Indoor unit shows E2 and stops; unit may start then shut down after a short time, especially in cooling mode.

Safety: Isolate power at the breaker before opening the indoor unit. Sharp metal fins can cut skin; wear gloves.

Steps:

• 1. Remove front cover: Open the front panel, remove filters, and remove screws to access the evaporator coil and control box.
• 2. Locate evaporator sensor: Look for a small probe-type NTC sensor clipped to the evaporator coil tubing, usually near the middle or outlet side, with two wires going to the PCB.
• 3. Check physical placement: Ensure the sensor is firmly clipped to the copper tube and not hanging loose. Re-clip it tightly to ensure good thermal contact.
• 4. Inspect wiring: Follow the sensor wires to the PCB. Check for cuts, pinches, or signs of overheating. Reseat the connector on the PCB.
• 5. Test resistance: With power OFF, disconnect the sensor and measure resistance. Compare to the room sensor value at similar temperature. If reading is open or near zero, replace the sensor.
• 6. Replace sensor: Obtain an Airwell-compatible evaporator NTC sensor. Remove the old sensor clip, install the new sensor in the same position, and route wires neatly. Plug into the same PCB connector.
• 7. PCB check: If the sensor is within spec and wiring is intact, the indoor PCB sensor input may be defective and require replacement.
• 8. Reassemble and test: Refit covers and filters, restore power, and run the unit. Confirm that E2 does not reappear.

Call a professional if PCB replacement is needed or if you cannot safely access the coil area.