Panasonic CU-8ME1XPK - Malfunction of Transmission between Outdoor Units

Troubleshooting PACD011001C2
526 Troubleshooting UM Combination “MA1R Series” Using R-407C
3.29 Malfunction of Transmission Between Outdoor Units
Remote Controller
Display
U7
Supposed Causes
„
Improper connection of transmission wiring between outdoor unit and BMS interface adaptor for
outdoor unit
„
Improper cool/heat selection
„
Improper cool/heat unified address (outdoor unit, BMS interface adaptor for outdoor unit)
„
Defect of outdoor unit PC board (A1P)
„
Defect of BMS interface adaptor for outdoor unit
Troubleshooting
(VF056)
NO
YES
Fix the indoor/outdoor unit
transmission wiring.
Replace the outdoor unit PC
Board (A1P).
YES
NO
C/H SELECT is set to "IND".
Cool / heat selection is unified.
C/H SELECT
is set to "MASTER."
NO
Is the indoor
/ outdoor unit transmission
wiring normal?
C/H SELECT
is set to "SLAVE."
YES
NO
Check
and see if the following items
are normal.
NO
Does
a malfunction occur when
the cool / heat selector is set
to "IND?"
YES
Set C/H SELECT to "IND."
The cool / heat unified address for
outdoor units in outdoor - outdoor
unit transmission is duplicated.
Set the address correctly.
YES
NO
NO
YES
YES
Replace BMS interface adaptor
for outdoor unit.
Replace the outdoor unit PC
board (A1P).
BMS interface adaptor for outdoor unit
•Is there continuity?
•Does the cool/heat unified address match?
Outdoor unit (unified master unit)
•Is there continuity?
•Does the cool/heat unified address match?
Fix the problem.
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.