Display shows E3, compressor does not start or stops shortly after starting.

Safety: Unplug the air conditioner. The condenser area contains hot components and the compressor; allow time to cool before working.

Steps:

• 1. Access rear/condenser section: For window and portable Danby units, remove the outer rear cover (several screws). Carefully lift off to expose the condenser coil (the hot coil at the back).
• 2. Locate condenser thermistor: Look for a small sensor clipped to the condenser tubing or fins, with two wires leading to the main PCB.
• 3. Inspect sensor and wiring: Check that the sensor is firmly attached to the coil and not hanging loose. Look for melted insulation, crushed wires, or corrosion at the connector.
• 4. Reseat connector: Disconnect the sensor plug from the PCB, inspect for moisture or corrosion, then reconnect firmly.
• 5. Test sensor: With a multimeter, measure resistance at room temperature and compare to expected NTC values or to another known-good sensor. If reading is open or shorted, replace the sensor.
• 6. Replace defective parts: Install a new Danby-compatible condenser thermistor if faulty. If the sensor tests good but E3 remains, the main control board may need replacement.

Do not bend or puncture the refrigerant tubing; this will permanently damage the unit.