Normal - Daikin VRV IV+ Service Manual

2 | Troubleshooting
2.4.20 Symptom: Unit operation problems
Symptom
Unit(s) do not operate
Operation sometimes
stops
Service manual
202
Possible failure
Unit(s) do not operate
All indoor units show
icon blinking continuously
Indoor unit(s) show
icon blinking temporarily
when ON button is pressed
Indoor units show fan-only
mode
Power failure
Root cause
Missing or abnormal power
supply (reverse phase,
missing phase, abnormal
voltage...) to the outdoor
unit
Indoor unit(s) do not
receive power supply
Mismatch of combination
of outdoor unit and indoor
unit
Out of operation range
No Cool/Heat master is set Select Cool/Heat Master by
The unit(s) are either
under Centralized Control
and prohibited to operate
or under Forced OFF
operation by T1/T2 input
Transmission initialization
not completed
A power failure
consecutively more than 2
cycles may stop the air
conditioner operation
Repair
Check Power Supply. See
"4.1 Electrical
4
circuit" [ 356]
Check power supply to the
indoor unit(s), check if HAP
Led blinks, check fuse(s) on
indoor unit board. Also
check BPMKs in case
indoor unit is of RA type.
Check error codes. Check
compatibility
Check operation range on
databook
pressing Operating Mode
button on the desired unit.
The symbol will fade-away
for Cool/Heat Master and
will be fixed (not blinking)
for the remaining indoor
units
Release prohibitions from
central controller or check
T1/T2 contact status or
check indoor unit field
setting for forced off
See "To check F1-F2
4
transmission" [ 358].
Perform transmission re-
initialization
Check transmission wiring
Check indoor unit PCBs
Check outdoor unit main
PCB, see "3.11 Main
4
PCB" [ 290]
Restore power supply. See
"4.1 Electrical
4
circuit" [ 356]
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05