Panasonic U-4LE2E5 Service Manual & Test Run Service Manual page 139

3. Mini VRF Alarm Codes
F17 Alarm
Alarm code F17
Alarm meaning Low pressure sensor has failure. (LPS)
Alarm conditions (1) Sensor short circuit
(2) Sensor open circuit
Probable cause (1) Sensor malfunction (including connector)
(2) The Outdoor Unit Control PCB malfunction
Check (1) Measure the sensor resistance. Check that the sensor is operating normally.
(2) Use a remote monitor or a PC monitor to check the temperature that is recognized by the
microcomputer.
Correction —
Example —
Notes —
F31 Alarm
Alarm code F31
Alarm meaning EEPROM on outdoor unit PCB has failure.
Alarm conditions (1) Non-volatile memory is not present when power initialization occurs.
(2) Read values do not match after writing to non-volatile memory is complete.
Probable cause (1) Memory was not inserted after the Outdoor Unit Control PCB was replaced.
(2) The lifetime of the non-volatile memory has been reached.
(3) Non-volatile memory is installed incorrectly (wrong direction, bent pins, etc.).
Check (1) Check the non-volatile memory on the Outdoor Unit Control PCB.
Correction —
Example —
Notes —
H01 Alarm (U-4LE2E5, U-5LE2E5, U-6LE2E5)
Alarm code H01
Alarm meaning Compressor primary current is overcurrent.
Alarm conditions Compressor (INV) primary current detected overcurrent higher than 32.2 (A).
Probable cause (1) Wiring failure
(2) Power supply voltage malfunction (sudden-voltage-drop)
(3) The Outdoor Unit Control PCB or the HIC PCB failure.
Check (1) Wiring failure
Forgot to connect the wires L, N. Check whether the terminals are connected correctly.
(2) Check the power supply voltage.
Correction (1) Wiring failure
Correct the disconnection and wiring failure.
(2) Correct the power supply voltage.
(3) Replace the Outdoor Unit Control PCB or the HIC PCB.
Example —
Notes —
H01 Alarm (U-4LE2E8, U-5LE2E8, U-6LE2E8)
Alarm code H01
Alarm meaning Compressor primary current is overcurrent.
Alarm conditions Compressor (INV) primary current detected overcurrent higher than 14.0 (A).
Probable cause (1) Wiring failure
(2) Power supply voltage malfunction (sudden-voltage-drop)
(3) The Outdoor Unit Control PCB or the HIC PCB failure.
Check (1) Wiring failure
Forgot to connect the wires L1, L2, L3. Check whether the terminals are connected correctly.
(2) Check the power supply voltage.
Correction (1) Wiring failure
Correct the disconnection and wiring failure.
(2) Correct the power supply voltage.
(3) Replace the Outdoor Unit Control PCB or the HIC PCB.
Example —
Notes —
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Mini VRF SYSTEM
Trouble Diagnosis
6