ErrorCodeDoctor
Daikin · Air Conditioner

Daikin Air Conditioner L4 error code

Difficulty: Medium · Cost: $0–$350 · Duration: 15–20m

The L4 error means your Daikin air conditioner detected that the inverter PCB's radiation fin temperature rose to an abnormal level. This is often caused by insufficient airflow around the outdoor unit or a defective fin thermistor. Make sure the outdoor unit has adequate clearance on all sides. If the error persists contact a qualified technician.

Common causes

  • Radiation fin temperature rose due to a short circuit in airflow around the outdoor unit
  • Fin thermistor is defective
  • Inverter compressor has a fault

How to fix it

  1. 1

    Turn off the air conditioner and allow the outdoor unit to cool down

  2. 2

    Check that the outdoor unit has adequate clearance on all sides for airflow — remove any objects, debris, or plants blocking the unit

  3. 3

    Make sure the outdoor unit is not in direct sun with no airflow

  4. 4

    Restart and check if L4 returns

  5. 5

    If L4 persists contact a qualified technician to inspect the inverter fin thermistor

Related Daikin Air Conditioner error codes

1

A0

An external protection device connected to the indoor unit has been activated

hard
2

A1

A fault was detected in the indoor unit PCB (control board)

hard
3

A3

The drain level control system has detected an abnormality — drain may be clogged

medium
4

A5

Freeze-up protection (cooling) or high pressure control (heating) has activated — check the air filter

easy