E25 Alarm; E26 Alarm; E29 Alarm; E31 Alarm - Panasonic U-8ME1E81 Service Manual

4. 2WAY 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
1
Correction
Example
Notes
2

E29 Alarm

Alarm code
Alarm meaning
Alarm conditions
3
Probable cause
Check
4
Correction
Example
Notes
5

E31 Alarm

Alarm code
Alarm meaning
Alarm conditions
6
Probable cause
Check
7
Correction
Example
Notes
8
E25
Outdoor unit address setting failure (duplication)
Communication by outdoor unit main-sub 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 outdoor unit main-sub control wiring for 3 minutes or longer.
(1) The outdoor unit quantity is set incorrectly.
(2) The outdoor unit main-sub control wiring is cut.
(1) Check the outdoor unit quantity setting again.
(2) Check the outdoor unit main-sub control wiring.
(1) Correct the incorrect outdoor unit quantity setting.
(2) Repair the outdoor unit main-sub control wiring.
—
Recovery from this alarm occurs automatically (when the set outdoor unit quantity matches the
number of outdoor units detected on the outdoor unit main-sub 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 outdoor unit main-sub 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 outdoor unit main-sub control wiring.
(2) Check the RC connectors.
(3) Check the power at the outdoor unit (main).
(1) Repair the outdoor unit main-sub 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.
—
—
3-12
2WAY SYSTEM
Trouble Diagnosis