Daikin Chiller

Daikin Chiller Error Code P3

Troubleshooting guide for the Daikin Chiller system fault P3.

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What It Means

Malfunction of thermistor in switch box.

Possible Causes

  • Defective connection of thermistor.
  • Defective reactor thermistor.
  • Defective inverter PCB.

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 thermistor in switch box

All Recorded Causes

Defective connection of thermistor Defective reactor thermistor Defective inverter PCB

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 defective connection of thermistor.
  3. Check for intermittent communication faults caused by connectors, moisture, or damaged harnesses, and rule out defective reactor 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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