Sharp AE-X3M18JR Service Manual page 23

2. When one room is not cooled (other rooms are cooled)
Is the timer lamp of the
indoor unit in the room
not cooled flashing ?
No
Press the OPERATION
button to start operating
the air-conditioner.
(Set the cooling mode
to 18ºC.)
Is the timer lamp of the
indoor unit in the room
not cooled flashing ?
No
Check that the power
No between the terminal
board "N" and "1" of the
indoor unit is AC 230V.
Yes
Replace the indoor
control PWB.
Repair the wiring
between the units.
3. When all rooms are not heated
Does the air get cooler in the cooling operation mode?
Refer to 1 All rooms are not cooled.
Yes
The heating cycle is normal.
Pressure check
Yes
Check the failure
symptom with the failure
Yes
diagnosis mode.
Short circuit of the thermistor error
Open circuit of the thermistor error
Is the resistance value of the ther-
mistor for UNIT A (TH6), UNIT B
(TH7) or UNIT C (TH8)
No
Replace the thermistor.
Replace the outdoor control PWB
or the expansion valve (UNIT A)
or the expansion valve (UNIT B)
or the expansion valve (UNIT C)
No
Check the four-way valve. Has the cycle been switched?
Is AC230V applied between the connector
(CN4) 1 and 3 of the 4-way valve ?
Replace the outdoor control P.W.B..
Abnormal fan motor of
indoor unit
Is the resistance value of the
Yes
winding in the fan motor ?
Replace the indoor fan motor.
Yes
Press the ON switch on the remote control to run the air conditioner.
Set the temperature to 32ºC in the heating mode and start operation.
Is the outdoor compressor running?
No
No
Replace the 4-way valve.
3 – 8
Open circuit of serial signal line
Short circuit of serial signal line
Is the wiring between the
No
units connected by mistake
or broken ?
Yes
Yes
Replace the indoor control PWB.
No
Yes
No
A
To
Yes
No
Repair the wiring between
the units.