What It Means
Malfunction of leaving water temperature thermistor or drain pipe heater.
Daikin Chiller
Daikin Chiller Error Code 81
Troubleshooting guide for the Daikin Chiller system fault 81.
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Possible Causes
- Defective connector contact.
- Defective leaving water temperature 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 leaving water temperature thermistor or drain pipe heater
All Recorded Causes
Defective connector contact Defective leaving water temperature thermistor
Verify Before Replacing Parts
- Confirm the exact Daikin model family and chiller context before acting on a generic code description.
- Verify the sensor or thermistor reading against the expected range for the current operating condition, keeping in mind that defective connector contact.
- Check the sensor harness and board connection before condemning the sensor itself; on Daikin units this is also where you'd confirm defective leaving water temperature thermistor.
- After the correction, run the system long enough to confirm the chiller fault does not return under normal load.
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