Panasonic U-4LE2E5 Service Manual & Test Run Service Manual page 149

Check Check the valve, mechanical valve and outdoor fan.
3. Mini VRF Alarm Codes
Correction —
Example —
—
Notes
P22 Alarm
Alarm code P22
Alarm meaning Outdoor unit fan motor has failure.
Alarm conditions Fan motor start failure, fan motor Hall IC input failure
Probable cause (1) Wiring failure
(2) Outdoor Unit Control PCB failure
(3) Fan failure
(4) Fan motor failure
Check (1) Wiring check
1-1 Are the connctors "CN-FM" firmly connected to the Outdoor Unit Control PCB
(2) Outdoor fan motor check
2-1 Disconnect the connectors "CN-FM" from the Outdoor Unit Control PCB and rotate the
(3) Outdoor control PC board check
3-1 Turn the power on and run the unit again; is P22 triggered again? Or can you see or
3-2 Replace the Outdoor Unit Control PCB.
3-3 If there is nothing particularly out of the ordinary, see what happens.
Correction (1) Correct the wiring.
(2) Remove the obstacles attached to the fan.
(3) Replace the fan motor.
(4) Replace the Outdoor Unit Control PCB.
Example —
Notes Turn OFF the power, and check the continuity of "+" and "–" on the Outdoor Unit Control PCB.
P29 Alarm
Alarm code P29
Alarm meaning Compressor start failure. Compressor is missing phase or reverse phase.
Alarm conditions This alarm may occur at start, and occurs when open phase or lock alarm is detected or the
compressor is in reversed-phase, and when a DCCT failure occurs.
Probable cause (1) Power supply voltage malfunction
(2) Wiring failure (missing, connection failure, miswiring, reversed-phase)
* Wiring between the HIC PCB and compressor
Check (1) Check the power supply and voltage.
Check whether the voltage between each of the phases is correct while the compressor is
running.
(It is necessary to check the compressor while running because the voltage may decrease
when the compressor starts running.)
(2) Check the wiring.
Check whether the following wiring is missing, connection failure or miswiring (position of U, V,
W is properly placed).
• Wiring between the HIC PCB and compressor
• HIC PCB side
• Compressor side
Correction (1) Correct the power supply voltage.
(2) Correct the wiring.
(3) Replace the HIC PCB.
(4) Replace the compressor.
Example —
(lock engaged)?
If "Yes", see "2-1".
If "No", correct the connector connections.
outdoor fan by hand ; does it rotate freely?
(Check the outdoor fan motor lock)
If "Yes", see "3-1".
If "No", replace the outdoor fan motor.
hear anything that is obviously wrong in its rotation?
If "Yes", see "3-2".
If "No", see "3-3".
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Mini VRF SYSTEM
Trouble Diagnosis
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