SiSG121917E
Troubleshooting for MSP Duct Type Indoor Unit
Part 6 Service Diagnosis
128
Notes
6.2 Drain Water Level Control System Abnormality
Error Code
A3
Method of Error
Detection
The float switch detects error.
Error Decision
Conditions
When the water level reaches its upper limit and when the float switch turns OFF
Supposed
Causes
Defective drain pump
Improper drain piping work
Clogged drain piping
Defective float switch
Defective indoor unit PCB
Defective short circuit connector X15A on indoor unit PCB
Troubleshooting
Switch: DS1 on control PCB
For the location of the DIP switch, refer to page 34.
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Connect the drain pump.
Replace the indoor unit
PCB (control PCB).
Replace the drain pump.
There is a drain system
abnormality.
Connect the float switch.
Replace the float switch.
Replace the indoor unit
PCB (control PCB).
(R22268)
NO
YES
NO
NO
YES
YES
Is the drain
pump connected to the
indoor unit PCB?
NO
Is the drain water level
abnormally high?
YES
YES
Is the float switch
connected to X15A?
NO
YES
Remove the float switch from
X15A, short circuit X15A, and
restart operation.
NO
Does
A3
appear on the remote
controller display?
Does the
drain pump work after
restarting operation?
Set the
switch
#
on
the indoor unit PCB to
emergency (EMG) and check the
voltage of X25A. 220 ~
240 VAC?
