Indoor unit shows E2 and evaporator coil ices up or unit stops cooling

Safety: Turn OFF power at the breaker before opening the indoor unit.

• Step 1 – Thaw the coil: If there is ice, turn the system OFF and let it thaw completely (can take several hours). Place towels under the unit to catch drips.
• Step 2 – Access the thermistor: Remove the front cover and filter. Remove the plastic shroud to expose the evaporator coil. Locate the small sensor clipped to the coil (usually near the middle).
• Step 3 – Check sensor position: Ensure the thermistor is firmly clipped to the coil surface and not hanging loose. Re-clip if needed and ensure good contact.
• Step 4 – Inspect wiring: Follow the sensor wires back to the indoor PCB. Look for cuts, pinched wires, or loose connectors. Reseat the connector on the PCB.
• Step 5 – Replace sensor if needed: If E2 returns, replace the evaporator temperature sensor (T1) with a Carrier-compatible thermistor. Mount it in the same location and route wires as original.
• Step 6 – PCB check: If a new sensor does not clear E2, the indoor PCB sensor circuit may be defective and should be replaced by a technician.