Daikin Chiller

Daikin Chiller Error Code 84

Troubleshooting guide for the Daikin Chiller system fault 84.

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What It Means

System No.

Possible Causes

  • Defective connector contact.
  • Defective heat exchanger 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

System No. 1 Malfunction of heat exchanger thermistor

All Recorded Causes

Defective connector contact Defective heat exchanger thermistor

Verify Before Replacing Parts

  1. Confirm the exact Daikin model family and chiller context before acting on a generic code description.
  2. Verify the sensor or thermistor reading against the expected range for the current operating condition, keeping in mind that defective connector contact.
  3. Check the sensor harness and board connection before condemning the sensor itself; on Daikin units this is also where you'd confirm defective heat exchanger 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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