlet
and outlet.
Reset
Self-Correcting
Self-Correcting
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