Dehumidifier displays E1 and stops dehumidifying; fan may still run but compressor does not start.

Safety first: Unplug the dehumidifier before removing any panels. Capacitors near the compressor can hold a charge; avoid touching exposed terminals.

Steps to check and correct:

• Power reset: Unplug the unit for 5 minutes, then plug back in and see if E1 clears. If it returns, continue.
• Locate the room temperature sensor: On most Honeywell dehumidifiers, the ambient sensor is clipped near the air intake grille or on the evaporator coil bracket, connected by a small two‑wire harness to the control board.
• Inspect wiring: Check the sensor wires for cuts, pinches, or melted insulation. Ensure the connector is fully seated on the control board and free of corrosion.
• Check sensor placement: Make sure the sensor bulb is not dangling into the water bucket or pressed directly against the hot condenser coil; reposition it to its original clip on the evaporator or intake area.
• Test or replace sensor: If you have a multimeter, measure resistance across the sensor leads and compare to Honeywell’s temperature/resistance chart (typically a 10k NTC thermistor). If readings are open, shorted, or far off spec, replace the sensor.
• Control board check: If a known-good sensor is installed and wiring is intact but E1 persists, the main control board sensor circuit is likely faulty and the board should be replaced.

When to stop: If you are not comfortable testing live circuits or removing the front panel, contact a qualified technician.