Panasonic U-36LE1U6 Service Manual page 38

4. Mini VRF Alarm Codes 4. Mini VRF Alarm Codes
P16 alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
P22 alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
P26 alarm
Alarm code
3
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
P29 alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
P16
Inverter compressor overcurrent alarm
This alarm occurs when current trouble or current detection trouble occurs at an inverter frequency
of less than 80 Hz after start (when trouble judgment current is detected in the primary or
secondary current, or when an instantaneous secondary current of 48 A or higher is detected).
There is a strong possibility of a compressor failure.
An alarm occurs for current detection trouble when it is judged that no current is flowing after start
(DCCT is damaged). In this case, the cause is a DCCT failure.
Check the power wiring and connector wiring.
It is possible to resolve this trouble by limiting the maximum frequency.
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P22
Fan motor trouble
Fan motor start failure, fan motor Hybrid IC input failure
Possible causes are a Hybrid IC input circuit failure or a fan HIC failure.
Check the fan motor wiring, the Hybrid IC wiring, and the connector connections. If the wiring and
connectors are normal, then check that the capacitor of the Hybrid IC input circuit is securely
soldered onto the PCB. Also use a tester and measure the resistance between fan HIC power
(HIC+) and ground (HIC–). If there is a short circuit, there is an HIC malfunction.
If the fan does not start, the below corrections may be effective.
(1) If there is a fan HIC failure or circuit failure, replace the PCB.
(2) If the fan motor is locked, replace the fan motor.
—
Turn OFF the power, and check the conductivity of "+" and "–" on the main PCB.
P26
Inverter compressor high-frequency overcurrent alarm
This alarm occurs when current trouble or current detection trouble occurs at an inverter frequency
of 80 Hz or higher after start (when trouble judgment current is detected in the primary or
secondary current, or when an instantaneous secondary current of 48 A or higher is detected).
The detection methods are the same as for P16. However the fact that operation up to high
frequencies is possible does not necessarily mean that a compressor failure is the cause of the
trouble. Start the compressor several times. If alarm P26 occurs every time and alarm P16 does
not occur at all, then the possibility of a compressor failure is low.
Check the power wiring and connector wiring.
It is possible to resolve this trouble by limiting the maximum frequency.
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—
P29
Inverter compressor missing phase or lock alarm
This alarm may occur at start, and occurs when missing phase or lock is detected, and when a
DCCT failure occurs.
Generally this alarm occurs when the refrigerant pressure balance is uneven at start, when
inverter compressor lock occurs, there is a missing phase in the inverter compressor wiring, or a
DCCT failure occurs. This can be judged to be starting trouble which is not caused by HIC.
Check the power wiring and connector wiring.
DCCT failure (replace PCB) or compressor failure
—
Use a tester to measure the voltage between the DCCT output terminal on the rear of the PCB
and the ground. If the voltage is not within 2 – 3 V, then the DCCT has malfunctioned.
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Trouble Diagnosis Trouble Diagnosis