Daikin Chiller

Daikin Chiller Error Code L4

Troubleshooting guide for the Daikin Chiller system fault L4.

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What It Means

Malfunction of inverter radiation fin temperature rise.

Possible Causes

  • Fin temperature rise due to short circuit.
  • Defective fin thermistor.

Not sure which one it is — or if it's none of these? Try ACLogics today.

Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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Full Diagnosis

Malfunction of inverter radiation fin temperature rise

All Recorded Causes

Fin temperature rise due to short circuit Defective fin thermistor

Verify Before Replacing Parts

  1. Confirm the exact Daikin model family and chiller context before acting on a generic code description.
  2. Confirm board LEDs, wiring polarity, and model compatibility before replacing control boards — this Daikin fault points at fin temperature rise due to short circuit.
  3. Check for intermittent communication faults caused by connectors, moisture, or damaged harnesses, and rule out defective fin thermistor.
  4. After the correction, run the system long enough to confirm the chiller fault does not return under normal load.

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