Daikin RX-W Series, Service Manual

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Troubleshooting for FDMQ, FFQ Series SiUS092230EA
140 Part 6 Service Diagnosis
6.2 Drain 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, X25A on indoor unit PCB
Troubleshooting
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).
(R25079)
NO
YES
NO
NO
YES
YES
Is the drain
pump connected to X25A on
the indoor unit
PCB?
NO
Is the drain water level
abnormally high?
YES
YES
Is the float switch
connected to X15A?
NO
Does the drain
pump work after the power
supply is on?
Is the voltage of
connector X25A 13 VDC?
YES
Remove the float switch from
X15A, short circuit X15A, and
restart operation.
NO
Does
A3
appear on the remote
controller display?