Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 914

FDC-HKX
Error display : No display
1
LCD display : No display
Indoor unit
Red LED Stays OFF
Green LED Lights continuously
● When the LCD display (Center/Remote, temperature display, etc.) of remote controller flashes, it means the polarity on the
unit is not yet determined. Polarity determination is completed within a few seconds after the power on. If it is not completed
in time, CPU out of cotnrol, etc. is suspected.
Indoor unit PCB green LED:
1 unit only
on network
Defective indoor unit PCB
Replacement
912
[Polarity determination trouble]
Outdoor unit
Red LED
Green LED Lights continuously
Keeps flashing?
YES
Power supply reset
NO
Is it more than
10 sec.
after power on?
YES
Is the remote
YES
controller LCD
nomal
(1)
NO(Center or Remote only display)
(3)
Defective indoor unit PCB on
some units
Stays OFF
Notes (1) When CPU of one unit goes out of control, it
occuping the transmission section of the network,
so the transmission of other units are not done and
the polarity of the whole network will not be de-
termined.
(2) The unit which has its indoor and green LED light-
ing continuously (or no lighting) is the one with a
defective indoor unit PCB.
(3) If it becomes normal after replacing the PCB. it
can be considered that the PCB. is defective (de-
fective network transmission circuit).
If yes, it is a
malfunction by
electrical noise
Multiple units
on network
(2) (3)
Replacement