MCAC-VTSM-2015-10
R410A All DC Inverter V5 X Series 50Hz
Troubleshooting 139
4.3 E2: Communication error between indoor units and the master unit
The error will only display on faulty slave unit, all the ODUs will be on standby.
E2: Indoor units and outdoor unit
communication error
Communication wires P, Q, E are
short circuited or disconnected
(Measure the resistance among P Q
and E, the normal resistance between
P and Q is
120Ω, P and E is infinite, Q
and E is infinite.)
Reconnect the communication wires
Communication wires are not
connected in series
Interference from high voltage lines
(voltage over 220V is high voltage
power)
Communication wires are close to an
electromagnetic interference source.
Such as transformer, strong
fluorescent lamp, etc.
Remove the interference source, or use
device to shield the communication wire
The length of communication wire is
over 1200m
Reduce the wire length to less than
1200m or strengthen the signal
Connect the communication wires in
series
Ensure the communication wires and
high voltage lines are separated
Outdoor main PCB is damaged
Replace the outdoor main PCB
No
No
No
No
Yes
Yes
Yes
Yes
Yes
No