Panasonic U-8MF2E8 Service Manual page 132

4. 3WAY Alarm Codes
E25 Alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
E26 Alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
E29 Alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
5
Correction
Example
Notes
E31 Alarm
Alarm code
Alarm meaning
Alarm conditions
Probable cause
Check
Correction
Example
Notes
E25
Outdoor unit address setting failure (duplication)
Communication by inter-outdoor unit control wiring was received that contained the same
address as that unit 5 times or more within 3 minutes.
The unit number is set incorrectly.
Check the unit number again.
Correct the incorrect unit number setting.
—
Recovery from this alarm occurs automatically (when communication that contains the same
address is not received for 3 minutes).
E26
Mismatch in outdoor unit quantity
After power initialization, the set outdoor unit quantity did not match the number of outdoor units
detected on the inter-outdoor unit control wiring for 3 minutes or longer.
(1) The outdoor unit quantity is set incorrectly.
(2) The inter-outdoor unit control wiring is cut.
(1) Check the outdoor unit quantity setting again.
(2) Check the inter-outdoor unit control wiring.
(1) Correct the incorrect outdoor unit quantity setting.
(2) Repair the inter-outdoor unit control wiring.
—
Recovery from this alarm occurs automatically (when the set outdoor unit quantity matches the
number of outdoor units detected on the inter-outdoor unit control wiring).
E29
Outdoor unit failed to receive communication from outdoor unit (main).
Outdoor unit communications from outdoor unit (main) were interrupted for 3 minutes or longer.
(1) After initial communications were completed, the inter-outdoor unit control wiring was
cut.
(2) After initial communications were completed, the RC connector became disconnected.
(3) The power at the outdoor unit (main unit) is turned OFF.
(1) Check the inter-outdoor unit control wiring.
(2) Check the RC connectors.
(3) Check the power at the outdoor unit (main).
(1) Repair the inter-outdoor unit control wiring.
(2) Correct the RC connector connection.
(3) Turn ON the outdoor unit (main) power.
—
—
E31
Communication error between two microcomputers on the Control P.C. Board
—
When does it occur?
(1) When failed in rewriting microcomputer.
(2) When the unit power shut down during rewriting microcomputer.
(3) When wiring between PCB and ROM writer disconnected.
(1) Rewrite microcomputer again.
(2) Switch on the unit power again.
Replace Control PCB.
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3WAY SYSTEM
Trouble Diagnosis