What It Means
Malfunction of liquid pipe thermistor for heat exchanger.
Daikin Packaged Unit
Daikin Packaged Unit Error Code C4
Troubleshooting guide for the Daikin Packaged Unit system fault C4.
Possible Causes
- Defective thermistor for liquid pipe.
- Defective indoor unit PCB.
- Defective connector contact.
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 liquid pipe thermistor for heat exchanger
All Recorded Causes
Defective thermistor for liquid pipe Defective indoor unit PCB Defective connector contact
Verify Before Replacing Parts
- Confirm the exact Daikin model family and packaged 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 thermistor for liquid pipe.
- Check the sensor harness and board connection before condemning the sensor itself; on Daikin units this is also where you'd confirm defective indoor unit PCB.
- After the correction, run the system long enough to confirm the packaged fault does not return under normal load.
Still unsure about this fault?
ACLogics walks you through Daikin Packaged Unit diagnostics step-by-step — so you confirm the cause before swapping parts.
