No dehumidification, air mover runs but compressor does not.
1.Bad connection in compressor circuit
2.Safety float switch closed, check pump reservoir
3.Defective compressor capacitor
4.Defective compressor overload
5.Defective compressor
6.Defective control board
Air mover does not run. Compressor runs briefly but cycles on and off.
1.Loose connection in blower circuit
2.Obstruction prevents impeller rotation
3.Defective air mover
Unit removes some water but not as much as expected.
1. | Air temperature and/or humidity have dropped |
2. | Humidity meter and/or thermometer used are out of |
| calibration |
3. | Unit has entered defrost cycle |
4. | Air filter dirty |
5. | Defective defrost thermistor |
Compressor runs with POWER button OFF.
1.Defective relay
2.Defective control board
3.Upper housing not sealed to tower
No hour meter display when the HOURS button is pressed.
1.Unit is plugged in
2.Battery charge is low. Replace battery
3.Defective control board
5.3 Air Mover
The motorized impeller has a PSC motor and internal thermal overload protection. If defective, the complete assembly must be replaced.
1.Unplug power cord
2.Remove the four screws attaching the bottom plate to the lower housing
3.Disconnect the impeller leads
4.Remove the four screws holding the impeller to the bottom plate
5.Reassemble the new impeller using the above procedure in reverse
6. | Low refrigerant charge |
7. | Air leak such as loose cover |
8. | Defective compressor |
9. | Restrictive exhaust or inlet ducting |
Unit runs but does not pump water.
1. | Hose kinked or plugged |
2. | Pump motor defective |
5.4 Thermistor
The defrost thermistor is attached to the refrigerant suction line between
the accumulator and the evaporator.
To replace thermistor:
1.Unplug the dehumidifier
2.Remove the front housing
Figure 4: Thermistor attached to the refrigerant line.
3. | Pump check valve plugged |
4. | Bad connection in pump circuit |
5. | Hose disconnected internally |
6. | Defective control board (pump phase) |
Unit pumps water automatically but not when PURGE button is pushed.
1.Bad connection in PURGE button circuit
2.Defective control board
Evaporator coil frosted continuously, low dehumidifying capacity.
1.Defrost thermistor loose or defective
2.Low refrigerant charge
3.Dirty air filter or restricted air flow
4.Upper housing is not sealed to lower housing
3.Cut cable ties and remove aluminum tape.
4.Remove control panel
5.Unthread thermistor from control housing grommet
6.Detach thermistor from control board jumper, J1
7.Reassemble thermistor and dehumidifier using the above procedure in reverse
Figure 5: Picture of pump and reservoir.
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