ā 53 ā
Block distinction
Check
Block
code
Indoor P.C.
board etc.
Not
displayed
Connecting
cable and
serial signal
Check
Cause of operation
code
Short-circuit or discon-
nection of the room
temperature sensor
(TA sensor).
Being out of place,
disconnection, short-
circuit, or migration of
heat exchanger sensor
(TC sensor)
Lock of indoor fan or
trouble on the indoor fan
circuit
Trouble on other indoor
P.C. boards
Return serial signal is not
sent to indoor side from
operation started.
(1) Defective wiring of
connecting cable
(2) Operation of compres-
sor thermo.
Gas shortage
Gas leak
Operation command
signal is not sent to
outdoor side.
Operation of diagnosis function
Judgment and action
1. Check the room temp. sensor.
2. When the room temp. sensor is
normal, check P.C. board.
1. Check heat exchanger sensor.
2. When heat exchanger sensor is
normal, check P.C. board.
1. Check P.C. board.
2. When P.C. board is normal, check
the motor.
Replace P.C. board.
1. When the outdoor unit never
operate:
(1) Check connecting cable, and
correct if defective wiring.
(2) Check 25A fuse of inverter P.C.
board.
(3) Check 3,15A of inverter P.C.
board.
2. To display [Other] block during
operation, check compressor
thermo. operation and supply gas
(check gas leak also).
3. Unit operates normally during
check.
If Return serial signal does not
stop between indoor terminal
board 2 and 3, replace inverter
P.C. board.
If signal stops between indoor
terminal board 2 and 3, replace
indoor P.C. board.
If Operation command signal does
not stop between indoor terminal
board 2 and 3, replace inverter P.C.
Air
conditioner
status
Operation
continues.
Operation
continues.
All off
Operation
continues.
Operation
continues.
Operation
continues.
Remarks
Displayed when
error is detected.
Displayed when
error is detected.
Displayed when
error is detected.
Displayed when
error is detected.
Flashes when
trouble is detected
on Return serial
signal, and normal
status when signal
is reset.
Flashes when
trouble is detected
on Operation
command signal,
and normal status
when signal is
reset.
10-4-3. Caution at Servicing
(1) After servicing, push the START/STOP button to return to the normal mode.
(2) After servicing by the check code, turn off breaker of the power supply, and turn on breaker of the power
supply again so that memory in the microcomputer returns the initial status. However, the check codes are
not deleted even if the power supply is turned off because they are stored in the fixed memory.
(3) After servicing, reset the check code by sending [ ] to the indoor unit in the service mode.
Then, the non-volatile memory is reset.
Table 10-4-1