R410A Full DC Inverter Split Duct Type Technical Manual MCAC-UTSM-201503
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E2: Indoor & outdoor unit communication error
E2: Indoor units and outdoor
unit communication error
Communication wires P, Q, E are
short circuit or disconnected (Measure
the resistance among P Q and E, the
normal resistance is
120Ω)
Reconnect the communication
wires
Communication wires are not
connected in line shape
The communication wires are interfered
by high voltage power (voltage over
220V is high voltage power)
Communication wires are close to
electromagnetic interference source.
Such as transfer, strong fluorescent
lamp, etc.
Remove the interference source, or
use device to filter out the interference
The length of communication wire is
over 1200m
Adjust the wire length to less than
1200m or strengthen the signal
Yes
Yes
Yes
Connect the communication wires
in line shape
No
No
No
No
No
Yes
Ensure the communication wires and
high voltage wires do not twining
Yes
Outdoor main control
board is damaged
Replace the outdoor
main control board