Communication Malfunction E6; Communication Error Of Indoor And Outdoor Unit - Toyotomi KURO Mini Service Manual

2. Communication malfunction

2.1 Communication error of indoor and outdoor unit

Main check points:
(1) Connection wire between indoor unit and outdoor unit
(2) Wiring inside the unit
(3) Communication circuit of control board of indoor unit
(4) Communication circuit of control board of outdoor unit
Connect the connection wire of
indoor/outdoor unit correctly
according to the wiring diagram.
Eliminate
malfunction
Y
Note: method for checking the communication circuit of inverter split type and floor standing unit: cut off the
communication wires of indoor/outdoor unit, and then measure the voltage between COM and N of the control board
of outdoor unit (DC notch, about 56V)
Y
Check whether the connection
wire of controller inside the
electric box of indoor/outdoor
unit is loose.
Is the connection
Y
wire of electric box is
normal?
N
Check the communication
N
circuit of outdoor unit
Is there's problem
for the communication
circuit?
N
Replace the control board
of indoor unit.
Start
Check whether the
unit has operated normally before
the malfunction occurs.
Y
Replace the control
Y
board of outdoor unit.
Eliminate
malfunction
N
Y
End
N
Check the connection wire of
indoor unit and outdoor unit
according to the wiring diagram.
Is the
connection correct?
N
N
Connect the connection
wire of indoor/outdoor unit
correctly according to the
wiring diagram.
Eliminate
malfunction
Y