187 to 253 V AC?
12 to 16 V DC?
187 to 253 V AC?
12 to 16 V DC?
NO
YES
NO
YES
NO
YES
YES
NO
YES
NO
Check the voltage between S1
and S2 on the terminal block
(TB4) of the indoor unit.
Check the voltage among L1 and L2
on the terminal block (TB1) of the
outdoor power circuit board.
Check the voltage of indoor
controller board (CN2D).
Check the voltage of the unit after
removing the indoor power board
(CN2S).
Check the voltage between S1
and S2 on the terminal block
(TB1) of the outdoor unit which
is used to connect the indoor
unit and the outdoor unit.
Troubles concerning
power supply
&KHFNWKHSRZHUZLULQJ
to the outdoor unit.
&KHFNWKHEUHDNHU
%DGZLULQJRIWKH
outdoor controller
board
7KHIXVHVRQWKH
outdoor
controller circuit
board are blown.
&KHFNWKHZLULQJRIWKH
outdoor unit.
&KHFNLIWKHZLULQJLVEDG
Check if the fuses are blown.
The fuses on the outdoor
controller circuit board will
be blown when the indoor
/outdoor connecting wire
short-circuits.
%DGZLULQJRIWKH
outdoor controller
board
7KHIXVHVRQWKH
outdoor
controller circuit
board are blown.
&KHFNLIPLVZLULQJEUHDNLQJ
or poor contact is causing this
problem. Indoor/outdoor
connecting wire is polarized
3-core type. Connect the
indoor unit and the outdoor
unit by wiring each pair of
66DQG6RQWKHERWK
side of indoor/outdoor
terminal blocks.
'HIHFWLYHLQGRRU
power board
5HSODFHWKHLQGRRU
power board.
'HIHFWLYHLQGRRU
controller board
5HSODFHWKHLQGRRU
controller board.
0LVZLULQJEUHDNLQJ
or poor connection of
indoor/outdoor
connecting wire
Check if there is miswiring
or breaking of wire.
Symptoms: Nothing is displayed on the remote controller
1
Diagnosis flow
Cause
Inspection method and
troubleshooting
LED display of the indoor
controller board
LED1 :
LED2 :
LED3 :
187 to 253 V AC?
OCH567