Service manual

57
9.2.2 Indoor unit and outdoor unit communication protection error diagnosis and solution
Yes
No
No
Change the indoor PCB
Change the outdoor PCB
Power on. Is the E1 extinguished
after 3 minutes?
Yes
Power on. Is the E1 extinguished
after 3 minutes?
Change the outdoor PCB
Yes
Power off, then power on the A/C by
the breaker.(reconnect the power
wire). Is the E1 extinguished?
Check the wiring on the outdoor
terminal and indoor terminal follow
the wiring diagram. Is all the
connecting correctly?
-24V<Vs<+24V?
(Vs is the voltage between S and N).
No
Is the wiring to the outdoor PCB
connecting correctly?
Is the wiring to the indoor PCB
connecting correctly?
No
Change the indoor PCB
Yes