Panasonic U-4LE2E5 Service Manual & Test Run Service Manual page 135

3. Mini VRF Alarm Codes
E16 Alarm
Alarm code E16
Alarm meaning More indoor units are found in Auto Addressing than the setting on outdoor PCB.
Alarm conditions • The number of indoor units was too many when auto address setting was performed.
• After initial communications were completed, an unrecognized unit was detected.
Probable cause (1) The number of indoor units set at the indoor unit quantity setting SW (SW3, SW4) on the
Outdoor Unit Control PCB is less than the number set.
(2) The inter-unit control wiring is wired incorrectly.
Check (1) See the section "7. TEST RUN" and check the number of indoor units that is set.
(2) Check the inter-unit control wiring at the indoor and outdoor units.
Correction After correcting the indoor unit quantity setting or the inter-unit control wiring, perform auto
address setting again.
Example —
Notes —
E20 Alarm
Alarm code E20
Alarm meaning No indoor unit responded in Auto Addressing.
Alarm conditions When auto address setting was performed, no indoor units were recognized.
Probable cause (1) The inter-unit control wiring from the outdoor unit to the indoor units has been cut.
(2) Serial wire is disconnected at the outdoor unit.
(3) The power is OFF at all indoor units in the system.
Check (1) Check whether the inter-unit control wiring from the outdoor unit to the indoor units is cut.
(2) Check whether serial wire is disconnected at the terminal base.
(3) Check the power at the indoor units.
Correction (1) Reconnect the inter-unit control wire from the outdoor unit to the indoor unit.
Example —
Notes Position of serial terminal base
U-4LE2E5, U-5LE2E5, U-6LE2E5 U-4LE2E8, U-5LE2E8, U-6LE2E8
terminal base
6 - 7
Mini VRF SYSTEM
Trouble Diagnosis
terminal base
6