─ 38 ─
Error code
(Controller
display)
LED1
(green)
Error
Cause
Corrective action
5101
4
blinks
Outdoor air
(OA) thermistor
related error
Faulty connection of the thermistor
(OA) connector
Check connection of the relay con-
nector and the connector (CN22)
on the control circuit board.
Thermistor (OA) failure
Disconnect the connector (CN22)
on the control circuit board,
and check the resistance of the
thermistor.
If the equivalent thermistor resis-
tance differs greatly from the
ambient temperatures, replace the
thermistor.
(Refer to “[4] Diagnosis of the
thermistor (page 46)” in “Failure
mode 7”.)
5102
5
blinks
Return air (RA)
thermistor
related error
Faulty connection of the thermistor
(RA) connector
Check connection of the relay con-
nector and the connector (CN5) on
the control circuit board.
Thermistor (RA) failure
Disconnect the connector (CN5)
on the control circuit board,
and check the resistance of the
thermistor.
If the equivalent thermistor resis-
tance differs greatly from the
ambient temperatures, replace the
thermistor.
(Refer to “[4] Diagnosis of the
thermistor (page 46)” in “Failure
mode 7”.)
6201
-
Controller circuit
board failure
Controller failure
Replace the controller.
6202
-
Controller circuit
board failure
Controller clock does not function
correctly.
Replace the controller.
6831
9
blinks
Controller com-
munication error
(no signal)
The controller is connected to the
incorrect terminal block (TB5 [A] [B]).
Connect the controller cable to the
terminal block (TM4 [1] [2]).
Faulty connection of the controller
cable
Refer to section [2] of “Failure
mode 1”.
If the error code does not disap-
pear, investigate noise on the con-
troller cable.
If the problem persists, replace the
control circuit board or controller.
6832
9
blinks
Controller com-
munication error
(synchronization
recovery error)
Faulty connection of the controller
cable
Refer to section [2] of “Failure
mode 1”.
If the error code does not disap-
pear, investigate noise on the con-
troller cable.
If the problem persists, replace the
control circuit board or controller.