What It Means
Malfunction of freezing protection.
Daikin Chiller
Daikin Chiller Error Code A4
Troubleshooting guide for the Daikin Chiller system fault A4.
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Possible Causes
- Shortage of water volume.
- Low water temperature setting.
- Defective 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 freezing protection
All Recorded Causes
Shortage of water volume Low water temperature setting Defective 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 shortage of water volume.
- Check the sensor harness and board connection before condemning the sensor itself; on Daikin units this is also where you'd confirm low water temperature setting.
- After the correction, run the system long enough to confirm the chiller fault does not return under normal load.
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